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1

Muir Inlet  

USGS Multimedia Gallery

Muir Glacier has retreated more than 2 km and ceased to have a tidewater terminus. Note that the retreat of Muir Glacier has left several ice-cored morainal mounds between the shoreline and the terminus. Since 1980, Muir Glacier has thinned by several hundred meters permitting a view of a mountain w...

2

Muir Inlet  

USGS Multimedia Gallery

This ship-deck-based photograph of Muir Glacier and Muir Inlet, Glacier Bay National Park and Preserve, St. Elias Mountains, Alaska, is taken towards the north-northwest and shows the nearly 50-m-high retreating tidewater terminus of the glacier with part of its face capped by a few angular sé...

3

Muir Glacier and Muir Inlet 1980  

USGS Multimedia Gallery

This ship-deck-based August 1980 photograph of Muir Glacier and Muir Inlet, Glacier Bay National Park and Preserve, St. Elias Mountains, Alaska, shows the nearly 200-ft-high retreating tidewater end of Muir Glacier with part of its face capped by a few angular pinnacles of ice, called séracs....

4

Muir Glacier and Muir Inlet 2003  

USGS Multimedia Gallery

This photo was taken in September 2003; in the 23 years between photographs, Muir Glacier has retreated more than a mile and ceased to have a tidewater terminus. Since 1980, Muir Glacier has thinned by more than 600 ft, permitting a view of a mountain with a summit elevation of greater than 4000 ft,...

5

John Muir Photographs  

NSDL National Science Digital Library

John Muir was a wanderer, a thinker, and a tinkerer of great repute. This digital collection from the University of the Pacific in Stockton, California brings together images of this great American for use by researchers, scholars, and anyone else with a penchant for Muir's life and times. The images come from their special collections, and they include items from the formal John Muir Papers collection and the James Eastman Shone Collection of Muiriana. There are 242 images in the collection, and visitors can look over them at their leisure, or perform their own detailed search. There's much to look at here, as the shots include Muir with Andrew Carnegie in Los Angeles, Muir at his home in Martinez, and a fair number of shots of Muir walking through the wilderness he loved so dearly.

6

Ant Colonies for the Traveling Salesman Problem  

Microsoft Academic Search

We describe an artificial ant colony capable of solving the traveling salesman problem (TSP).Ants of the artificial colony are able to generate successively shorter feasible tours by usinginformation accumulated in the form of a pheromone trail deposited on the edges of the TSPgraph. Computer simulations demonstrate that the artificial ant colony is capable of generatinggood solutions to both symmetric and

Luca Maria Gambardella; Marco Dorigo

1997-01-01

7

Ant colonies for the travelling salesman problem  

Microsoft Academic Search

We describe an artificial ant colony capable of solving the travelling salesman problem (TSP). Ants of the artificial colony are able to generate successively shorter feasible tours by using information accumulated in the form of a pheromone trail deposited on the edges of the TSP graph. Computer simulations demonstrate that the artificial ant colony is capable of generating good solutions

Marco Dorigo; Luca Maria Gambardella

1997-01-01

8

Ant Algorithms Solve Difficult Optimization Problems  

E-print Network

Ant Algorithms Solve Difficult Optimization Problems Marco Dorigo IRIDIA Universit´e Libre de Bruxelles 50 Avenue F. Roosevelt B-1050 Brussels, Belgium mdorigo@ulb.ac.be Abstract. The ant algorithms research field builds on the idea that the study of the behavior of ant colonies or other social insects

Libre de Bruxelles, Université

9

Solving the ANTS Problem with Asynchronous Finite State Machines  

E-print Network

Solving the ANTS Problem with Asynchronous Finite State Machines Yuval Emek, Tobias Langner, Jara + D) #12;Previous Work ANTS problem (Ants Nearby Treasure Search) introduced by Feinerman, Korman, Lotker, Sereni [PODC 2012] = #12;Previous Work ANTS problem (Ants Nearby Treasure Search) introduced

10

Solving the ANTS Problem with Asynchronous Finite State Machines  

E-print Network

Solving the ANTS Problem with Asynchronous Finite State Machines Yuval Emek1 , Tobias Langner2 the Ants Nearby Treasure Search (ANTS) problem introduced by Feinerman, Korman, Lotker, and Sereni (PODC-time of any ANTS algorithm. 1 Introduction "They operate without any central control. Their collective

11

Problems with ants The noted gourmet Pangolini Aardvark is preparing a late night snack of "Ant  

E-print Network

Problems with ants The noted gourmet Pangolini Aardvark is preparing a late night snack of "Ant au Chocolat" and "Ant au Fromage". This requires the use of a five foot pole. One end of the pole is over a bucket of melted chocolate and the other is over a bucket of melted cheese. Pangolini sprinkles some ants

Sadeh, Norman M.

12

Muir and Riggs Glaciers, Muir Inlet, Alaska - 1950  

USGS Multimedia Gallery

This, the first of two repeat photographs, documents significant changes that have occurred during the nine years between photographs A and B. Although Muir Glacier has retreated more than 3 kilometers and thinned more than 100 meters, exposing Muir Inlet, it remains connected with tributary Riggs G...

13

Muir and Riggs Glaciers, Muir Inlet, Alaska - 1941  

USGS Multimedia Gallery

This northeast-looking photograph, on the southeastern side of White Thunder Ridge ,shows the lower reaches of Muir Glacier, then a large tidewater calving valley glacier, and its tributary Riggs Glacier. The séracs in the lower right-hand corner of the photograph mark Muir Glacier’s te...

14

Solving Permutation Constraint Satisfaction Problems with Artificial Ants  

E-print Network

Solving Permutation Constraint Satisfaction Problems with Artificial Ants Christine Solnon 1 Abstract. We describe in this paper Ant­P­solver, a generic con­ straint solver based on the Ant Colony Optimization (ACO) meta­ heuristic. The ACO metaheuristic takes inspiration on the observa­ tion of real ants

Solnon, Christine

15

Muir-torre syndrome.  

PubMed

Muir-Torre syndrome (MTS) is a rare autosomal-dominant genodermatosis characterized by sebaceous neoplasms and one or more visceral malignancies. Sebaceous tumors include sebaceous adenoma and carcinoma, which may be solitary or multiple. Visceral malignancies most often arise in the colorectum and endometrium. Because a subset of patients with phenotypic MTS will have germline mutations in the DNA mismatch repair genes hMSH2 and hMLH1, MTS is considered a phenotypic subtype of Lynch syndrome (also known as hereditary nonpolyposis colorectal cancer syndrome), in which inherited defects in DNA mismatch repair genes result in microsatellite instability. Pathologists have an important role in the early detection and initial diagnosis of MTS: identification of at-risk individuals allows appropriate screening and surveillance for visceral malignancies, thereby reducing morbidity and mortality. Herein, we describe the clinicopathologic features of MTS. PMID:25427047

Bhaijee, Feriyl; Brown, Alexandra S

2014-12-01

16

Better Trained Ants for Genetic Programming W. B. Langdon and R. Poli  

E-print Network

Fe trail has been repeatedly used as a benchmark problem [ Jefferson et al., 1992, (John Muir trail Abstract The problem of programming an artificial ant to follow the Santa Fe trail has been repeatedly used) obliged to traverse the trail in approximately the correct order, (2) to find food quickly. We also

Fernandez, Thomas

17

Applying the Ant System to the Vehicle Routing Problem  

Microsoft Academic Search

In this paper we use a recently proposed metaheuristic, the Ant System, to solvethe Vehicle Routing Problem (VRP) in its basic form, i.e. with capacity anddistance restrictions, one central depot and identical vehicles. A "hybrid" Ant Systemalgorithm is first presented and then improved using problem specific information(savings, capacity utilization). Experiments on various aspects of the algorithm andcomputational results for fourteen

Bernd Bullnheimer; Richard F. Hartl; Christine Strauss

1997-01-01

18

Muir and Riggs Glaciers, Muir Inlet, Alaska - 2004  

USGS Multimedia Gallery

The second repeat photograph documents significant changes that have occurred during the 63 years between photographs A and C, and during the 54 years between photographs B and C. Muir Glacier has retreated out of the field of view and is now more than 7 kilometers northwest. Riggs Glacier has retre...

19

The John Muir Exhibit: Educational Resources  

NSDL National Science Digital Library

The John Muir Exhibit was created by the Sierra Club to display and commemorate the life of John Muir and his role in the environmental movement. The Educational Resources that are provided are for students and teachers from grade school to graduate school, interested in studying Muir's legacy as a naturalist, writer, conservationist and founder of the Sierra Club. A student page provides research materials from biographies to articles, and study guides assists teachers in preparing commemorations of Muir and his work, with focus on John Muir Day. A listing of John Muir awards provides students with the opportunity to apply for and win scholarships. Other John Muir Education programs are listed such as poster contests and case studies history projects.

20

An Improved Ant System Algorithm for the Vehicle Routing Problem  

Microsoft Academic Search

this paper an improved ant systemalgorithm for the Vehicle Routing Problem with one central depot and identical vehicles.Computational results on fourteen benchmark problems from the literatureare reported and a comparison with five other metaheuristic approaches to solvevehicle routing problems is made.

Bernd Bullnheimer; Richard F. Hartl; Christine Strauss

1997-01-01

21

Hybrid Ant Algorithm and Applications for Vehicle Routing Problem  

NASA Astrophysics Data System (ADS)

Ant colony optimization (ACO) is a metaheuristic method that inspired by the behavior of real ant colonies. ACO has been successfully applied to several combinatorial optimization problems, but it has some short-comings like its slow computing speed and local-convergence. For solving Vehicle Routing Problem, we proposed Hybrid Ant Algorithm (HAA) in order to improve both the performance of the algorithm and the quality of solutions. The proposed algorithm took the advantages of Nearest Neighbor (NN) heuristic and ACO for solving VRP, it also expanded the scope of solution space and improves the global ability of the algorithm through importing mutation operation, combining 2-opt heuristics and adjusting the configuration of parameters dynamically. Computational results indicate that the hybrid ant algorithm can get optimal resolution of VRP effectively.

Xiao, Zhang; Jiang-qing, Wang

22

The Ant System Applied to the Quadratic Assignment Problem  

Microsoft Academic Search

In recent years, there has been growing interest in algorithms inspired by the observation of natural phenomena to define computational procedures that can solve complex problems. We describe a distributed heuristic algorithm that was inspired by the observation of the behavior of ant colonies, and we propose its use for the quadratic assignment problem. The results obtained in solving several

Vittorio Maniezzo; Alberto Colorni

1999-01-01

23

Ants  

NSDL National Science Digital Library

In this outdoor activity, learners investigate ant behavior by testing ant feeding reactions to different types of food. Learners attempt to discover an ant "superfood" and use that food to try and get some ants from a colony to start a new one at a different location. Based on what learners observe, they also consider how ants communicate with each other.

Science, Lawrence H.

1980-01-01

24

Sebaceous neoplasia and Torre–Muir syndrome  

PubMed Central

Summary Sebaceous tumours include hyperplasia, adenoma, sebaceoma and carcinoma. Importantly, the latter three are potential markers of Torre–Muir syndrome; the hereditary association of sebaceous neoplasia and internal malignancy, most commonly colorectal carcinoma. The diagnostic features, differential diagnosis, molecular diagnostics and recent advances in pathogenesis of this rare group of tumours are discussed along with Torre–Muir syndrome and recommendations for screening for this important association. PMID:18670585

Lazar, A.J.F.; Lyle, S.; Calonje, E.

2007-01-01

25

MAX-MIN Ant System and local search for the traveling salesman problem  

Microsoft Academic Search

Ant System is a general purpose algorithm inspired by the study of the behavior of ant colonies. It is based on a cooperative search paradigm that is applicable to the solution of combinatorial optimization problems. We introduce MAX-MIN Ant System, an improved version of basic Ant System, and report our results for its application to symmetric and asymmetric instances of

Thomas Stutzle; Holger Hoos

1997-01-01

26

An Ant Colony System for the Open Vehicle Routing Problem  

Microsoft Academic Search

This paper studies the open vehicle routing problem (OVRP), in which the vehicles do not return to the starting depot after\\u000a serving the last customers or, if they do, they must make the same trip in the reverse order. We present an ant colony system\\u000a hybridized with local search for solving the OVRP (ACS-OVRP). Additionally, a Post-Optimization procedure is incorporated

Xiangyong Li; Peng Tian

2006-01-01

27

Ant colony optimization for solving university facility layout problem  

NASA Astrophysics Data System (ADS)

Quadratic Assignment Problems (QAP) is classified as the NP hard problem. It has been used to model a lot of problem in several areas such as operational research, combinatorial data analysis and also parallel and distributed computing, optimization problem such as graph portioning and Travel Salesman Problem (TSP). In the literature, researcher use exact algorithm, heuristics algorithm and metaheuristic approaches to solve QAP problem. QAP is largely applied in facility layout problem (FLP). In this paper we used QAP to model university facility layout problem. There are 8 facilities that need to be assigned to 8 locations. Hence we have modeled a QAP problem with n ? 10 and developed an Ant Colony Optimization (ACO) algorithm to solve the university facility layout problem. The objective is to assign n facilities to n locations such that the minimum product of flows and distances is obtained. Flow is the movement from one to another facility, whereas distance is the distance between one locations of a facility to other facilities locations. The objective of the QAP is to obtain minimum total walking (flow) of lecturers from one destination to another (distance).

Mohd Jani, Nurul Hafiza; Mohd Radzi, Nor Haizan; Ngadiman, Mohd Salihin

2013-04-01

28

Muir Glacier in Glacier Bay National Monument 1941  

USGS Multimedia Gallery

This August 1941 photograph is of Muir Glacier in Glacier Bay National Monument, Alaska. It shows the lower reaches of Muir Glacier, then a large, tidewater calving valley glacier and its tributary, Riggs Glacier. For nearly two centuries before 1941, Muir Glacier had been retreating. In places, a t...

29

Solving the Attribute Reduction Problem with Ant Colony Optimization  

NASA Astrophysics Data System (ADS)

Attribute reduction is an important process in rough set theory. More minimal attribute reductions are expected to help clients make decisions in some cases, though the minimal attribute reduction problem (MARP) is proved to be an NP-hard problem. In this paper, we propose a new heuristic approach for solving the MARP based on the ant colony optimization (ACO) metaheuristic. We first model the MARP as finding an assignment which minimizes the cost in a graph. Afterward, we introduce a preprocessing step that removes the redundant data in a discernibility matrix through the absorption operator and the cutting operator, the goal of which is to favor a smaller exploration of the search space at a lower cost. We then develop a new algorithm R-ACO for solving the MARP. Finally, the simulation results show that our approach can find more minimal attribute reductions more efficiently in most cases.

Yu, Hong; Wang, Guoyin; Lan, Fakuan

30

Ant colony system: a cooperative learning approach to the traveling salesman problem  

Microsoft Academic Search

This paper introduces ant colony system (ACS), a distributed algorithm that is applied to the traveling salesman problem (TSP). In ACS, a set of cooperating agents called ants cooperate to find good solutions to TSPs. Ants cooperate using an indirect form of communication mediated by pheromone they deposit on the edges of the TSP graph while building solutions. We study

Marco Dorigo; Luca Maria Gambardella

1997-01-01

31

Ant-Q: A Reinforcement Learning approach to the traveling salesman problem  

E-print Network

Ant-Q: A Reinforcement Learning approach to the traveling salesman problem Luca M. Gambardella@ulb.ac.be http://iridia.ulb.ac.be/dorigo/dorigo.html Abstract In this paper we introduce Ant-Q, a family to the solution of symmetric and asym- metric instances of the traveling salesman prob- lem (TSP). Ant

Gambardella, Luca Maria

32

An Improved Ant Colony Optimisation Algorithm for the 2D HP Protein Folding Problem  

E-print Network

An Improved Ant Colony Optimisation Algorithm for the 2D HP Protein Folding Problem Alena hydrophobic-polar (2D HP) protein folding problem. We present an improved version of our recently proposed Ant search. Overall, the results presented here establish our new ACO algorithm for 2D HP protein folding

Hoos, Holger H.

33

An Ant Colony Optimization Algorithm for the 2D HP Protein Folding Problem  

E-print Network

An Ant Colony Optimization Algorithm for the 2D HP Protein Folding Problem Alena Shmygelska, Rosal, the two dimensional hydrophobic-polar (2D HP) protein folding problem. We introduce an ant colony algorithm closely approaches that of specialised, state-of-the methods for 2D HP protein folding. 1

Hoos, Holger H.

34

Houston, We Have a Problem: Rasberry Crazy Ants  

E-print Network

Since first discovered in Pasadena in 2002 by pest control operator Tom Rasberry, Rasberry crazy ants have spread to 11 southeast Texas counties. Here are facts about these ants, with information for the public about what to do to avoid spreading...

Drees, Bastiaan M.

2009-03-15

35

Ant Colony System: A Cooperative Learning Approach to the Traveling Salesman Problem  

Microsoft Academic Search

This paper introduces ant colony system (ACS), a distributed algorithm that is appliedto the traveling salesman problem (TSP). In ACS, a set of cooperating agents calledants cooperate to find good solutions to TSPs. Ants cooperate using an indirect form ofcommunication mediated by pheromone they deposit on the edges of the TSP graphwhile building solutions. We study ACS by running experiments

Marco Dorigo

1996-01-01

36

A multiobjective ant colony-based optimization algorithm for the bin packing problem with load balancing  

Microsoft Academic Search

This paper presents ABLA, a novel multiobjective ant colony-based optimization algorithm to address the bin packing problem with load balancing. ABLA incorporates (1) a new probabilistic decision rule that builds solutions by making use of individual pheromone matrices for each objective function; (2) a new pheromone updating approach in which ants deposit variable amounts of pheromone; (3) two new local

Oscar D. Lara; Miguel A. Labrador

2010-01-01

37

MACS-VRPTW: A MULTIPLE ANT COLONY SYSTEM FOR VEHICLE ROUTING PROBLEMS WITH TIME WINDOWS  

Microsoft Academic Search

MACS-VRPTW, an Ant Colony Optimization based approach useful to solve vehicle routing problems with time windows is presented. MACS-VRPTW is organized with a hierarchy of artificial ant colonies designed to successively optimize a multiple objective function: the first colony minimizes the number of vehicles while the second colony minimizes the traveled distances. Cooperation between colonies is performed by exchanging information

Luca Maria Gambardella; E. Taillard; Giovanni Agazzi

1999-01-01

38

36 CFR 7.6 - Muir Woods National Monument.  

Code of Federal Regulations, 2010 CFR

...Property 1 2010-07-01 2010-07-01 false Muir Woods National Monument. 7.6 Section 7.6 Parks, Forests...REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.6 Muir Woods National Monument. (a) Fires. Fires are prohibited...

2010-07-01

39

36 CFR 7.6 - Muir Woods National Monument.  

...Property 1 2014-07-01 2014-07-01 false Muir Woods National Monument. 7.6 Section 7.6 Parks, Forests...REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.6 Muir Woods National Monument. (a) Fires. Fires are prohibited...

2014-07-01

40

36 CFR 7.6 - Muir Woods National Monument.  

Code of Federal Regulations, 2011 CFR

...Property 1 2011-07-01 2011-07-01 false Muir Woods National Monument. 7.6 Section 7.6 Parks, Forests...REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.6 Muir Woods National Monument. (a) Fires. Fires are prohibited...

2011-07-01

41

36 CFR 7.6 - Muir Woods National Monument.  

Code of Federal Regulations, 2012 CFR

...Property 1 2012-07-01 2012-07-01 false Muir Woods National Monument. 7.6 Section 7.6 Parks, Forests...REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.6 Muir Woods National Monument. (a) Fires. Fires are prohibited...

2012-07-01

42

36 CFR 7.6 - Muir Woods National Monument.  

Code of Federal Regulations, 2013 CFR

...Property 1 2013-07-01 2013-07-01 false Muir Woods National Monument. 7.6 Section 7.6 Parks, Forests...REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.6 Muir Woods National Monument. (a) Fires. Fires are prohibited...

2013-07-01

43

Solving a combinatorial problem using a local optimization in ant ...  

E-print Network

period of time, the shortest route will have high levels of pheromone so that all ants are .... to the temperature in simulated annealing, 0 ? q0 ? 1. If q ? q0 the .... Ph.D thesis, Dipartamento di Elettronica, Politecnico di Milano, Italy,. 1992, pp.

2005-12-24

44

Ants on a Doughnut Purpose. In this project you will use calculus to solve a geometry problem. This project  

E-print Network

Ants on a Doughnut Purpose. In this project you will use calculus to solve a geometry problem. This project serves as an introduction to differential geometry. The Problem. Two ants are exploring a doughnut and grease. The two regions are as far apart on the doughnut as they can be. The ants must leave a path

Brand, Neal

45

Study on MAX-MIN Ant System with Random Selection in Quadratic Assignment Problem  

NASA Astrophysics Data System (ADS)

Ant Colony Optimization (ACO), which is a type of swarm intelligence inspired by ants' foraging behavior, has been studied extensively and its effectiveness has been shown by many researchers. The previous studies have reported that MAX-MIN Ant System (MMAS) is one of effective ACO algorithms. The MMAS maintains the balance of intensification and diversification concerning pheromone by limiting the quantity of pheromone to the range of minimum and maximum values. In this paper, we propose MAX-MIN Ant System with Random Selection (MMASRS) for improving the search performance even further. The MMASRS is a new ACO algorithm that is MMAS into which random selection was newly introduced. The random selection is one of the edgechoosing methods by agents (ants). In our experimental evaluation using ten quadratic assignment problems, we have proved that the proposed MMASRS with the random selection is superior to the conventional MMAS without the random selection in the viewpoint of the search performance.

Iimura, Ichiro; Yoshida, Kenji; Ishibashi, Ken; Nakayama, Shigeru

46

An Ant Colony System Hybridized with a New Local Search for the Sequential Ordering Problem  

Microsoft Academic Search

We present a new local optimizer called SOP-3-exchange for the sequential ordering problem that extends a local search for the traveling salesman problem to handle multiple constraints directly without increasing computational complexity. An algorithm that combines the SOP-3-exchange with an Ant Colony Optimization algorithm is described and we present experimental evidence that the resulting algorithm is more effective than existing

Luca Maria Gambardella; Marco Dorigo

2000-01-01

47

An Elitist-Ant System for Solving the Post-Enrolment Course Timetabling Problem  

NASA Astrophysics Data System (ADS)

Ant System algorithms are nature-inspired population-based metaheuristics derived from the field of swarm intelligence. Seemingly, the ant system has a lack of search diversity control since it has only a global pheromone update that intensifies the search. Hence, one or more assistant mechanisms are required to strengthen the search of the ant system. Therefore, we propose, in this study, an elitist-ant system to strike a balance between search diversity and intensification while maintaining the quality of solutions. This process is achieved by employing two diversification and intensification mechanisms to assist both pheromone evaporation and elite pheromone updating, in order to gain a good control over the search exploration and exploitation. The diversification mechanism is employed to avoid early convergence, whilst the intensification mechanism is employed to exploore the neighbors of a solution more effectively. In this paper, we test our algorithm on post-enrolment course timetabling problem. Experimental results show that our algorithm produces good quality solutions and outperforms some results reported in the literature (with regards to Socha's instances) including other ant system algorithms. Therefore, we can conclude that our elitist-ant system has performed an efficient problem's specific knowledge exploitation, and an effective guided search exploration to obtain better quality solutions.

Jaradat, Ghaith M.; Ayob, Masri

48

AN EXPERIMENTAL STUDY OF AN ANT-COLONY ALGORITHM FOR THE MESH-PARTITIONING PROBLEM  

E-print Network

computationally intensive numerical methods such as finite-volume and finite-element methods for solving partial. Introduction. Finite-element methods (FEMs) are a powerful way of solving general prob- lems relating problem, which is known to be an NP -hard. Ant-colony algorithm (ACA) is a relatively new metaheuristic

Silc, Jurij

49

AN ANT COLONY OPTIMIZATION APPROACH FOR THE CAPACITATED VEHICLE ROUTING PROBLEM WITH  

E-print Network

in the sense that each unit consumes the same amount of vehicle capacity. Delivery and pick-up locations DELIVERY AND PICK-UP Bülent �atay1 Abstract. We propose an Ant Colony Optimization (ACO) algorithm to the NP- hard Vehicle Routing Problem with Simultaneous Delivery and Pick-up (VRPSDP). In VRPSDP

Yanikoglu, Berrin

50

A Solution of Dynamic Vehicle Routing Problem with Time Window via Ant Colony System Metaheuristic  

Microsoft Academic Search

This paper addresses an architecture for solving the dynamic vehicle routing problem with time windows(DVRPTW) and capacitated fleet using the ant colony system(ACS) metaheuristic. All customers are known in advance,but their demands take place at any instant within a time horizon. The architecture has been developed to run in a centralized fashion, having two main elements, i.e, the events manager

Sabrina Moreira De Oliveira; Sérgio Ricardo De Souza; Maria Amélia Lopes Silva

2008-01-01

51

An efficient ant colony optimization system for the manufacturing cells formation problem  

Microsoft Academic Search

An ant colony optimization (ACO) scheme for the manufacturing cells design problem is proposed, which uses a tight eigenvalue-based\\u000a bound to guide and accelerate the search. This feature is combined with a good initialization procedure and with ideas from\\u000a successful ACO implementations in other areas, to achieve efficiency and reliability with the minimum structure and set of\\u000a parameters. The resulting

K. Spiliopoulos; S. Sofianopoulou

2008-01-01

52

A modify ant colony optimization for the grid jobs scheduling problem with QoS requirements  

NASA Astrophysics Data System (ADS)

Job scheduling with customers' quality of service (QoS) requirement is challenging in grid environment. In this paper, we present a modify Ant colony optimization (MACO) for the Job scheduling problem in grid. Instead of using the conventional construction approach to construct feasible schedules, the proposed algorithm employs a decomposition method to satisfy the customer's deadline and cost requirements. Besides, a new mechanism of service instances state updating is embedded to improve the convergence of MACO. Experiments demonstrate the effectiveness of the proposed algorithm.

Pu, Xun; Lu, XianLiang

2011-10-01

53

A New Local Search Based Ant Colony Optimization Algorithm for Solving Combinatorial Optimization Problems  

NASA Astrophysics Data System (ADS)

Ant Colony Optimization (ACO) algorithms are a new branch of swarm intelligence. They have been applied to solve different combinatorial optimization problems successfully. Their performance is very promising when they solve small problem instances. However, the algorithms' time complexity increase and solution quality decrease for large problem instances. So, it is crucial to reduce the time requirement and at the same time to increase the solution quality for solving large combinatorial optimization problems by the ACO algorithms. This paper introduces a Local Search based ACO algorithm (LSACO), a new algorithm to solve large combinatorial optimization problems. The basis of LSACO is to apply an adaptive local search method to improve the solution quality. This local search automatically determines the number of edges to exchange during the execution of the algorithm. LSACO also applies pheromone updating rule and constructs solutions in a new way so as to decrease the convergence time. The performance of LSACO has been evaluated on a number of benchmark combinatorial optimization problems and results are compared with several existing ACO algorithms. Experimental results show that LSACO is able to produce good quality solutions with a higher rate of convergence for most of the problems.

Hassan, Md. Rakib; Islam, Md. Monirul; Murase, Kazuyuki

54

Fuzzy Random ?-Mean SAD Portfolio Selection Problem: An Ant Colony Optimization Approach  

NASA Astrophysics Data System (ADS)

To reach the investment goal, one has to select a combination of securities among different portfolios containing large number of securities. Only the past records of each security do not guarantee the future return. As there are many uncertain factors which directly or indirectly influence the stock market and there are also some newer stock markets which do not have enough historical data, experts' expectation and experience must be combined with the past records to generate an effective portfolio selection model. In this paper the return of security is assumed to be Fuzzy Random Variable Set (FRVS), where returns are set of random numbers which are in turn fuzzy numbers. A new ?-Mean Semi Absolute Deviation (?-MSAD) portfolio selection model is developed. The subjective opinions of the investors to the rate of returns of each security are taken into consideration by introducing a pessimistic-optimistic parameter vector ?. ?-Mean Semi Absolute Deviation (?-MSAD) model is preferred as it follows absolute deviation of the rate of returns of a portfolio instead of the variance as the measure of the risk. As this model can be reduced to Linear Programming Problem (LPP) it can be solved much faster than quadratic programming problems. Ant Colony Optimization (ACO) is used for solving the portfolio selection problem. ACO is a paradigm for designing meta-heuristic algorithms for combinatorial optimization problem. Data from BSE is used for illustration.

Thakur, Gour Sundar Mitra; Bhattacharyya, Rupak; Mitra, Swapan Kumar

2010-10-01

55

Ant System Thomas Stutzle  

E-print Network

¡£¢ ­ ¤¦¥ Ant System Thomas St¨utzle § Universit´e Libre de Bruxelles IRIDIA Brussels, Belgium Ant System, the first Ant Colony Optimization algorithm, showed to be a viable method for attacking Problem. To show that Ant Colony Opti- mization algorithms could be good alternatives to existing

Hoos, Holger H.

56

Ant-Q: A Reinforcement Learning Approach to the Traveling Salesman Problem  

Microsoft Academic Search

In this paper we introduce Ant-Q, a family of algorithms which present many similarities with Q-learning (Watkins, 1989), and which we apply to the solution of symmetric and asym- metric instances of the traveling salesman prob- lem (TSP). Ant-Q algorithms were inspired by work on the ant system (AS), a distributed algo- rithm for combinatorial optimization based on the metaphor

Luca Maria Gambardella; Marco Dorigo

1995-01-01

57

Ant Programming: Or how to use ants for automatic programming  

E-print Network

Ant Programming: Or how to use ants for automatic programming Olivier ROUX, Cyril FONLUPT,fonlupt�@lil.univ­littoral.fr Abstract Ant Programming (AP) is a new method which applies the principle of the ants systems for the resolution of com­ binatorial optimization problems. Among the most recent work have emerged the ants systems

Fernandez, Thomas

58

Ant Colony Optimization  

NSDL National Science Digital Library

The Ant Colony Optimization project uses the behavior of ants as a model to solve optimization problems, such as how to minimize Internet traffic congestion. Several downloadable research papers are included on the project's homepage, as well as links to news stories, radio broadcasts, and conference proceedings about ant algorithms.

Dorigo, Marco

2008-01-04

59

An Ant Colony Optimization Approach to Solve Cooperative Transportation Planning Problems  

Microsoft Academic Search

In this paper, we suggest efficient heuristics to solve a cooperative transportation planning problem that is motivated by a scenario found in the German food industry. After an appropriate decomposition of the entire problem into sub problems, we obtain a set of rich vehicle routing problems (VRP) including due dates for the delivery of the orders, capacity constraints and maximum

Ralf Sprenger; Lars Mönch

2009-01-01

60

Ant hill  

NSDL National Science Digital Library

Ants build ant hills as a result of digging underground. They dig several different chambers underground to live in and raise young ants in. As they make these chambers, the ants bring the unneeded soil to the surface, forming what we see as an ant hill.

Peter N/A (None;)

2006-01-10

61

Honey Ants.  

ERIC Educational Resources Information Center

Provides background information on honey ants. These ants are found in dry or desert regions of North America, Africa, and Australia. Also provides a list of activities using local species of ants. (JN)

Conway, John R.

1984-01-01

62

AN ANT COLONY SYSTEM APPROACH FOR SOLVING THE AT-LEAST VERSION OF THE GENERALIZED MINIMUM SPANNING TREE PROBLEM  

E-print Network

AN ANT COLONY SYSTEM APPROACH FOR SOLVING THE AT-LEAST VERSION OF THE GENERALIZED MINIMUM SPANNING-hard. In this paper, we pro- pose an ant colony system based solution approach for the L-GMST. A key feature of our algorithm is its use of ants of different behavioral characteristics, which are adapted over time

Arabshahi, Payman

63

Framing a Philosophy of Environmental Action: Aldo Leopold, John Muir, and the Importance of Community  

ERIC Educational Resources Information Center

A philosophy of action consists of a theory about how and why we do things and what motivates us to act. By juxtaposing the theory of environmental action implied by the works and life of John Muir with the philosophy of action suggested by Aldo Leopold's Land Ethic, we will illuminate the importance of a philosophy of action in determining one's…

Goralnik, Lissy; Nelson, Michael P.

2011-01-01

64

At-Least Version of the Generalized Minimum Spanning Tree Problem: Optimization Through Ant Colony System and Genetic Algorithms  

NASA Technical Reports Server (NTRS)

The At-Least version of the Generalized Minimum Spanning Tree Problem (L-GMST) is a problem in which the optimal solution connects all defined clusters of nodes in a given network at a minimum cost. The L-GMST is NPHard; therefore, metaheuristic algorithms have been used to find reasonable solutions to the problem as opposed to computationally feasible exact algorithms, which many believe do not exist for such a problem. One such metaheuristic uses a swarm-intelligent Ant Colony System (ACS) algorithm, in which agents converge on a solution through the weighing of local heuristics, such as the shortest available path and the number of agents that recently used a given path. However, in a network using a solution derived from the ACS algorithm, some nodes may move around to different clusters and cause small changes in the network makeup. Rerunning the algorithm from the start would be somewhat inefficient due to the significance of the changes, so a genetic algorithm based on the top few solutions found in the ACS algorithm is proposed to quickly and efficiently adapt the network to these small changes.

Janich, Karl W.

2005-01-01

65

An ant colony optimisation algorithm for the 2D and 3D hydrophobic polar protein folding problem  

PubMed Central

Background The protein folding problem is a fundamental problems in computational molecular biology and biochemical physics. Various optimisation methods have been applied to formulations of the ab-initio folding problem that are based on reduced models of protein structure, including Monte Carlo methods, Evolutionary Algorithms, Tabu Search and hybrid approaches. In our work, we have introduced an ant colony optimisation (ACO) algorithm to address the non-deterministic polynomial-time hard (NP-hard) combinatorial problem of predicting a protein's conformation from its amino acid sequence under a widely studied, conceptually simple model – the 2-dimensional (2D) and 3-dimensional (3D) hydrophobic-polar (HP) model. Results We present an improvement of our previous ACO algorithm for the 2D HP model and its extension to the 3D HP model. We show that this new algorithm, dubbed ACO-HPPFP-3, performs better than previous state-of-the-art algorithms on sequences whose native conformations do not contain structural nuclei (parts of the native fold that predominantly consist of local interactions) at the ends, but rather in the middle of the sequence, and that it generally finds a more diverse set of native conformations. Conclusions The application of ACO to this bioinformatics problem compares favourably with specialised, state-of-the-art methods for the 2D and 3D HP protein folding problem; our empirical results indicate that our rather simple ACO algorithm scales worse with sequence length but usually finds a more diverse ensemble of native states. Therefore the development of ACO algorithms for more complex and realistic models of protein structure holds significant promise. PMID:15710037

Shmygelska, Alena; Hoos, Holger H

2005-01-01

66

The role of ex ante regulations in addressing problems of moral hazard in agricultural insurance  

Microsoft Academic Search

We develop a theoretical model of input use by agricultural producers who purchase crop insurance, and thus may engage in moral hazard. Through simulations, our findings show a combination of partial insurance coverage and partial monitoring of inputs may reduce substantially the problems associated with moral hazard. The minimum level of input use that must be required by regulation is

Calum G. Turvey; Michael Hoy; Zahirul Islam

2002-01-01

67

An Improved Ant Colony Algorithm for Order Picking Optimization Problem in Automated Warehouse  

Microsoft Academic Search

Automated storage and retrieval system (AS\\/RS) is being widely used in the logistics industry. The order picking problem is\\u000a researched to improve the overall efficiency of the system. A mathematical model is constructed to obtain the minimal travel\\u000a time during the retrieval and storage operation under the operating condition that each machine serves several aisles of the\\u000a system. The aisles

Hai-yan Tang; Mei-juan Li

68

Ant Colony Optimization From Scholarpedia  

E-print Network

Ant Colony Optimization From Scholarpedia From Scholarpedia, the free peer-reviewed encyclopedia p.18620 Curator: Marco Dorigo, IRIDIA, Université Libre de Bruxelles, Brussels, Belgium Ant colony to difficult optimization problems. In ACO, a set of software agents called artificial ants search for good

Libre de Bruxelles, Université

69

MAX-MIN Ant System  

Microsoft Academic Search

Abstract Ant System, the first Ant Colony Optimization algorithm, showed to be a viable method for attacking hard combinatorial optimization problems. Yet, its performance, when compared to more fine-tuned algorithms, was rather poor for large instances of traditional benchmark,problems,like the Traveling Salesman Problem. To show that Ant Colony Optimization algorithms could be good alternatives to existing algorithms for hard combinatorial

Thomas Stützle; Holger H. Hoos

2000-01-01

70

Harvester ants  

NSDL National Science Digital Library

Shows several different views of harvester ants, a major food source of the Texas horned lizard. The video is large and a highspeed connection is recommended. The video shows ants entering their nest and moving on pathways that have been cleared of debris. The nest entrance has guards that are checking each of the returning ants.

0002-11-30

71

The Ant Colony Optimization MetaHeuristic  

Microsoft Academic Search

IntroductionAnt algorithms are multi-agent systems in which the behavior of each single agent, calledartificial ant or ant for short in the following, is inspired by the behavior of real ants. Antalgorithms are one of the most successful examples of swarm intelligent systems [3], andhave been applied to many types of problems, ranging from the classical traveling salesmanproblem, to routing in

Marco Dorigo; Gianni Di Caro

1999-01-01

72

Reticulated acanthoma with sebaceous differentiation: another sebaceous neoplasm associated with Muir-Torre syndrome?  

PubMed

Reticulated acanthoma with sebaceous differentiation (RASD) represents a rare benign cutaneous epithelial neoplasm with sebaceous differentiation. There has been much speculation about the relationship between RASD and Muir-Torre syndrome (MTS). We report a 53 year-old man who presented with RASD in addition to a prior history of sebaceous adenomas. Immunohistochemically, the tumour cells in the RASD and sebaceous adenomas showed a significantly reduced MSH6 protein expression, whereas there was no loss of MLH1, MSH2 and PMS2. This benign neoplasm, which can be mistaken for various other cutaneous lesions with sebaceous differentiation, deserves wider recognition for its possible association with MTS. PMID:23651324

Shon, Wonwoo; Wolz, Michael M; Newman, Catherine C; Bridges, Alina G

2014-11-01

73

Fire ants  

MedlinePLUS

Fire ants are red-colored insects that sting and deliver a harmful substance, called venom, into your skin. This is for information only and not for use in the treatment or management of an actual poison exposure. If ...

74

Farming ants run microbe motels  

NSDL National Science Digital Library

The ants that grow fungus in little gardens face a problem that is well known to human farmers - pests. Scientists have just discovered that farming ants are covered in little "motel rooms" that serve as shelter for bacteria that protect their crops.

American Association for the Advancement of Science (AAAS; )

2006-01-05

75

The genetic basis of Muir-Torre syndrome includes the hMLH1 locus  

SciTech Connect

Muir-Torre syndrome (MTS) (McKusick 158320) is an autosomal dominant disorder characterized by the development of sebaceous gland tumors and skin cancers, including keratoacanthomas and basal cell carcinomas. Affected family members may manifest a wide spectrum of internal malignancies, which include colorectal, endometrial, urologic, and upper gastrointestinal neoplasms. Sebaceous gland tumors, which are rare in the general population, are considered to be the hallmark of MTS and may arise prior to the development of other visceral cancers. Despite the high incidence of synchronous and metachronous tumors, prognosis is often favorable. Hereditary nonpolyposis colorectal cancer (HNPCC) is one of the most common autosomal dominantly inherited colorectal cancer susceptibility syndromes. In some HNPCC families, extracolonic tumors of the endometrium, ovary, small bowel, and renal and biliary tract occur at an increased frequency. On the basis of similarities in clinical symptoms of MTS and HNPCC, it is proposed that these two syndromes may have a common genetic basis. 24 refs., 2 figs.

Bapat, B.; Xia, L.; Mitri, A. [Univ. of Toronto (Canada)] [and others

1996-09-01

76

Understanding and managing experiential aspects of soundscapes at Muir woods national monument.  

PubMed

Research has found that human-caused noise can detract from the quality of the visitor experience in national parks and related areas. Moreover, impacts to the visitor experience can be managed by formulating indicators and standards of quality as suggested in park and outdoor recreation management frameworks, such as Visitor Experience and Resource Protection (VERP), as developed by the U.S. National Park Service. The research reported in this article supports the formulation of indicators and standards of quality for human-caused noise at Muir Woods National Monument, California. Phase I identified potential indicators of quality for the soundscape of Muir Woods. A visitor "listening exercise" was conducted, where respondents identified natural and human-caused sounds heard in the park and rated the degree to which each sound was "pleasing" or "annoying." Certain visitor-caused sounds such as groups talking were heard by most respondents and were rated as annoying, suggesting that these sounds may be a good indicator of quality. Loud groups were heard by few people but were rated as highly annoying, whereas wind and water were heard by most visitors and were rated as highly pleasing. Phase II measured standards of quality for visitor-caused noise. Visitors were presented with a series of 30-second audio clips representing increasing amounts of visitor-caused sound in the park. Respondents were asked to rate the acceptability of each audio clip on a survey. Findings suggest a threshold at which visitor-caused sound is judged to be unacceptable, and is therefore considered as noise. A parallel program of sound monitoring in the park found that current levels of visitor-caused sound sometimes violate this threshold. Study findings provide an empirical basis to help formulate noise-related indicators and standards of quality in parks and related areas. PMID:19020928

Pilcher, Ericka J; Newman, Peter; Manning, Robert E

2009-03-01

77

Path Integration in Desert Ants, Cataglyphis fortis  

Microsoft Academic Search

Foraging desert ants, Cataglyphis fortis, continually keep track of their own positions relative to home--i.e., integrate their tortuous outbound routes and return home along straight (inbound) routes. By experimentally manipulating the ants' outbound trajectories we show that the ants solve this path integration problem not by performing a true vector summation (as a human navigator does) but by employing a

Martin Muller; Rudiger Wehner

1988-01-01

78

Management of Imported Fire Ants in Cattle Production Systems  

E-print Network

ANR-1248 ALABAMA A&M AND AUBURN UNIVERSITIES Management of Imported Fire Ants in Cattle Production Systems I mported fire ants are now a major pest problem throughout the southeastern United States, including in cattle production operations (Figures... the Alabama Cooperative Extension System: ANR-175, ?Imported Fire Ants in Lawns, Turf, and Structures?; ANR-175-A, ?Fire Ant Control Materials for Homeowners?; ANR-1149, ?Biological Control of Fire Ants?; ANR-1161, ?Getting the Most Out of Your Fire Ant Bait...

Fuchs, Thomas W.; Drees, Bastiaan M.

2004-03-31

79

Pest Ants and Cockroaches  

NSDL National Science Digital Library

Tutorials on pest ants and cockroaches. Each tutorial has 50 questions; incorrect answers lead to additional information. Covers acrobat ant, Argentine ant, bigheaded ant, crazy ant, Florida carpenter ant, ghost ant, imported fire ant, little fire ant, native fire ant and Pharaoh ant, American cockroach, Australian cockroach, brown cockroach, brownbanded cockroach, Cuban cockroach, Florida woods cockroaches, German cockroach, oriental cockroach, smokybrown cockroach and Surinam cockroach. Requires Windows. program must be downloaded on to hardrive, but once installed is intuitive. many of the species depicted in these tutorials are restricted to Florida and the extreme southern U.S. $15. Part number SW 157.

0002-11-30

80

Ant Database  

NSDL National Science Digital Library

Research entomologist Ted Schultz from the Smithsonian Institution maintains this impressive work in progress. This online database represents the Smithsonian's identified ant collection, including 4,580 valid named species or subspecies. The taxonomy is current with Bolton's 1995 catalog and includes reported holdings through June 1998. The database may be queried by Subfamily, Tribe, Genus, Subgenus, Species, Subspecies, Author, or Types, and typical returns give concise taxonomic information, total specimens (workers, females, and males), author, and year.

Schultz, Ted.

2000-01-01

81

Parallelization Strategies for the Ant System  

Microsoft Academic Search

. The Ant System is a new meta-heuristic method particularly appropriate to solve hard combinatorial optimization problems. It is a population-based, nature-inspired approach exploiting positive feedback as well as local information and has been applied successfully to a variety of combinatorial optimization problems. The Ant System consists of a set of cooperating agents (artificial ants) and a set of rules

Bernd Bullnheimer; Gabriele Kotsis; Christine Strauß

1998-01-01

82

Ant nebula  

NASA Technical Reports Server (NTRS)

A new Hubble Space Telescope image of a celestial object called the Ant Nebula may shed new light on the future demise of our Sun. The image is available at http://www.jpl.nasa.gov/pictures/wfpc .

The nebula, imaged on July 20, 1997, and June 30, 1998, by Hubble's Wide Field and Planetary Camera 2, was observed by Drs. Raghvendra Sahai and John Trauger of NASA's Jet Propulsion Laboratory, Pasadena, Calif.; Bruce Balick of the University of Washington in Seattle; and Vincent Icke of Leiden University in the Netherlands. JPL designed and built the camera.

The Ant Nebula, whose technical name is Mz3, resembles the head and thorax of an ant when observed with ground-based telescopes. The new Hubble image, with 10 times the resolution revealing 100 times more detail, shows the 'ant's' body as a pair of fiery lobes protruding from a dying, Sun- like star. The Ant Nebula is located between 3,000 and 6,000 light years from Earth in the southern constellation Norma.

The image challenges old ideas about what happens to dying stars. This observation, along with other pictures of various remnants of dying stars called planetary nebulae, shows that our Sun's fate will probably be much more interesting, complex and dramatic than astronomers previously believed.

Although the ejection of gas from the dying star in the Ant Nebula is violent, it does not show the chaos one might expect from an ordinary explosion, but instead shows symmetrical patterns. One possibility is that the central star has a closely orbiting companion whose gravitational tidal forces shape the outflowing gas. A second possibility is that as the dying star spins, its strong magnetic fields are wound up into complex shapes like spaghetti in an eggbeater. Electrically charged winds, much like those in our Sun's solar wind but millions of times denser and moving at speeds up to 1,000 kilometers per second (more than 600 miles per second) from the star, follow the twisted field lines on their way out into space.

The Space Telescope Science Institute, Baltimore, Md., manages space operations for the Hubble Space Telescope for NASA's Office of Space Science, Washington, D.C. The Institute is operated by the Association of Universities for Research in Astronomy, Inc., for NASA under contract with NASA's Goddard Space Flight Center, Greenbelt, Md. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. JPL is a division of the California Institute of Technology in Pasadena.

Additional information about the Hubble Space Telescope is available at http://www.stsci.edu . More information about the Wide Field and Planetary Camera 2 is available at http://wfpc2.jpl.nasa.gov.

1999-01-01

83

Ant Colonies for the QAP  

Microsoft Academic Search

This paper presents HAS-QAP, an hybrid ant colony system coupled with a local search, applied to thequadratic assignment problem. HAS-QAP uses pheromone trail information to perform modifications onQAP solutions, differently from more traditional ant systems that use pheromone trail information toconstruct complete solutions. HAS-QAP is analysed and compared with some of the best heuristics availablefor the QAP: two taboo search

L. M. Gambardella; É. D. Taillard; M. Dorigo

1997-01-01

84

The Ants Have It!  

ERIC Educational Resources Information Center

Uses the GEMS guide, "Ants at Home Underground", to explore the life of ants and teach about them in a classroom setting. The activity applies students' knowledge of ants and students learn about ant colonies, what ants eat, and how they live. (SAH)

Daugherty, Belinda

2001-01-01

85

Fire Ant Bites  

MedlinePLUS

... Favorite Name: Category: Share: Yes No, Keep Private Fire Ant Bites Share | Fire ants are aggressive, venomous insects that have pinching ... across the United States, even into Puerto Rico. Fire ant stings usually occur on the feet or ...

86

The Ant Colony Metaphor for Searching Continuous Design Spaces  

Microsoft Academic Search

This paper describes a form of dynamical computational system—the ant colony—and presents an ant colony model for continuous space optimisation problems. The ant colony metaphor is applied to a real world heavily constrained engineering design problem. It is capable of accelerating the search process and finding acceptable solutions which otherwise could not be discovered by a GA. By integrating the

George Bilchev; Ian C. Parmee

1995-01-01

87

Fire Ants and Thelohania Fire Ant Disease  

NSDL National Science Digital Library

Excellent summary of how Thelohania fire ant disease works as a biological control measure against fire ants. Unhurried pace with great supporting video and graphics. Good choice for introducing students to the idea of biological control. Video quality is excellent. This video should probably be used in conjunction with the other two fire ant biocontrol videos produced by the same workers.

0002-11-30

88

Evaluation of conditions along the grounding line of temperate marine glaciers: An example from Muir Inlet, Glacier Bay, Alaska  

USGS Publications Warehouse

In the marine environment, stability of the glacier terminus and the location of subglacial streams are the dominant controls on the distribution of grounding-line deposits within morainal banks. A morainal bank complex in Muir Inlet, Glacier Bay, SE Alaska, is used to develop a model of terminus stability and location of subglacial streams along the grounding line of temperate marine glaciers. This model can be used to interpret former grounding-line conditions in other glacimarine settings from the facies architecture within morainal bank deposits. The Muir Inlet morainal bank complex was deposited between 1860 A.D. and 1899 A.D., and historical observations provide a record of terminus positions, glacial retreat rates and sedimentary sources. These data are used to reconstruct the depositional environment and to develop a correlation between sedimentary facies and conditions along the grounding line. Four seismic facies identified on the high-resolution seismic-reflection profiles are used to interpret sedimentary facies within the morainal bank complex. Terminus stability is interpreted from the distribution of sedimentary facies within three distinct submarine geomorphic features, a grounding-line fan; stratified ridges, and a field of push ridges. The grounding-line fan was deposited along a stable terminus and is represented on seismic-reflection profiles by two distinct seismic facies, a proximal and a distal fan facies. The proximal fan facies was deposited at the efflux of subglacial streams and indicates the location of former glacifluvial discharges into the sea. Stratified ridges formed as a result of the influence of a quasi-stable terminus on the distribution of sedimentary facies along the grounding line. A field of push ridges formed along the grounding line of an unstable terminus that completely reworked the grounding-line deposits through glacitectonic deformation. Between 1860 A.D. and 1899 A.D. (39 years), 8.96 x 108 m3 of sediment were deposited within the Muir Inlet morainal bank complex at an average annual sediment accumulation rate of 2.3 x 107 m3/a. This rate represents the annual sediment production capacity of the glacier when the Muir Inlet drainage basin is filled with glacial ice.

Seramur, K.C.; Powell, R.D.; Carlson, P.R.

1997-01-01

89

Ant algorithms and stigmergy  

Microsoft Academic Search

Ant colonies, and more generally social insect societies, are distributed systems that, in spite of the simplicity of their individuals, present a highly structured social organization. As a result of this organization, ant colonies can accomplish complex tasks that in some cases far exceed the individual capacities of a single ant. The study of ant colonies behavior and of their

Marco Dorigo; Eric Bonabeau; Guy Theraulaz

2000-01-01

90

Acacia Tree Ants  

NSDL National Science Digital Library

The phenomenon is the symbiotic relationship between the acacia ant and the swollen thorn acacia tree, shown in a 2:18 minute video. The ant provides protection for the tree against preying insects and other plants competing for sunlight, and the tree provides nourishment and shelter for the ant and the ants' larvae.

91

“Anting” in Blue Jays  

PubMed Central

Summary Anting, the plumage-dipping behavior to which ants (mostly formicines) are commonly subjected by birds (mostly passerines), is shown in tests with hand-raised Blue Jays (Cyanocitta cristata) and the ant Formica exsectoides to be instinctive: the birds displayed typical renditions of the behavior on the first occasion that they encountered ants. Evidence is presented supportive of the view that anting is a strategy by which birds render ants fit for ingestion. Formicine ants are ordinarily protected by their formic acid-containing spray. Being wiped into the bird’s plumage causes them to discharge that spray, without harm to the bird, to the point of almost total emptying of the glandular sac in which the secretion is stored. The ants are therefore essentially secretion-free by the time they are swallowed. Further evidence indicates that it is the ant’s possession of the acid sac that triggers the anting behavior in the bird. If F. exsectoides are surgically deprived of their acid sac, they are eaten by the birds without first being subjected to anting. Data are also presented indicating that the ant’s crop, which is especially capacious in formicines (its contents may amount to over 30% of the formicine’s mass), and which appears to survive the anting procedure intact, constitutes, at least when laden, a valuable component of the trophic package that the bird accesses by anting. PMID:19169379

Eisner, Thomas; Aneshansley, Daniel

2008-01-01

92

THE IMPORTED FIRE ANTS AND THEIR MANAGEMENT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Imported fire ants (IFA) cause many problems for humans, domestic animals, and agriculture. Imported fire ants are very aggressive, build conspicuous mounds, and have a sting that gives a burning sensation. IFAs have also had a major impact on wildlife and their effects on quail populations can be s...

93

Red Harvester Ants  

E-print Network

. ? Horned lizards normally inhabit flat, open, dry country with little cover. Urbanization, mowing, shredding, shallow discing and other land use practices can eliminate or reduce the production of weed seeds on which harvester ants feed. Harvester ants... Entomologist, The Texas A&M University System. Red harvester ants Food sources Red harvester ant foragers collect seeds and dead insects and store them in the nests as food for the colony. The ants? mouthparts are designed for chewing. Management Red...

Drees, Bastiaan M.

2006-04-24

94

How Many Ants Does It Take To Find the Food? Yuval Emek1  

E-print Network

How Many Ants Does It Take To Find the Food? Yuval Emek1 , Tobias Langner2 , David Stolz2 , Jara the Ants Nearby Treasure Search (ANTS) problem, where n mobile agents, initially placed at the origin constant-size mes- sages. We show that the minimum number of agents required to solve the ANTS problem

95

Fire Ants and Their Control.  

E-print Network

fire ant control usually are labeled only for certain treatment sites. The techniques for applying these products also vary with the treatment sites. Care must be taken to select the best combination of control agents and application methods... in each situation to attain optimum results. The Non-Control Option - Why Consider it? In areas where fire ants are not causing a problem, it may be best not to attempt any control measures. The reason is that a unit area, sue as an acre ofland, ill...

Hamman, Philip J.; Drees, Bastiaan M.; Vinson, S. Bradleigh

1986-01-01

96

Ant colony optimization with the characteristic of social work division  

Microsoft Academic Search

In order to solve the continuous space optimization problems, an ant colony optimization with the characteristic of social work division is presented. The decimal coding rule of the variables in continuous space is explained. The paper presents six behaviors of artificial ant, the function of the promotion team ant colony and the three-dimensional coordinate pheromone system. Computer simulation results indicate

Li Xinxin; Luo Yi; Zhang Juntao

2008-01-01

97

Fire Ants Photos  

MedlinePLUS

Share | Photos & Graphics: Fire Ants Please attribute all images as follows: Source: The Journal of Allergy and Clinical Immunology. ... visit the National Allergy Bureau's Plant and Pollen Photo Gallery . Solenopsis invicta worker ants and queen. Arranged ...

98

Structure of the human MSH2 locus and analysis of two Muir-Torre kindreds for msh2 mutations  

SciTech Connect

Hereditary nonpolyposis colorectal carcinoma (HNPCC) is a major cancer susceptibility syndrome known to be caused by inheritance of mutations in genes such as hMSH2 and hMLH1, which encode components of a DNA mismatch repair system. The MSH2 genomic locus has been cloned and shown to cover {approximately}73 kb of genomic DNA and to contain 16 exons. The sequence of all of the intron-exon junctions has been determined and used to develop methods for analyzing each MSH2 exon for mutations. These methods have been used to analyze two large HNPCC kindreds exhibiting features of the Muir-Torre syndrome and demonstrate that cancer susceptibility is due to the inheritance of a frameshift mutation in the MSH2 gene in one family and a nonsense mutation in the MSH2 gene in the other family. 59 refs., 5 figs., 1 tab.

Kolodner, R.D.; Lipford, J.; Kane, M.F. [Dana-Farber Cancer Institute, Boston, MA (United States)] [and others] [Dana-Farber Cancer Institute, Boston, MA (United States); and others

1994-12-01

99

Fire ant trail  

NSDL National Science Digital Library

Fire ants mark their trail with a substance from the Dufour's gland. The trail used by a group of fire ants is shown. Several examples of groups of ants following each other are shown. File size is large and a highspeed connection is recommended.

0002-11-30

100

Steve Yanoviak's Gliding Ants  

NSDL National Science Digital Library

Home page of the gliding ant research of Steve Yanoviak including many videos of ants falling and swerving back to the tree, comparison videos of non-gliding ants are given for comparison. This is a fascinating insect behavior that may be an evolutionary step in insect flight.

0002-11-30

101

Fire Ant Allergy  

MedlinePLUS

Share | Fire Ant Allergy This article has been reviewed by Thanai Pongdee, MD, FAAAAI Fire ants are a stinging insect typically found in ... a Serious Reaction For people with fire ant allergy, stings may cause a life-threatening reaction called ...

102

Fire Ants: Ecological Bullies  

NSDL National Science Digital Library

This two-minute radio program looks at factors that contribute to Brazilian fire ants' dominance over native ant species in the southeastern United States. An ecologist describes some of these factors, including a lack of control agents, which allow Brazilian fire ants to out compete local ants. The program includes examples of the sounds that Brazilian fire ants use to help coordinate their invasions. The archived program, part of the Pulse of the Planet radio show, is available here in text and audio formats. Copyright 2005 Eisenhower National Clearinghouse

Pulse of the Planet

2007-01-26

103

An Analysis of Human Pathogens Found in Horse\\/Mule Manure Along the John Muir Trail in Kings Canyon and Sequoia and Yosemite National Parks  

Microsoft Academic Search

Objective.—To determine the prevalence of microorganisms that are potentially pathogenic for humans in horse\\/mule manure along the John Muir Trail (JMT). Methods.—Random samples of horse\\/mule manure were collected along sections of the JMT in Yosemite, Kings Canyon, and Sequoia national parks (NP), as well as in portions of the Pacific Crest Trail (PCT) and selected JMT\\/PCT access trails. Convenience samples

Robert Wayne Derlet; James Reynolds Carlson

2002-01-01

104

Ants of Borneo  

NSDL National Science Digital Library

The names Aenictinae, Ceraphachyine, Dorylinae, and Dolichoderinae may not mean much to those outside the world of entomology, but these are but a few of the subfamilies of ants profiled on this nice website designed by Martin Pfeiffer of the University of Ulm. These subfamilies of ants are all present in Kinabulu National Park in Malaysia, a tropical rainforest that has the notable distinction of containing the world's most diverse ant population. Visitors to the site can browse images of over 130 species of ants (divided by their respective subfamily), presented in more than 520 high resolution photographs. Culled from the work of a number of different researchers, the ants photographed for this site were mostly collected during fieldwork that took place between 1991 and 2002. Those persons unfamiliar with the world of the ants of Borneo will have a most intimate understanding of these fascinating creatures and some sense of their sheer diversity after traversing this site.

Pfeiffer, Martin

105

Ant colony optimization for resource-constrained project scheduling  

Microsoft Academic Search

An ant colony optimization approach (ACO) for the resource-constrained project schedul- ing problem (RCPSP) is presented. Combi- nations of two pheromone evaluation meth- ods are used by the ants to find new solutions. We tested our ACO algorithm on a set of large benchmark problems from the PSPLIB. Compared to several other heuristics for the RCPSP including genetic algorithms, simu-

Daniel Merkle; Martin Middendorf; Hartmut Schmeck

2002-01-01

106

Modeling the dynamics of ant colony optimization.  

PubMed

The dynamics of Ant Colony Optimization (ACO) algorithms is studied using a deterministic model that assumes an average expected behavior of the algorithms. The ACO optimization metaheuristic is an iterative approach, where in every iteration, artificial ants construct solutions randomly but guided by pheromone information stemming from former ants that found good solutions. The behavior of ACO algorithms and the ACO model are analyzed for certain types of permutation problems. It is shown analytically that the decisions of an ant are influenced in an intriguing way by the use of the pheromone information and the properties of the pheromone matrix. This explains why ACO algorithms can show a complex dynamic behavior even when there is only one ant per iteration and no competition occurs. The ACO model is used to describe the algorithm behavior as a combination of situations with different degrees of competition between the ants. This helps to better understand the dynamics of the algorithm when there are several ants per iteration as is always the case when using ACO algorithms for optimization. Simulations are done to compare the behavior of the ACO model with the ACO algorithm. Results show that the deterministic model describes essential features of the dynamics of ACO algorithms quite accurately, while other aspects of the algorithms behavior cannot be found in the model. PMID:12227995

Merkle, Daniel; Middendorf, Martin

2002-01-01

107

Leaf cutter ants  

NSDL National Science Digital Library

There is much diversity between ants. Leaf cutter ants use their mandibles to cut leaf fragments and take them back to their home. They don't eat the leaves, but instead use them to grow fungus on. They then eat the fungus.

N/A N/A (None;)

2007-12-15

108

The Ants Have It!  

NSDL National Science Digital Library

This memorable activity creatively applied students' knowledge of ants--and it all started with a wonderful Lawrence Hall GEMS guide and a teacher with a sweet tooth. The students learned that the success of the colony depends on each ant doing its job. Th

Daugherty, Belinda

2001-02-01

109

Surface water quality along the Central John Muir Trail in the Sierra Nevada Mountains: coliforms and algae.  

PubMed

The John Muir Trail (JMT) in the Sierra Nevada Mountains of California is one of the most popular alpine wilderness trails in the United States, where backpackers depend on trailside water sources for more than 335 km (208 miles). This study addressed the risk of acquiring waterborne disease by analyzing prevalence and changes in coliform bacteria and Escherichia coli (E. coli) in lakes and streams adjacent to the central JMT. Chlorophyll-a levels were also measured as an indicator of high elevation eutrophication. Categories of environmental land use which might affect water quality were defined as: Pristine areas rarely traversed by humans; Backpack off-trail areas not traversed by pack or stock animals; and Multiuse areas with backpacker and animal use. We analyzed surface water at 36 different sites three separate times over an eight week period in the summer of 2008. Chlorophyll-a concentration increased significantly in Backpack and Multiuse sites over the summer months, but not in Pristine sites. Similar results were obtained for coliforms, with prevalence also increasing significantly over the summer months in Backpack and Multiuse sites. There was a much higher prevalence of E. coli in Multiuse sites compared to Pristine and Backpack sites. Our study provides evidence pack and stock animals serve as a source of microbial contamination of water along this section of trail. PMID:20039816

Ursem, Carling; Evans, C Scott; Ger, Kemal Ali; Richards, John R; Derlet, Robert W

2009-01-01

110

An Ant System Approach to Redundancy Allocation Yun-Chia Liang  

E-print Network

An Ant System Approach to Redundancy Allocation Yun-Chia Liang Department of Industrial Engineering and demonstrating a problem-specific Ant System. The problem is to select components and redundancy-levels to maximize system reliability, given system-level constraints on cost and weight. The Ant System algorithm

Smith, Alice E.

111

Osaka-UCSD Workshop 2011 John Muir Room, Price Center East, UC San Diego  

E-print Network

disregarded. In order to reveal their problems and to establish a new design principle for safe and adaptable International), and NICT (National Institute of Information and Communications Technology) in Japan. (http://www.gcoe-cnr.osaka-u.ac:30-13:30 Lunch 13:30-14:30 Human brain-machine interface (BMI) Toshiki Yoshimine, Grad. School of Medicine, Osaka

112

Non?native Ants Are Smaller than Related Native Ants  

Microsoft Academic Search

I compare the sizes of non-native and native ants to evaluate how worker size may be related to the ability of a species to invade new habitats. I compare the size of 78 non-native ant species belonging to 26 genera with the size of native congeneric species; native ants are larger than non-native ants in 22 of 26 genera. Ants

Terrence P. McGlynn

1999-01-01

113

Biological Control of Fire Ants  

NSDL National Science Digital Library

Demonstrates fire ant invasion of the southern United States and two biological control approaches: decapitating flies and disease. Upbeat music and corny graphics may make it similar to DDT videos of yesteryear, but it is valuable to quickly demonstrate the problem to students. The video appears to overstate the potential impact of these biological control agents but is a good, and fairly entertaining, introduction to the topic of biocontrol for the RIA. It will be importantant to use this video in the propoer context.

0002-11-30

114

Chemicalmimicry Male ants disguised by  

E-print Network

Chemicalmimicry Male ants disguised by the queen's bouquet M ales of the tropical ant Cardiocondyla the coexistence and equal mating success of two male morphs. Ants typically mate during short nuptial flights-day-old ants, all four groups were clearly separated (Fig. 1b). We conclude that the odour similarity

Zachos, James

115

Ant Colony Optimization for Control  

Microsoft Academic Search

The very basis of this thesis is the collective behavior of ants in colonies. Ants are an excellent example of how rather simple behavior on a local level can lead to complex behavior on a global level that is beneficial for the individuals. The key in the self-organization of ants is communication through pheromones. When an ant forages for food,

J. M. Van Ast

2010-01-01

116

Ice-proximal sediment dynamics and their effect on the stability of Muir Glacier, Alaska: A case study of non-climatic glacier response  

SciTech Connect

Recent studies have shown that water depth at tidewater termini affect calving rates and, therefore, glacier mass balance and terminus stability. Grounding-line water depths are themselves governed by glacial and marine processes that interact during the formation of morainal bank depocenters. These morainal banks can fluctuate 10s of meters in height within an interval of a few weeks. Recent investigations in Glacier Bay have focused on quantitatively assessing sediment budgets in the ice-proximal environment. The monitoring of morainal banks in upper Muir Inlet has included repeated bathymetric mapping, sediment trap studies, bottom grab sampling, glacier and iceberg sampling, and submersible ROV investigations within 1 km of the terminus. Such relationships are important in interpreting recent changes in the dynamics of Muir Glacier where a century of retreat has been succeeded by quasi stability. The new glacier regime has accompanied basin infilling from approximately 100 m depth to a maximum of 52 m at the grounding line. Two large grounding-line fans have aggraded to deltas and reduced the length of the calving margin from 900 m to 290 m wide. These effects have reduced the ice flow velocities by 45%. Annual morainal bank growth ranged from 10[sup 6] to 10[sup 7] m[sup 3] and is the result of glacifluvial dumping, suspension settling from turbid overflow plumes, debris dumping from ice-cliff and iceberg melting, glacier squeezing and pushing of morainal bank sediment, and sediment gravity flow processes. Each of these processes are an integral facet of the morainal bank dynamics and glacier response. These studies of Muir Glacier indicate that glacier response to sediment dynamics need to be addresses before climatic implications are made.

Hunter, L.E.; Powell, R.D. (Northern Illinois Univ., Dekalb, IL (United States). Dept. of Geology)

1992-01-01

117

Ants and ant scent reduce bumblebee pollination of artificial flowers.  

PubMed

Ants on flowers can disrupt pollination by consuming rewards or harassing pollinators, but it is difficult to disentangle the effects of these exploitative and interference forms of competition on pollinator behavior. Using highly rewarding and quickly replenishing artificial flowers that simulate male or female function, we allowed bumblebees (Bombus impatiens) to forage (1) on flowers with or without ants (Myrmica rubra) and (2) on flowers with or without ant scent cues. Bumblebees transferred significantly more pollen analogue both to and from ant-free flowers, demonstrating that interference competition with ants is sufficient to modify pollinator foraging behavior. Bees also removed significantly less pollen analogue from ant-scented flowers than from controls, making this the first study to show that bees can use ant scent to avoid harassment at flowers. Ant effects on pollinator behavior, possibly in addition to their effects on pollen viability, may contribute to the evolution of floral traits minimizing ant visitation. PMID:24334742

Cembrowski, Adam R; Tan, Marcus G; Thomson, James D; Frederickson, Megan E

2014-01-01

118

Journal of the Chinese Institute of Industrial Engineers, Vol. 23, No. 5, pp. 403-414 (2006) 403 AN ANT COLONY APPROACH TO THE ORIENTEERING  

E-print Network

AN ANT COLONY APPROACH TO THE ORIENTEERING PROBLEM Yun-Chia Liang Department of Industrial Engineering is insensitive to seed, problem instance, problem size and degree of constraint. Keywords: ant colony

Smith, Alice E.

119

Clustering Web Search Results Using Fuzzy Ants  

E-print Network

Clustering Web Search Results Using Fuzzy Ants Steven Schockaert,* Martine De Cock, Chris Cornelis and Uncertainty Modelling Research Unit, Krijgslaan 281 (S9), B-9000 Gent, Belgium Algorithms for clustering Web existing approaches and illustrates how our algorithm can be applied to the problem of Web search results

Gent, Universiteit

120

Alate susceptibility in ants  

PubMed Central

Pathogens are predicted to pose a particular threat to eusocial insects because infections can spread rapidly in colonies with high densities of closely related individuals. In ants, there are two major castes: workers and reproductives. Sterile workers receive no direct benefit from investing in immunity, but can gain indirect fitness benefits if their immunity aids the survival of their fertile siblings. Virgin reproductives (alates), on the other hand, may be able to increase their investment in reproduction, rather than in immunity, because of the protection they receive from workers. Thus, we expect colonies to have highly immune workers, but relatively more susceptible alates. We examined the survival of workers, gynes, and males of nine ant species collected in Peru and Canada when exposed to the entomopathogenic fungus Beauveria bassiana. For the seven species in which treatment with B. bassiana increased ant mortality relative to controls, we found workers were significantly less susceptible compared with both alate sexes. Female and male alates did not differ significantly in their immunocompetence. Our results suggest that, as with other nonreproductive tasks in ant colonies like foraging and nest maintenance, workers have primary responsibility for colony immunity, allowing alates to specialize on reproduction. We highlight the importance of colony-level selection on individual immunity in ants and other eusocial organisms.

Ho, Eddie K H; Frederickson, Megan E

2014-01-01

121

Alate susceptibility in ants.  

PubMed

Pathogens are predicted to pose a particular threat to eusocial insects because infections can spread rapidly in colonies with high densities of closely related individuals. In ants, there are two major castes: workers and reproductives. Sterile workers receive no direct benefit from investing in immunity, but can gain indirect fitness benefits if their immunity aids the survival of their fertile siblings. Virgin reproductives (alates), on the other hand, may be able to increase their investment in reproduction, rather than in immunity, because of the protection they receive from workers. Thus, we expect colonies to have highly immune workers, but relatively more susceptible alates. We examined the survival of workers, gynes, and males of nine ant species collected in Peru and Canada when exposed to the entomopathogenic fungus Beauveria bassiana. For the seven species in which treatment with B. bassiana increased ant mortality relative to controls, we found workers were significantly less susceptible compared with both alate sexes. Female and male alates did not differ significantly in their immunocompetence. Our results suggest that, as with other nonreproductive tasks in ant colonies like foraging and nest maintenance, workers have primary responsibility for colony immunity, allowing alates to specialize on reproduction. We highlight the importance of colony-level selection on individual immunity in ants and other eusocial organisms. PMID:25540683

Ho, Eddie K H; Frederickson, Megan E

2014-11-01

122

Muir-Torre syndrome or phenocopy? The value of the immunohistochemical expression of mismatch repair proteins in sebaceous tumors of immunocompromised patients.  

PubMed

Primary and secondary immunodepressive conditions are associated with an increased incidence of sebaceous tumors. Microsatellite instability (MSI) and lack of expression of mismatch repair (MMR) proteins, typical markers of Muir-Torre/Lynch heredo-familial settings, can be recognized also in immunocompromised patients. We aimed to carry on a systematic examination of clinical, immunohistochemical, biomolecular features of sebaceous tumors arising in immunocompromised and immunocompetent patients between 1986 and 2012. Microsatellite screening, immunohistochemical analysis and genetic testing were performed for hMLH1, hMSH2 and hMSH6. Methylation status of MMR genes was checked in cases with immunohistochemistry (IHC) loss of MMR proteins expression and no germline mutations. Fifteen patients had a personal history of visceral carcinomas fulfilling diagnostic criteria for Muir-Torre syndrome. In this cohort, IHC analysis, MSI status and genetic testing were in agreement, showing eight MSH2 and two MLH1 germline mutations. Five patients were immunosuppressed and their sebaceous tumors showed a lack of MSH2/MSH6 expression, although just one case with positive family history for visceral cancer harbored a germline mutation. In immunosuppressed patients, loss of IHC for MMR proteins is not necessarily secondary to MMR germline mutations. IHC false positives are probably due to epigenetic alterations. MSI and lack of expression of MMR proteins can be recognized also in immunocompromised patients without MMR germline mutations. PMID:24969397

Ponti, G; Pellacani, G; Ruini, C; Percesepe, A; Longo, C; Mandel, V Desmond; Crucianelli, F; Gorelli, G; Tomasi, A

2014-12-01

123

FDTD-ANT User Manual  

NASA Technical Reports Server (NTRS)

This manual explains the theory and operation of the finite-difference time domain code FDTD-ANT developed by Analex Corporation at the NASA Lewis Research Center in Cleveland, Ohio. This code can be used for solving electromagnetic problems that are electrically small or medium (on the order of 1 to 50 cubic wavelengths). Calculated parameters include transmission line impedance, relative effective permittivity, antenna input impedance, and far-field patterns in both the time and frequency domains. The maximum problem size may be adjusted according to the computer used. This code has been run on the DEC VAX and 486 PC's and on workstations such as the Sun Sparc and the IBM RS/6000.

Zimmerman, Martin L.

1995-01-01

124

Fault-Tolerant ANTS Tobias Langner, Jara Uitto, David Stolz, and Roger Wattenhofer  

E-print Network

Fault-Tolerant ANTS Tobias Langner, Jara Uitto, David Stolz, and Roger Wattenhofer ETH Z¨urich, Switzerland Abstract. In this paper, we study a variant of the Ants Nearby Treasure Search problem, where n number of failures. 1 Introduction Ant colonies are a prime example of biological systems that are fault

125

Abundance of -1,6-piperideine alkaloids in imported fire ants  

Technology Transfer Automated Retrieval System (TEKTRAN)

Workers of imported fire ants, including red imported fire ants, Solenopsis invicta Buren, black imported fire ants, S. richteri Forel, and their hybrid (S. invicta × S. richteri), are vicious stingers. Since the venomous sting is a significant medical problem to humans, the chemistry of imported f...

126

Universality in ant behaviour.  

PubMed

Prediction for social systems is a major challenge. Universality at the social level has inspired a unified theory for urban living but individual variation makes predicting relationships within societies difficult. Here, we show that in ant societies individual average speed is higher when event duration is longer. Expressed as a single scaling function, this relationship is universal because for any event duration an ant, on average, moves at the corresponding average speed except for a short acceleration and deceleration at the beginning and end. This establishes cause and effect within a social system and may inform engineering and control of artificial ones. PMID:25411406

Christensen, Kim; Papavassiliou, Dario; de Figueiredo, Alexandre; Franks, Nigel R; Sendova-Franks, Ana B

2015-01-01

127

Universality in ant behaviour  

PubMed Central

Prediction for social systems is a major challenge. Universality at the social level has inspired a unified theory for urban living but individual variation makes predicting relationships within societies difficult. Here, we show that in ant societies individual average speed is higher when event duration is longer. Expressed as a single scaling function, this relationship is universal because for any event duration an ant, on average, moves at the corresponding average speed except for a short acceleration and deceleration at the beginning and end. This establishes cause and effect within a social system and may inform engineering and control of artificial ones. PMID:25411406

Christensen, Kim; Papavassiliou, Dario; de Figueiredo, Alexandre; Franks, Nigel R.; Sendova-Franks, Ana B.

2015-01-01

128

Ant Colony Optimization  

Microsoft Academic Search

ABSTRACT IN THIS PAPER, WE STUDY THE RELATIONSHIP BETWEEN THE TWO TECHNIQUES KNOWN AS ANT COLONY OPTIMIZATION (ACO) AND STOCHASTIC GRADIENT DESCENT. MORE PRECISELY, WE SHOW THAT SOME EMPIRICAL ACO ALGORITHMS APPROXIMATE STOCHASTIC GRADIENT DESCENT IN THE SPACE OF PHEROMONES, AND WE PROPOSE AN IMPLEMENTATION OF STOCHASTIC GRADIENT DESCENT THAT BELONGS TO THE FAM-ILY OF ACO ALGORITHMS. WE THEN USE

Marco Dorigo; Mauro Birattari

2010-01-01

129

Tiny, Powerful, Awesome Ants!  

ERIC Educational Resources Information Center

Peering through a thematic science lens--elementary students embarked on a one-week study of ants during a month-long summer school program. This integrated unit addressed reading and writing skills while developing the science-process skills of observation, inferring, and communicating in a motivating and authentic way. Pre- and post-assessments…

Tate, Kathleen

2007-01-01

130

Ants, Rationality, and Recruitment  

Microsoft Academic Search

This paper offers an explanation of behavior that puzzled entomologists and economists. Ants, faced with two identical food sources, were observed to concentrate more on one of these but, after a period, they would turn their attention to the other. The same phenomenon has been observed in humans choosing between restaurants. After discussing the nature of foraging and recruitment behavior

Alan Kirman

1993-01-01

131

Ant Hill in Pantanal  

USGS Multimedia Gallery

Ant hill with flowers in Copernicia alba palm savannah near the Rio Negro river. Yellow flowers are 2 species of Asteraceae, blue flowers are a Commelina spp. Located near RAMSAR site and Rio Negro National Park in the Pantanal ecoregion, near the border between Paraguay and Bolivia. This region, si...

132

The Fuzzy Ant  

Microsoft Academic Search

We apply fuzzy modeling to transform a verbal description of the foraging behavior of ants into a well-defined mathematical model. The resulting model is simpler, more plausible, and more amenable to analysis than previously suggested models. We believe that fuzzy modeling may be suitable for addressing biomimicry, that is, the development of artificial products or machines that mimic biological phenomena,

Valeri Rozin; Michael Margaliot

2007-01-01

133

Face to Face with Ants  

NSDL National Science Digital Library

Imagine being the size of an ant. Be careful - a face-to-face encounter with an ant would be scary and potentially life-threatening! But, if you avoided being eaten, you could learn a lot about ant anatomy from a close-up view. Ants have many body parts that are normally hard to see without a magnifying glass or microscope. And each structure has its own special function.

Dr. Biology

134

An improved ant colony algorithm with diversified solutions based on the immune strategy  

PubMed Central

Background Ant colony algorithm has emerged recently as a new meta-heuristic method, which is inspired from the behaviours of real ants for solving NP-hard problems. However, the classical ant colony algorithm also has its defects of stagnation and premature. This paper aims at remedying these problems. Results In this paper, we propose an adaptive ant colony algorithm that simulates the behaviour of biological immune system. The solutions of the problem are much more diversified than traditional ant colony algorithms. Conclusion The proposed method for improving the performance of traditional ant colony algorithm takes into account the polarization of the colonies, and adaptively adjusts the distribution of the solutions obtained by the ants. This makes the solutions more diverse so as to avoid the stagnation and premature phenomena. PMID:17217521

Qin, Ling; Pan, Yi; Chen, Ling; Chen, Yixin

2006-01-01

135

Ant Algorithms for Discrete Optimization  

E-print Network

Ant Algorithms for Discrete Optimization Marco Dorigo Gianni Di Caro IRIDIA CP 194/6 Universit@iridia.ulb.ac.be Luca M. Gambardella IDSIA Corso Elvezia 36 CH-6900 Lugano Switzerland luca@idsia.ch Keywords ant algorithms, ant colony optimiza- tion, swarm intelligence, metaheuris- tics, natural computation Abstract

Hutter, Frank

136

Ant Algorithms for Discrete Optimization  

E-print Network

Ant Algorithms for Discrete Optimization Marco Dorigo and Gianni Di Caro IRIDIA, Universit#19;e, Switzerland luca@idsia.ch Abstract This paper overviews recent work on ant algorithms, that is, algorithms for discrete optimization which took inspiration from the observation of ant colonies foraging behavior

Ducatelle, Frederick

137

Ant Algorithms for Discrete Optimization  

E-print Network

Ant Algorithms for Discrete Optimization Marco Dorigo and Gianni Di Caro IRIDIA, Universit´e Libre, Switzerland luca@idsia.ch Abstract This paper overviews recent work on ant algorithms, that is, algorithms for discrete optimization which took inspiration from the observation of ant colonies foraging behavior

Gambardella, Luca Maria

138

Bees_ Ants Based Routing Algorithm  

Microsoft Academic Search

In this paper we propose a novel routing algorithm called Bees_Ants algorithm. This algorithm is a combination of ant colony based routing algorithm (ARA) and BeeHive based routing algorithm. The proposed routing algorithm depends on splitting the network into two parts; one is a fixed network and the other is a mobile ad hoc network (MANET), then applying the ant

Eslam Al Maghayreh; Salam Abu Al-Haija; Faisal Alkhateeb; Shadi Aljawarneh

2010-01-01

139

Muir-Torre Syndrome  

MedlinePLUS

... your doctor: What is my risk of developing colorectal cancer? What is my risk of developing skin cancer? What is my risk ... following questions: Does my family history increase my risk of colorectal cancer? Does my family history increase my risk of ...

140

Ant-Based Cyber Security  

SciTech Connect

We describe a swarming-agent-based, mixed-initiative approach to infrastructure defense where teams of humans and software agents defend cooperating organizations in tandem by sharing insights and solutions without violating proprietary boundaries. The system places human administrators at the appropriate level where they provide system guidance while lower-level agents carry out tasks humans are unable to perform quickly enough to mitigate today’s security threats. Cooperative Infrastructure Defense (CID) uses our ant-based approach to enable dialogue between humans and agents to foster a collaborative problem-solving environment, increase human situational awareness and influence using visualization and shared control. We discuss theoretical implementation characteristics along with results from recent proof-of-concept implementations.

Haack, Jereme N.; Fink, Glenn A.; Maiden, Wendy M.; McKinnon, Archibald D.; Templeton, Steven J.; Fulp, Errin W.

2011-07-12

141

Solving Symmetric and Asymmetric TSPs by Ant Colonies  

Microsoft Academic Search

In this paper we present ACS, a distributed algorithm for the solution of combinatorial optimization problems which was inspired by the observation of real colonies of ants. We apply ACS to both symmetric and asymmetric traveling salesman problems. Results show that ACS is able to find good solutions to these problems.

Luca Maria Gambardella; Marco Dorigo

1996-01-01

142

Chaos–order transition in foraging behavior of ants  

PubMed Central

The study of the foraging behavior of group animals (especially ants) is of practical ecological importance, but it also contributes to the development of widely applicable optimization problem-solving techniques. Biologists have discovered that single ants exhibit low-dimensional deterministic-chaotic activities. However, the influences of the nest, ants’ physical abilities, and ants’ knowledge (or experience) on foraging behavior have received relatively little attention in studies of the collective behavior of ants. This paper provides new insights into basic mechanisms of effective foraging for social insects or group animals that have a home. We propose that the whole foraging process of ants is controlled by three successive strategies: hunting, homing, and path building. A mathematical model is developed to study this complex scheme. We show that the transition from chaotic to periodic regimes observed in our model results from an optimization scheme for group animals with a home. According to our investigation, the behavior of such insects is not represented by random but rather deterministic walks (as generated by deterministic dynamical systems, e.g., by maps) in a random environment: the animals use their intelligence and experience to guide them. The more knowledge an ant has, the higher its foraging efficiency is. When young insects join the collective to forage with old and middle-aged ants, it benefits the whole colony in the long run. The resulting strategy can even be optimal. PMID:24912159

Li, Lixiang; Peng, Haipeng; Kurths, Jürgen; Yang, Yixian; Schellnhuber, Hans Joachim

2014-01-01

143

The hyper-cube framework for ant colony optimization.  

PubMed

Ant colony optimization is a metaheuristic approach belonging to the class of model-based search algorithms. In this paper, we propose a new framework for implementing ant colony optimization algorithms called the hyper-cube framework for ant colony optimization. In contrast to the usual way of implementing ant colony optimization algorithms, this framework limits the pheromone values to the interval [0,1]. This is obtained by introducing changes in the pheromone value update rule. These changes can in general be applied to any pheromone value update rule used in ant colony optimization. We discuss the benefits coming with this new framework. The benefits are twofold. On the theoretical side, the new framework allows us to prove that in Ant System, the ancestor of all ant colony optimization algorithms, the average quality of the solutions produced increases in expectation over time when applied to unconstrained problems. On the practical side, the new framework automatically handles the scaling of the objective function values. We experimentally show that this leads on average to a more robust behavior of ant colony optimization algorithms. PMID:15376861

Blum, Christian; Dorigo, Marco

2004-04-01

144

Exploitation and interference competition between the invasive Argentine ant, Linepithema humile , and native ant species  

Microsoft Academic Search

Interactions between the invasive Argentine ant, Linepithema humile, and native ant species were studied in a 450-ha biological reserve in northern California. Along the edges of the invasion, the presence of Argentine ants significantly reduced the foraging success of native ant species, and vice versa. Argentine ants were consistently better than native ants at exploiting food sources: Argentine ants found

Kathleen G. Human; Deborah M. Gordon

1996-01-01

145

Ant Routing Simulation B.A. Bagula, H.A.C. de Villiers, J. du Toit, A.E. Krzesinski, M. Loubser, J.G. van der Horst  

E-print Network

Ant Routing Simulation B.A. Bagula, H.A.C. de Villiers, J. du Toit, A.E. Krzesinski, M. Loubser, J of foraging ants to network routing problems has received much attention. The distributed nature of ant algorithms in modern telecommunication networks. In this paper we present a simulation of an ant routing

Geldenhuys, Jaco

146

The urban fire ant paradox: native fire ants persist in an urban refuge while invasive fire ants dominate natural habitats  

Microsoft Academic Search

In contrast to the widespread extirpation of native fire ants (Solenopsis geminata) across southern US following the invasion by imported red fire ants (S. invicta), some residential areas of Austin form unexpected refuges for native fire ants. Ironically, these urban environments provide\\u000a refuges for the native fire ants while adjacent natural habitats have been overrun by invasive fire ants. Resistance

Robert M. Plowes; John G. Dunn; Lawrence E. Gilbert

2007-01-01

147

Ant algorithms for discrete optimization.  

PubMed

This article presents an overview of recent work on ant algorithms, that is, algorithms for discrete optimization that took inspiration from the observation of ant colonies' foraging behavior, and introduces the ant colony optimization (ACO) metaheuristic. In the first part of the article the basic biological findings on real ants are reviewed and their artificial counterparts as well as the ACO metaheuristic are defined. In the second part of the article a number of applications of ACO algorithms to combinatorial optimization and routing in communications networks are described. We conclude with a discussion of related work and of some of the most important aspects of the ACO metaheuristic. PMID:10633574

Dorigo, M; Di Caro, G; Gambardella, L M

1999-01-01

148

Application of ant colony optimization to optimal foragaing theory: comparison of simulation and field results  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ant Colony Optimization (ACO) refers to the family of algorithms inspired by the behavior of real ants and used to solve combinatorial problems such as the Traveling Salesman Problem (TSP).Optimal Foraging Theory (OFT) is an evolutionary principle wherein foraging organisms or insect parasites seek ...

149

Automated selection of appropriate pheromone representations in ant colony optimization.  

PubMed

Ant colony optimization (ACO) is a constructive metaheuristic that uses an analogue of ant trail pheromones to learn about good features of solutions. Critically, the pheromone representation for a particular problem is usually chosen intuitively rather than by following any systematic process. In some representations, distinct solutions appear multiple times, increasing the effective size of the search space and potentially misleading ants as to the true learned value of those solutions. In this article, we present a novel system for automatically generating appropriate pheromone representations, based on the characteristics of the problem model that ensures unique pheromone representation of solutions. This is the first stage in the development of a generalized ACO system that could be applied to a wide range of problems with little or no modification. However, the system we propose may be used in the development of any problem-specific ACO algorithm. PMID:16053571

Montgomery, James; Randall, Marcus; Hendtlass, Tim

2005-01-01

150

Ants, Crickets and Frogs in Cyclic Pursuit  

E-print Network

Ants, Crickets and Frogs in Cyclic Pursuit A.M. Bruckstein 1 , N. Cohen 2 , A. Efrat 1 Abstract. We consider a deterministic continuous pursuit, in which n ants chase each other in cyclic order Imagine n ants in the plane, searching for food. The leading ant determines the course; the second ant

Efrat, Alon

151

USING ANT COMMUNITIES FOR RAPID ASSESSMENT OF TERRESTRIAL ECOSYSTEM HEALTH  

SciTech Connect

Ecosystem health with its near infinite number of variables is difficult to measure, and there are many opinions as to which variables are most important, most easily measured, and most robust, Bioassessment avoids the controversy of choosing which physical and chemical parameters to measure because it uses responses of a community of organisms that integrate all aspects of the system in question. A variety of bioassessment methods have been successfully applied to aquatic ecosystems using fish and macroinvertebrate communities. Terrestrial biotic index methods are less developed than those for aquatic systems and we are seeking to address this problem here. This study had as its objective to examine the baseline differences in ant communities at different seral stages from clear cut back to mature pine plantation as a precursor to developing a bioassessment protocol. Comparative sampling was conducted at four seral stages; clearcut, 5 year, 15 year and mature pine plantation stands. Soil and vegetation data were collected at each site. All ants collected were preserved in 70% ethyl alcohol and identified to genus. Analysis of the ant data indicates that ants respond strongly to the habitat changes that accompany ecological succession in managed pine forests and that individual genera as well as ant community structure can be used as an indicator of successional change. Ants exhibited relatively high diversity in both early and mature seral stages. High ant diversity in the mature seral stages was likely related to conditions on the forest floor which favored litter dwelling and cool climate specialists.

Wike, L; Doug Martin, D; Michael Paller, M; Eric Nelson, E

2007-01-12

152

A Graph-based Ant System and its convergence  

Microsoft Academic Search

A general framework for solving combinatorial optimization problems heuristically by the Ant System approach is developed. The framework is based on the concept of a construction graph, a graph assigned to an instance of the optimization problem under consideration, encoding feasible solutions by walks. It is shown that under certain conditions, the solutions generated in each iteration of this Graph{based

Walter J. Gutjahr

2000-01-01

153

Temperature: Human Regulating, Ants Conforming  

ERIC Educational Resources Information Center

Biological processes speed up as temperature rises. Procedures for demonstrating this with ants traveling on trails, and data gathered by students on the Argentine ant ("Linepithema humile") are presented. The concepts of temperature regulation and conformity are detailed with a focus on the processes rather than on terms that label the organisms.

Clopton, Joe R.

2007-01-01

154

California Academy of Sciences: AntWeb  

NSDL National Science Digital Library

AntWeb, an excellent service of the California Academy of Sciences, provides users with "tools for exploring the diversity and identification of ants (Hymenoptera: Formicidae). These tools have been developed to facilitate the use of ants in inventory and monitoring programs and provide ant taxonomists with images and types." At present, AntWeb offers information on all ant genera worldwide as well as highlighting ants of Madagascar and California in particular. The site provides a search engine for the comprehensive AntWeb database which contains images of, and information about, ants from all over the world. AntWeb also offers an awesome World Ants Slide Show which includes Head, Profile, and Dorsal Views of many ants.

155

College of Arts and Sciences ANT Anthropology  

E-print Network

College of Arts and Sciences ANT Anthropology KEY: # = new course * = course changed =coursedropped University of Kentucky 2013-2014 Undergraduate Bulletin 1 ANT 101 INTRODUCTION TO ANTHROPOLOGY. (3 the instructor has worked. ANT 220 INTRODUCTION TO CULTURAL ANTHROPOLOGY. (3

MacAdam, Keith

156

Three-dimensional ant  

NSDL National Science Digital Library

Three-dimensional rendering of an ant. This movie is also available as a Virtual Reality Modeling Language (VRML) model. The VRML models are more interactive than the QuickTime versions, but special software may need to be downloaded to open them (read the ÃÂHelpÃÂ page for details). Those people using public computers may be limited from fully accessing the resource. Mozilla Firefox users can view the VRML files directly in their browsers by downloading the Cortona extension (http://www.parallelgraphics.com/products/cortona/download/netscape/). This website is an excellent educational resource for all ages. The Virtual Insects home page (http://www.ento.vt.edu/~sharov/3d/3dinsect.html) has a basic explanation of how virtual reality works, including the Virtual Reality Modeling Language. The "Virtual Images" link takes you to a list of insects that can be viewed as 3D digital reconstructions. The image files would make excellent additions to teaching lectures for introductory classes. Visit the "How to Build Virtual Insects" page to read about how the images were created and how the orginal models were made more biologically accurate. Also be sure to read the page on how to view the cyber-insects inside a virtual reality "cave".

0002-11-30

157

INVASIVE ANTS Invasive species, those species that demonstrate  

E-print Network

PART IV INVASIVE ANTS Invasive species, those species that demonstrate ecological, environmental own right. Though invasive ants currently comprise ant species, the contribution of these species to understanding ant ecology is dis- proportional to their number. Invasive ants represent

Suarez, Andrew V.

158

Ants in Parking Lots Arnold L. Rosenberg  

E-print Network

Ants in Parking Lots Arnold L. Rosenberg Electrical & Computer Engineering Colorado State University Fort Collins, CO 80523, USA rsnbrg@colostate.edu Abstract Ants provide an attractive metaphor of ant-based computation models. We study the ability of ant-robots that are essentially mobile finite

Massachusetts at Amherst, University of

159

Ant Foraging Revisited Liviu Alexandru Panait1  

E-print Network

Ant Foraging Revisited Liviu Alexandru Panait1 and Sean Luke1 1. Department of Computer Science: lpanait@cs.gmu.edu Abstract Previous artificial (non-biological) ant foraging models have to date relied ants with the knowledge of the nest direction. In contrast, the work presented solves ant foraging

Luke, Sean

160

Cooperative transport by ants and robots  

Microsoft Academic Search

In several species of ants, workers cooperate to retrieve large prey. Usually, one ant finds a prey item, tries to move it, and when unsuccessful for some time, recruits nestmates through direct contact or chemical marking. When a group of ants tries to move large prey, the ants change position and alignment until the prey can be moved toward the

C. Ronald Kube; Eric Bonabeau

2000-01-01

161

Improvements on Ant-System: Introducing MAX-MIN Ant System  

Microsoft Academic Search

Ant System is a general purpose heuristic algorithm inspired by the foraging behavior ofreal ant colonies. Here we introduce an improved version of Ant System, that we called MAX --MIN Ant System. We describe the new features present in MAX --MIN Ant System, makea detailed experimental investigation on the contribution of the design choices to the improvedperformance and give computational

Thomas Stützle; Holger Hoos

1996-01-01

162

Ants and Their Control There are many species of ants in Maryland but only a few  

E-print Network

1 Ants and Their Control There are many species of ants in Maryland but only a few are pests in the home. Two species of ants may require special attention because of their behavior. Carpenter ants can cause structural damage. They are covered in the Entomology leaflet #115 on Carpenter Ants

Hill, Wendell T.

163

Behavioral interactions of the invasive Argentine ant with native ant species  

Microsoft Academic Search

Summary: The Argentine ant, Linepithema humile, has invaded many areas of the world, displacing native ants. Its behavior may contribute to its competitive success. Staged and natural encounters were observed at food resources in the field, between Argentine ants and eight ant species native to northern California. There was no relation between the frequency of aggression by any ant species

K. G. Human; D. M. Gordon

1999-01-01

164

Ant Colony Approach to Predict Amino Acid Interaction Networks Le Havre University  

E-print Network

Ant Colony Approach to Predict Amino Acid Interaction Networks Omar GACI Le Havre University LITIS the notion of protein interaction network. This is a graph whose vertices are the proteins amino acids's interaction network from its amino acid sequence. An ant colony approach is used to solve this problem. 1

Boyer, Edmond

165

Scheduling Continuous Casting of Aluminum Using a Multiple-Objective Ant Colony Optimization Metaheuristic  

Microsoft Academic Search

This paper presents an ant colony optimizationmetaheuristic for the solution of an industrialscheduling problem in an aluminum castingcenter. We present an efficient representation of acontinuous horizontal casting process which takesaccount of a number of objectives that areimportant to the scheduler. We have incorporatedthe methods proposed in software that has beenimplemented in the plant.Keywords: scheduling, metaheuristic, ant colonyoptimization, aluminum, casting,...

Marc Gravel; Wilson L. Price

2001-01-01

166

Dynamic Optimization of Chemical Processes using Ant Colony Framework  

Microsoft Academic Search

Ant colony framework is illustrated by considering dynamic optimization of six important bench marking examples. This new computational tool is simple to implement and can tackle problems with state as well as terminal constraints in a straightforward fashion. It requires fewer grid points to reach the global optimum at relatively very low computational effort. The examples with varying degree of

J. Rajesh; Kapil Gupta; Hari Shankar Kusumakar; Vaidyanathan K. Jayaraman; Bhaskar D. Kulkarni

2001-01-01

167

Reconstructing Amino Acid Interaction Networks by an Ant Colony Approach  

E-print Network

Reconstructing Amino Acid Interaction Networks by an Ant Colony Approach Omar GACI and Stefan BALEV are the proteins amino acids and whose edges are the interactions between them. We consider the problem of reconstructing protein's interaction network from its amino acid sequence. We rely on a probability that two

Paris-Sud XI, Université de

168

How Ants Drop Out: Ant Abundance on Tropical Mountains  

PubMed Central

In tropical wet forests, ants are a large proportion of the animal biomass, but the factors determining abundance are not well understood. We characterized ant abundance in the litter layer of 41 mature wet forest sites spread throughout Central America (Chiapas, Guatemala, Honduras, Nicaragua, and Costa Rica) and examined the impact of elevation (as a proxy for temperature) and community species richness. Sites were intentionally chosen to minimize variation in precipitation and seasonality. From sea level to 1500 m ant abundance very gradually declined, community richness declined more rapidly than abundance, and the local frequency of the locally most common species increased. These results suggest that within this elevational zone, density compensation is acting, maintaining high ant abundance as richness declines. In contrast, in sites above 1500 m, ant abundance dropped abruptly to much lower levels. Among these high montane sites, community richness explained much more of the variation in abundance than elevation, and there was no evidence of density compensation. The relative stability of abundance below 1500 m may be caused by opposing effects of temperature on productivity and metabolism. Lower temperatures may decrease productivity and thus the amount of food available for consumers, but slower metabolisms of consumers may allow maintenance of higher biomass at lower resource supply rates. Ant communities at these lower elevations may be highly interactive, the result of continuous habitat presence over geological time. High montane sites may be ephemeral in geological time, resulting in non-interactive communities dominated by historical and stochastic processes. Abundance in these sites may be determined by the number of species that manage to colonize and/or avoid extinction on mountaintops. PMID:25098722

Longino, John T.; Branstetter, Michael G.; Colwell, Robert K.

2014-01-01

169

Memory Analysis and Significance Test for Agent University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom  

E-print Network

: Artificial ant trails (a) John Muir trail (b) Santa Fe trail (*: ant agent, : food) The artificial ant the food on the trails. The first work, by Jef- ferson et al. [7], used the John Muir trail, and another in the John Muir trail with two different con- troller schemes, finite state machines and recurrent neural

Fernandez, Thomas

170

NOVA: Lord of the Ants  

NSDL National Science Digital Library

As a young man growing up in Depression-era Alabama, E.O.Wilson spent a great time outdoors observing everything from butterflies to ants. His fascination with ants grew into a lifelong passion, and amidst his many accomplishments in later life, he would win a Pulitzer Prize for his 1991 work "The Ants". Today Wilson continues to be well-known as a strong advocate for the protection of the environment and his work in the field of sociobiology. Wilson was recently profiled in an episode of the popular PBS program "NOVA, and this site allows visitors to watch the program in its entirety as well as view a transcript or purchase a DVD of the program.

2008-05-20

171

8.EE Ant and Elephant  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: An ant has a mass of approximately $4 \\times 10^{?3}$ grams and an elephant has a mass of approximately 8 metric tons. How many ants does it take to ha...

172

Do aphids actively search for ant partners?  

PubMed

The aphid-ant mutualistic relationships are not necessarily obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is largely assumed that ants actively search for their mutualistic partners namely using volatile cues; whether winged aphids (i.e., aphids' most mobile form) are able to select ant-frequented areas had not been investigated so far. Ant-frequented sites would indeed offer several advantages for these aphids including a lower predation pressure through ant presence and enhanced chances of establishing mutuaslistic interactions with neighbor ant colonies. In the field, aphid colonies are often observed in higher densities around ant nests, which is probably linked to a better survival ensured by ants' services. Nevertheless, this could also result from a preferential establishment of winged aphids in ant-frequented areas. We tested this last hypothesis through different ethological assays and show that the facultative myrmecophilous black bean aphid, Aphis fabae L., does not orientate its search for a host plant preferentially toward ant-frequented plants. However, our results suggest that ants reduce the number of winged aphids leaving the newly colonized plant. Thus, ants involved in facultative myrmecophilous interactions with aphids appear to contribute to structure aphid populations in the field by ensuring a better establishment and survival of newly established colonies rather than by inducing a deliberate plant selection by aphid partners based on the proximity of ant colonies. PMID:24659520

Fischer, Christophe Y; Vanderplanck, Maryse; Lognay, Georges C; Detrain, Claire; Verheggen, François J

2014-03-21

173

FORMIS: A Master Bibliography of Ant Literature  

NSDL National Science Digital Library

FORMIS is a composite of several ant literature databases. It contains citations for a large fraction of the world's ant literature (about 38,000 references). FORMIS contains all known ant taxonomic literature (through 1996). It also contains comprehensive bibliographies of leaf-cutting ants, fire ants, and Russian wood ants. FORMIS is also the only database which covers ant literature before the 1970s. For further details please see contributions and credits. This database is designed to allow convenient searches of titles, keywords and abstracts when available (online searches or downloads). Citations from this database can be exported to create specialty databases or personal reprint indexes. FORMIS is only updated every year or two, so it is not a source for the most recent ant literature.

0000-00-00

174

Hey! A Fire Ant Stung Me!  

MedlinePLUS

... Main Page The Pink Locker Society Hey! A Fire Ant Stung Me! KidsHealth > Kids > Illnesses & Injuries > Bug ... Do How to Avoid Getting Bitten What's a Fire Ant? There are many different types of fire ...

175

Ant Hill Near Tebicuary River  

USGS Multimedia Gallery

Ant hill near grassland-forest ecotone near Tebicuary river. This former pasture has not been grazed since an endangered bird species was discovered here half a dozen years ago. The Ñeembucú Region is typified by extensive grasslands and wetlands. Near 26°34’52’’S...

176

Ant Ecdysteroid Extraction and Radioimmunoassay  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ecdysteroids are a group of steroid compounds present in many plant and invertebrate species. In arthropods, they function primarily as hormones involved in the regulation of molting. This protocol describes how to extract ecdysteroid hormones from ant specimens and subsequently quantify circulating...

177

ANTBIRDS PARASITIZE FORAGING ARMY ANTS  

Microsoft Academic Search

In the tropical forests of Central and South America, army ants of the Eci- tonini tribe, and the numerous animals that follow them through the understory, share a complex relationship that has far-reaching effects on population dynamics and community structure. Although considerable study has been made of various participants in this re- lationship, no research has explicitly examined the nature

Peter H. Wrege; Martin Wikelski; James T. Mandel; Thomas Rassweiler; Iain D. Couzin

2005-01-01

178

Ants are among the most prevalent pests in households. Ants also invade restau-  

E-print Network

Ants are among the most prevalent pests in households. Ants also invade restau- rants, hospitals indoor plants, ants protect and care for honeydew-producing insects such as aphids, soft scales, whiteflies, and mealy- bugs, increasing damage from these pests. Ants also perform many useful functions

Ishida, Yuko

179

Red Imported Fire Ant Biology Red imported fire ants live in colonies that contain  

E-print Network

Red Imported Fire Ant Biology Red imported fire ants live in colonies that contain cream-colored to white immature ants, often called brood. The brood is comprised of the eggs, larvae, and pupae. Also within the colonies are adult ants of different types, or castes. The castes include winged males, winged

Balasundaram, Balabhaskar "Baski"

180

Using Ants to Investigate the Environment  

ERIC Educational Resources Information Center

The best place for students to begin to understand complex environmental relationships is in their own back yards. Doing investigations of ants allows students to establish a baseline survey of ant fauna, test the importance of ants in nutrient cycling and soil structure maintenance, and increase their understanding of the environment and their…

Hagevik, Rita A.

2005-01-01

181

Using Ants To Investigate the Environment.  

ERIC Educational Resources Information Center

Describes three inquiry-based activities designed for students to begin to understand complex environmental relationships in their own backyard. Includes investigations of ants, which allow students to establish a baseline survey of ant fauna, test the importance of ants in nutrient cycling and soil structure maintenances, and increase student…

Hagevik, Rita A.

2003-01-01

182

Ant Colony Optimization for Constraint Satisfaction  

E-print Network

Ant Colony Optimization for Constraint Satisfaction Christine Solnon LIRIS, UMR 5205 CNRS / University of Lyon Tutorial at CP'2007 #12;Ant Colony Optimization Application to car sequencing Application to CSPs Conclusion Table of contents 1 Basic principles of Ant Colony Optimization 2 Application

Solnon, Christine

183

Interactions between Ants and Pine Weevils  

E-print Network

Interactions between Ants and Pine Weevils Effects on Forest Regeneration Subtitle (if any-91-576-8157-7 © 2014 Vítzslav Maák, Uppsala Print: SLU Service/Repro, Uppsala 2014 Cover: Red wood ant and pine weevil. Artwork by Henrik Nordenhem (photo: V. Maák) #12;Interactions between Ants and Pine Weevils: Effects

184

FIRE ANT, BIOLOGY, ECOLOGY, AND BIOCONTROL  

Technology Transfer Automated Retrieval System (TEKTRAN)

The red fire ant Solenopsis invicta was accidentally introduced into the United States from South America sometime in the 1930s. These ants do best in open, disturbed habitats associated with human activities. Fire ants construct large earthen mounds which function as solar collecting devises. Fire...

185

Biological control of red imported fire ants  

Technology Transfer Automated Retrieval System (TEKTRAN)

Two species of Imported Fire Ants (IFA), the Red Imported Fire Ant, Solenopsis invicta Buren, and the Black Imported Fire Ant, S. richteri Forel, were introduced into the United States in the early 1900s and currently inhabit over 320 million acres in the southern United States and Puerto Rico. Red ...

186

The Ant Colony Optimization Metaheuristic: Algorithms, Applications, and Advances  

Microsoft Academic Search

The field of ACO algorithms is very lively, as testified, for example, by the successful biannual workshop (ANTS—From Ant Colonies to Artificial Ants: A Series of International Workshops on Ant Algorithms; http:\\/\\/iridia.ulb.ac.be\\/~ants\\/) where researchers meet to discuss the properties of ACO and other ant algorithms, both theoretically and experimentally.

Marco Dorigo; Thomas Stützle

187

ANTS VI: algorithmic number theory symposium poster abstracts  

Microsoft Academic Search

The Algorithmic Number Theory Symposium (ANTS) meetings are held bianually since 1994, and have become the premier international forum for the presentation of new research in Computational Number Theory. Previous ANTS conferences have been held as follows: ANTS I, 1994, Cornell University, USA, ANTS II, 1996, University of Bordeaux, France, ANTS III, 1998 Reed College, USA, ANTS IV, 2000, University

Ilias Kotsireas; Emil Volcheck

2004-01-01

188

Mineralogy, petrology and chemistry of ANT-suite rocks from the lunar highlands  

NASA Technical Reports Server (NTRS)

Anorthositic-noritic-troctolitic (ANT) rocks are the oldest and most abundant rocks of the lunar surface, and comprise about 90% of the suite of the lunar highlands. Consideration is given to the mineralogy, petrology, bulk chemistry, and origin of ANT-suite rocks. Problems associated in classifying and labeling lunar highland rocks because of textural complexities occurring from impact modifications are discussed. The mineralogy of ANT-suite rocks, dominated by plagioclase, olivine and pyrozene, and containing various minor minerals, is outlined. The petrology of ANT-suite rocks is reviewed along with the major element bulk composition of these rocks, noting that they are extremely depleted in K2O and P2O5. Various models describing the origin of ANT-suite rocks are summarized, and it is suggested that this origin involves a parental liquid of high-alumina basalt with low Fe/Fe+Mg.

Prinz, M.; Keil, K.

1977-01-01

189

A Hybrid Routing Algorithm Based on Ant Colony and ZHLS Routing Protocol for MANET  

NASA Astrophysics Data System (ADS)

Mobile Ad hoc networks (MANETs) require dynamic routing schemes for adequate performance. This paper, presents a new routing algorithm for MANETs, which combines the idea of ant colony optimization with Zone-based Hierarchical Link State (ZHLS) protocol. Ant colony optimization (ACO) is a class of Swarm Intelligence (SI) algorithms. SI is the local interaction of many simple agents to achieve a global goal. SI is based on social insect for solving different types of problems. ACO algorithm uses mobile agents called ants to explore network. Ants help to find paths between two nodes in the network. Our algorithm is based on ants jump from one zone to the next zones which contains of the proactive routing within a zone and reactive routing between the zones. Our proposed algorithm improves the performance of the network such as delay, packet delivery ratio and overhead than traditional routing algorithms.

Rafsanjani, Marjan Kuchaki; Asadinia, Sanaz; Pakzad, Farzaneh

190

Methods for Casting Subterranean Ant Nests  

PubMed Central

The study of subterranean ant nests has been impeded by the difficulty of rendering their structures in visible form. Here, several different casting materials are shown to make perfect casts of the underground nests of ants. Each material (dental plaster, paraffin wax, aluminum, zinc) has advantages and limitations, which are discussed. Some of the materials allow the recovery of the ants entombed in the casts, allowing a census of the ants to be connected with features of their nest architecture. The necessary equipment and procedures are described in the hope that more researchers will study this very important aspect of ant natural history. PMID:20673073

Tschinkel, Walter R.

2010-01-01

191

Team swimming in ant spermatozoa.  

PubMed

In species where females mate promiscuously, competition between ejaculates from different males to fertilize the ova is an important selective force shaping many aspects of male reproductive traits, such as sperm number, sperm length and sperm-sperm interactions. In eusocial Hymenoptera (bees, wasps and ants), males die shortly after mating and their reproductive success is ultimately limited by the amount of sperm stored in the queen's spermatheca. Multiple mating by queens is expected to impose intense selective pressure on males to optimize the transfer of sperm to the storage organ. Here, we report a remarkable case of cooperation between spermatozoa in the desert ant Cataglyphis savignyi. Males ejaculate bundles of 50-100 spermatozoa. Sperm bundles swim on average 51% faster than solitary sperm cells. Team swimming is expected to increase the amount of sperm stored in the queen spermatheca and, ultimately, enhance male posthumous fitness. PMID:24919705

Pearcy, Morgan; Delescaille, Noémie; Lybaert, Pascale; Aron, Serge

2014-06-01

192

Revolutionizing Remote Exploration with ANTS  

NASA Astrophysics Data System (ADS)

We are developing the Autonomous Nano-Technology Swarm (ANTS) architecture based on an insect colony analogue for the cost-effective, efficient, systematic survey of remote or inaccessible areas with multiple object targets, including planetary surface, marine, airborne, and space environments. The mission context is the exploration in the 2020s of the most compelling remaining targets in the solar system: main belt asteroids. Main belt asteroids harbor important clues to Solar System origins and evolution which are central to NASA's goals in Space Science. Asteroids are smaller than planets, but their number is far greater, and their combined surface area likely dwarfs the Earth's. An asteroid survey will dramatically increase our understanding of the local resources available for the Human Exploration and Development of Space. During the mission composition, shape, gravity, and orbit parameters could be returned to Earth for perhaps several thousand asteroids. A survey of this area will rival the great explorations that encircled this globe, opened up the New World, and laid the groundwork for the progress and challenges of the last centuries. The ANTS architecture for a main belt survey consists of a swarm of as many as a thousand or more highly specialized pico-spacecraft that form teams to survey as many as one hundred asteroids a month. Multi-level autonomy is critical for ANTS and the objective of the proposed study is to work through the implications and constraints this entails. ANTS couples biologically inspired autonomic control for basic functions to higher level artificial intelligence that together enable individual spacecraft to operate as specialized, cooperative, social agents. This revolutionary approach postulates highly advanced, but familiar, components integrated and operated in a way that uniquely transcends any evolutionary extrapolation of existing trends and enables thousand-spacecraft missions.

Clark, P. E.; Rilee, M. L.; Curtis, S.; Truszkowski, W.

2002-05-01

193

Appeared in Ant Algorithms Proceedings of ANTS 2002, Third International Workshop on Ant Algorithms, Brussels, Belgium, September 12--14, 2002, SpringerVerlag, Lecture Notes in  

E-print Network

Appeared in Ant Algorithms ­ Proceedings of ANTS 2002, Third International Workshop on Ant. 2463, 2002 Toward the formal foundation of Ant Programming Mauro Birattari, Gianni Di Caro, and Marco,gdicaro,mdorigog@ulb.ac.be Abstract This paper develops the formal framework of ant programming with the goal of gaining a deeper

Ducatelle, Frederick

194

Mimetic host shifts in an endangered social parasite of ants.  

PubMed

An emerging problem in conservation is whether listed morpho-species with broad distributions, yet specialized lifestyles, consist of more than one cryptic species or functionally distinct forms that have different ecological requirements. We describe extreme regional divergence within an iconic endangered butterfly, whose socially parasitic young stages use non-visual, non-tactile cues to infiltrate and supplant the brood in ant societies. Although indistinguishable morphologically or when using current mitochondrial and nuclear sequence-, or microsatellite data, Maculinea rebeli from Spain and southeast Poland exploit different Myrmica ant species and experience 100 per cent mortality with each other's hosts. This reflects major differences in the hydrocarbons synthesized from each region by the larvae, which so closely mimic the recognition profiles of their respective hosts that nurse ants afford each parasite a social status above that of their own kin larvae. The two host ants occupy separate niches within grassland; thus, conservation management must differ in each region. Similar cryptic differentiation may be common, yet equally hard to detect, among the approximately 10 000 unstudied morpho-species of social parasite that are estimated to exist, many of which are Red Data Book listed. PMID:23193127

Thomas, Jeremy A; Elmes, Graham W; Sielezniew, Marcin; Stankiewicz-Fiedurek, Anna; Simcox, David J; Settele, Josef; Schönrogge, Karsten

2013-01-22

195

Blind and myopic ants in heterogeneous networks.  

PubMed

The diffusion processes on complex networks may be described by different Laplacian matrices due to heterogeneous connectivity. Here we investigate the random walks of blind ants and myopic ants on heterogeneous networks: While a myopic ant hops to a neighbor node every step, a blind ant may stay or hop with probabilities that depend on node connectivity. By analyzing the trajectories of blind ants, we show that the asymptotic behaviors of both random walks are related by rescaling time and probability with node connectivity. Using this result, we show how the small eigenvalues of the Laplacian matrices generating the two random walks are related. As an application, we show how the return-to-origin probability of a myopic ant can be used to compute the scaling behaviors of the Edwards-Wilkinson model, a representative model of load balancing on networks. PMID:25493841

Hwang, S; Lee, D-S; Kahng, B

2014-11-01

196

Blind and myopic ants in heterogeneous networks  

NASA Astrophysics Data System (ADS)

The diffusion processes on complex networks may be described by different Laplacian matrices due to heterogeneous connectivity. Here we investigate the random walks of blind ants and myopic ants on heterogeneous networks: While a myopic ant hops to a neighbor node every step, a blind ant may stay or hop with probabilities that depend on node connectivity. By analyzing the trajectories of blind ants, we show that the asymptotic behaviors of both random walks are related by rescaling time and probability with node connectivity. Using this result, we show how the small eigenvalues of the Laplacian matrices generating the two random walks are related. As an application, we show how the return-to-origin probability of a myopic ant can be used to compute the scaling behaviors of the Edwards-Wilkinson model, a representative model of load balancing on networks.

Hwang, S.; Lee, D.-S.; Kahng, B.

2014-11-01

197

Computer Science Department June 1990 GENETIC PROGRAMMING: A PARADIGM FOR GENETICALLY  

E-print Network

MUIR TRAIL 33 4.3. ........SYMBOLIC FUNCTION IDENTIFICATION 35 4.3.1.......SEQUENCE INDUCTION 35 4 POPULATIONS OF COMPUTER PROGRAMS TO SOLVE PROBLEMS John R. Koza (Koza@Sunburn.Stanford.Edu) Computer Science.2.4. .....A PARSIMONIOUS EXPRESSION FOR STACKING BLOCKS 32 4.2.5. .....ARTIFICIAL ANT - TRAVERSING THE JOHN

Fernandez, Thomas

198

8.EE Ants versus humans  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: The average mass of an adult human is about 65 kilograms while the average mass of an ant is approximately $4 \\times 10^{-3}$ grams. The total human po...

2012-08-21

199

Ant cuticular response to phthalate pollution.  

PubMed

Phthalates are common atmospheric contaminants used in the plastic industry. Ants have been shown to constitute good bioindicators of phthalate pollution. Hence, phthalates remain trapped on ant cuticles which are mostly coated with long-chain hydrocarbons. In this study, we artificially contaminated Lasius niger ants with four phthalates: dibutyl phthalate (DBP), diisobutyl phthalate (DiBP), di(2-ethylhexyl) phthalate (DEHP), and benzyl butyl phthalate (BBP). The first three have previously been found on ants in nature in Touraine (France), while the fourth has not. The four phthalates disappeared rapidly (less than 5 days) from the cuticles of live ants. In contrast, on the cuticles of dead ants, DEHP quantities remained unchanged over time. These results indicate that phthalates are actively absorbed by the cuticles of live ants. Cuticular absorption of phthalates is nonspecific because eicosane, a nonnatural hydrocarbon on L. niger cuticle, was similarly absorbed. Ants are important ecological engineers and may serve as bioindicators of ecosystem health. We also suggest that ants and more generally terrestrial arthropods may contribute to the removal of phthalates from the local environment. PMID:25012205

Lenoir, Alain; Touchard, Axel; Devers, Séverine; Christidès, Jean-Philippe; Boulay, Raphaël; Cuvillier-Hot, Virginie

2014-12-01

200

An adaptive multiagent routing algorithm inspired by ants behavior  

E-print Network

An adaptive multi­agent routing algorithm inspired by ants behavior Gianni Di Caro and Marco Dorigo introduces AntNet, a novel adaptive approach to routing tables learning in connectionless communications networks. AntNet is inspired by the stigmergy communication model observed in ant colonies. We compare Ant

Ducatelle, Frederick

201

Imported Fire Ants: An Agricultural Pest and a  

E-print Network

Imported Fire Ants: An Agricultural Pest and a Human Health Hazard Imported fire ants (Solenopsis. The black imported fire ant was brought to Mobile, AL, in 1918. The red imported fire ant arrived) Animal and Plant Health Inspection Service (APHIS) for advice about how to manage imported fire ants

Balasundaram, Balabhaskar "Baski"

202

Competitive Mechanisms Underlying the Displacement of Native Ants by the Invasive Argentine Ant  

Microsoft Academic Search

The Argentine ant (Linepithema humile) is a widespread invasive species that competitively displaces native ants throughout its introduced range. Although this pattern of displacement is well known, its underlying mechanisms remain little studied. To gain a more detailed understanding of this widespread competitive displacement, I compared the exploitative and interference abilities of the Argentine ant with those of seven species

David A. Holway

1999-01-01

203

Ants and extrafloral nectaries: no evidence for plant protection in Helichrysum spp. — ant interactions  

Microsoft Academic Search

Characterstics of Australian endemic Helichrysum bracteratum and H. viscosum suggest that foraging ants act as “guards” of developing flowerheads, protecting capitula from seed predators: (1) extrafloral nectar is secreted from leaves subtending the capitula and from bracts encircling the floral disc during pre- to post-flowering periods; (2) capitula are attended by ants; and, (3) encounters between ants and other capitula

Dennis J. O'Dowd; E. A. Catchpole

1983-01-01

204

Ant system: optimization by a colony of cooperating agents.  

PubMed

An analogy with the way ant colonies function has suggested the definition of a new computational paradigm, which we call ant system (AS). We propose it as a viable new approach to stochastic combinatorial optimization. The main characteristics of this model are positive feedback, distributed computation, and the use of a constructive greedy heuristic. Positive feedback accounts for rapid discovery of good solutions, distributed computation avoids premature convergence, and the greedy heuristic helps find acceptable solutions in the early stages of the search process. We apply the proposed methodology to the classical traveling salesman problem (TSP), and report simulation results. We also discuss parameter selection and the early setups of the model, and compare it with tabu search and simulated annealing using TSP. To demonstrate the robustness of the approach, we show how the ant system (AS) can be applied to other optimization problems like the asymmetric traveling salesman, the quadratic assignment and the job-shop scheduling. Finally we discuss the salient characteristics-global data structure revision, distributed communication and probabilistic transitions of the AS. PMID:18263004

Dorigo, M; Maniezzo, V; Colorni, A

1996-01-01

205

The beauty of ant antics DeborahM.Gordon enjoys a photographic paean to individual ants and their rarely glimpsed  

E-print Network

The beauty of ant antics DeborahM.Gordon enjoys a photographic paean to individual ants and their rarely glimpsed exploits on behalf of the collective. Ant expert and photographer Mark Moffett likes to explore. In Adventures Among Ants, he describes his tropical encounters with his favourite kind of ant

Gordon, Deborah

206

A Hybrid Ant Colony Algorithm for Loading Pattern Optimization  

NASA Astrophysics Data System (ADS)

Electricité de France (EDF) operates 58 nuclear power plant (NPP), of the Pressurized Water Reactor (PWR) type. The loading pattern (LP) optimization of these NPP is currently done by EDF expert engineers. Within this framework, EDF R&D has developed automatic optimization tools that assist the experts. The latter can resort, for instance, to a loading pattern optimization software based on ant colony algorithm. This paper presents an analysis of the search space of a few realistic loading pattern optimization problems. This analysis leads us to introduce a hybrid algorithm based on ant colony and a local search method. We then show that this new algorithm is able to generate loading patterns of good quality.

Hoareau, F.

2014-06-01

207

Key to Identifying Common Household Ants  

NSDL National Science Digital Library

A short lucid key to 8 common household ant species with control strategies. The information presented is accurate and the key easy to use; ancillary pages are also useful. The key may present difficulties if other ant species are encountered or in other parts of the U.S.

0002-11-30

208

Community ecology Ants defend aphids against  

E-print Network

Community ecology Ants defend aphids against lethal disease Charlotte Nielsen1,, Anurag A. Agrawal1 colonies and some species also protect their mutualist partners. In mutualisms with aphids, ants typically feed on honeydew produced by aphids and, in turn guard and shelter aphid colonies from insect natural

Agrawal, Anurag

209

The Use of Ants in Field Work.  

ERIC Educational Resources Information Center

Provided is a brief description of the biology and taxonomy of British ants. Suggested are a range of exercises which could be used for class or project work in secondary biology classes. Illustrates many ecological, behavioral and physiological points regarding the species of ants found in Great Britain. (Author/CW)

Skinner, Gary J.

1988-01-01

210

Operant conditioning in the ant Myrmica sabuleti  

Microsoft Academic Search

Operant conditioning could be obtained in the ant Myrmica sabuleti by presenting to the workers, during a six-day period, an apparatus containing either sugared water or meat as a reward. The conditioning obtained using sugared water as a reward was short lasting. A reconditioning was more persistent and lasted four hours. The ants’ response was very precise, since they exhibited

M. C. Cammaerts

2004-01-01

211

Extrafloral nectar fuels ant life in deserts.  

PubMed

Interactions mediated by extrafloral nectary (EFN)-bearing plants that reward ants with a sweet liquid secretion are well documented in temperate and tropical habitats. However, their distribution and abundance in deserts are poorly known. In this study, we test the predictions that biotic interactions between EFN plants and ants are abundant and common also in arid communities and that EFNs are only functional when new vegetative and reproductive structures are developing. In a seasonal desert of northwestern Argentina, we surveyed the richness and phenology of EFN plants and their associated ants and examined the patterns in ant-plant interaction networks. We found that 25 ant species and 11 EFN-bearing plant species were linked together through 96 pairs of associations. Plants bearing EFNs were abundant, representing ca. 19 % of the species encountered in transects and 24 % of the plant cover. Most ant species sampled (ca. 77 %) fed on EF nectar. Interactions showed a marked seasonal pattern: EFN secretion was directly related to plant phenology and correlated with the time of highest ant ground activity. Our results reveal that EFN-mediated interactions are ecologically relevant components of deserts, and that EFN-bearing plants are crucial for the survival of desert ant communities. PMID:25381258

Aranda-Rickert, Adriana; Diez, Patricia; Marazzi, Brigitte

2014-01-01

212

Butterfly larvae fool ants into mothering them  

NSDL National Science Digital Library

Danish researchers have found that in some areas in their country, beautiful blue Alcon butterflies fool ants into raising the butterfly larvae instead of their own, a report explains. The reason? The butterflies have developed an outer coating that mimics that of the ants.

American Association for the Advancement of Science (AAAS;)

2008-01-03

213

Particle Swarm and Ant Colony Approaches in Multiobjective Optimization  

NASA Astrophysics Data System (ADS)

The social behavior of groups of birds, ants, insects and fish has been used to develop evolutionary algorithms known as swarm intelligence techniques for solving optimization problems. This work presents the development of strategies for the application of two of the popular swarm intelligence techniques, namely the particle swarm and ant colony methods, for the solution of multiobjective optimization problems. In a multiobjective optimization problem, the objectives exhibit a conflicting nature and hence no design vector can minimize all the objectives simultaneously. The concept of Pareto-optimal solution is used in finding a compromise solution. A modified cooperative game theory approach, in which each objective is associated with a different player, is used in this work. The applicability and computational efficiencies of the proposed techniques are demonstrated through several illustrative examples involving unconstrained and constrained problems with single and multiple objectives and continuous and mixed design variables. The present methodologies are expected to be useful for the solution of a variety of practical continuous and mixed optimization problems involving single or multiple objectives with or without constraints.

Rao, S. S.

2010-10-01

214

Spatiotemporal chemotactic model for ant foraging  

NASA Astrophysics Data System (ADS)

In this paper, we present a generic theoretical chemotactic model that accounts for certain emergent behaviors observed in ant foraging. The model does not have many of the constraints and limitations of existing models for ants colony dynamics and takes into account the distinctly different behaviors exhibited in nature by ant foragers in search of food and food ferrying ants. Numerical simulations based on the model show trail formation in foraging ant colonies to be an emergent phenomenon and, in particular, replicate behavior observed in experiments involving the species P. megacephala. The results have broader implications for the study of randomness in chemotactic models. Potential applications include the developments of novel algorithms for stochastic search in engineered complex systems such as robotic swarms.

Ramakrishnan, Subramanian; Laurent, Thomas; Kumar, Manish; Bertozzi, Andrea L.

2014-12-01

215

Ants defend aphids against lethal disease.  

PubMed

Social insects defend their own colonies and some species also protect their mutualist partners. In mutualisms with aphids, ants typically feed on honeydew produced by aphids and, in turn guard and shelter aphid colonies from insect natural enemies. Here we report that Formica podzolica ants tending milkweed aphids, Aphis asclepiadis, protect aphid colonies from lethal fungal infections caused by an obligate aphid pathogen, Pandora neoaphidis. In field experiments, bodies of fungal-killed aphids were quickly removed from ant-tended aphid colonies. Ant workers were also able to detect infective conidia on the cuticle of living aphids and responded by either removing or grooming these aphids. Our results extend the long-standing view of ants as mutualists and protectors of aphids by demonstrating focused sanitizing and quarantining behaviour that may lead to reduced disease transmission in aphid colonies. PMID:19923138

Nielsen, Charlotte; Agrawal, Anurag A; Hajek, Ann E

2010-04-23

216

How to be an ant on figs  

NASA Astrophysics Data System (ADS)

Mutualistic interactions are open to exploitation by one or other of the partners and a diversity of other organisms, and hence are best understood as being embedded in a complex network of biotic interactions. Figs participate in an obligate mutualism in that figs are dependent on agaonid fig wasps for pollination and the wasps are dependent on fig ovules for brood sites. Ants are common insect predators and abundant in tropical forests. Ants have been recorded on approximately 11% of fig species, including all six subgenera, and often affect the fig-fig pollinator interaction through their predation of either pollinating and parasitic wasps. On monoecious figs, ants are often associated with hemipterans, whereas in dioecious figs ants predominantly prey on fig wasps. A few fig species are true myrmecophytes, with domatia or food rewards for ants, and in at least one species this is linked to predation of parasitic fig wasps. Ants also play a role in dispersal of fig seeds and may be particularly important for hemi-epiphytic species, which require high quality establishment microsites in the canopy. The intersection between the fig-fig pollinator and ant-plant systems promises to provide fertile ground for understanding mutualistic interactions within the context of complex interaction networks.

Bain, Anthony; Harrison, Rhett D.; Schatz, Bertrand

2014-05-01

217

Regulation of ants' foraging to resource productivity.  

PubMed Central

We investigate the behavioural rule used by ant societies to adjust their foraging response to the honeydew productivity of aphids. When a scout finds a single food source, the decision to lay a recruitment trail is an all-or-none response based on the opportunity for this scout to ingest a desired volume acting as a threshold. Here, we demonstrate, through experimental and theoretical approaches, the generic value of this recruitment rule that remains valid when ants have to forage on multiple small sugar feeders to reach their desired volume. Moreover, our experiments show that when ants decide to recruit nest-mates they lay trail marks of equal intensity, whatever the number of food sources visited. A model based on the 'desired volume' rule of recruitment as well as on experimentally validated parameter values was built to investigate how ant societies adjust their foraging response to the honeydew productivity profile of aphids. Simulations predict that, with such recruiting rules, the percentage of recruiting ants is directly related to the total production of honeydew. Moreover, an optimal number of foragers exists that maximizes the strength of recruitment, this number being linearly related to the total production of honeydew by the aphid colony. The 'desired volume' recruitment rule that should be generic for all ant species is enough to explain how ants optimize trail recruitment and select aphid colonies or other liquid food resources according to their productivity profile. PMID:12908982

Mailleux, Anne-Catherine; Deneubourg, Jean-Louis; Detrain, Claire

2003-01-01

218

Pheromone disruption of Argentine ant trail integrity  

USGS Publications Warehouse

Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

2008-01-01

219

Ant Colonies Shed Light on Metabolism  

NSDL National Science Digital Library

Press Release. Ants are usually regarded as the unwanted guests at a picnic. But a recent study of California seed harvester ants (Pogonomyrmex californicus) examining their metabolic rate in relation to colony size may lead to a better appreciation for the social, six-legged insects, whose colonies researchers say provide a theoretical framework for understanding cellular networks. Mr. Waters presented his paper, Scaling of Metabolism, Growth and Network Organization in Colonies of the Seed Harvester Ant, Pogonomyrmex californicus, at the American Physiological SocietyÂ?s Intersociety Meeting Global Science: Comparative Physiology in a Changing World. The program is located at http://the-aps.org/meetings/aps/comparative/preprogram.htm.

APS Communications Office (American Physiological Society Communications Office)

2010-08-26

220

A Stochastic Inversion Method for Potential Field Data: Ant Colony Optimization  

NASA Astrophysics Data System (ADS)

Simulating natural ants' foraging behavior, the ant colony optimization (ACO) algorithm performs excellently in combinational optimization problems, for example the traveling salesman problem and the quadratic assignment problem. However, the ACO is seldom used to inverted for gravitational and magnetic data. On the basis of the continuous and multi-dimensional objective function for potential field data optimization inversion, we present the node partition strategy ACO (NP-ACO) algorithm for inversion of model variables of fixed shape and recovery of physical property distributions of complicated shape models. We divide the continuous variables into discrete nodes and ants directionally tour the nodes by use of transition probabilities. We update the pheromone trails by use of Gaussian mapping between the objective function value and the quantity of pheromone. It can analyze the search results in real time and promote the rate of convergence and precision of inversion. Traditional mapping, including the ant-cycle system, weaken the differences between ant individuals and lead to premature convergence. We tested our method by use of synthetic data and real data from scenarios involving gravity and magnetic anomalies. The inverted model variables and recovered physical property distributions were in good agreement with the true values. The ACO algorithm for binary representation imaging and full imaging can recover sharper physical property distributions than traditional linear inversion methods. The ACO has good optimization capability and some excellent characteristics, for example robustness, parallel implementation, and portability, compared with other stochastic metaheuristics.

Liu, Shuang; Hu, Xiangyun; Liu, Tianyou

2014-07-01

221

Reactions by army ant workers to nestmates having had contact with sympatric ant species.  

PubMed

It was recently shown that Pheidole megacephala colonies (an invasive species originating from Africa) counterattack when raided by the army ant, Eciton burchellii. The subsequent contact permits Pheidole cuticular compounds (that constitute the "colony odour") to be transferred onto the raiding Eciton, which are then not recognised by their colony-mates and killed. Using a simple method for transferring cuticular compounds, we tested if this phenomenon occurs for Neotropical ants. Eciton workers rubbed with ants from four sympatric species were released among their colony-mates. Individuals rubbed with Solenopsis saevissima or Camponotus blandus workers were attacked, but not those rubbed with Atta sexdens, Pheidole fallax or with colony-mates (control lot). So, the chemicals of certain sympatric ant species, but not others, trigger intra-colonial aggressiveness in Eciton. We conclude that prey-ant chemicals might have played a role in the evolution of army ant predatory behaviour, likely influencing prey specialization in certain cases. PMID:25444708

Dejean, Alain; Corbara, Bruno

2014-11-01

222

Plants in Your Ants: Using Ant Mounds to Test Basic Ecological Principles  

NSDL National Science Digital Library

[PDF] Article from The American Biology Teacher, Vol. 72, No. 3, pages 173?176. ISSN 0002-7685, electronic ISSN 1938?4211. ©2010 by National Association of Biology Teachers. This is an article about providing urban students with a field site for ecological studies, using ants and their mounds. The authors describe how soil collected from ant mounds can be used to investigate how biotic factors (ants) can affect abiotic factors in the soil that can, in turn, influence plant growth.

Zettler, Jennifer A.

223

Ant assemblages in the taiga biome: testing the role of territorial wood ants  

Microsoft Academic Search

Ants were collected with sets of pitfall traps in four coniferous-forest habitats in southern Finland. A three-level competition hierarchy concept was used to generate predictions on ant community structure. The levels of the hierarchy, and the respective predictions, from top to bottom were: (1) The dominant territorial wood ants (Formica rufa-group species), expected to exclude each other. (2) The other

R. Savolainen; K. Vepsäläinen; H. Wuorenrinne

1989-01-01

224

Ant eating behavior of mountain gorillas  

Microsoft Academic Search

Eleven cases of feeding on driver ants (Dorylus sp.) by mountain gorillas (Gorilla gorilla beringei) are described. Ant eating provides the gorillas with more animal protein and other nutrients per unit feeding time than\\u000a do other forms of insectivory that contribute to their diet, but it is so rare that it is unlikely to be of real nutritional\\u000a significance. Gorillas

David P. Watts

1989-01-01

225

Ant functional responses along environmental gradients.  

PubMed

Understanding species distributions and diversity gradients is a central challenge in ecology and requires prior knowledge of the functional traits mediating species' survival under particular environmental conditions. While the functional ecology of plants has been reasonably well explored, much less is known about that of animals. Ants are among the most diverse, abundant and ecologically significant organisms on earth, and they perform a great variety of ecological functions. In this study, we analyse how the functional species traits present in ant communities vary along broad gradients in climate, productivity and vegetation type in the south-western Mediterranean. To this end, we compiled one of the largest animal databases to date: it contains information on 211 local ant communities (including eight climate variables, productivity, and vegetation type) and 124 ant species, for which 10 functional traits are described. We used traits that characterize different dimensions of the ant functional niche with respect to morphology, life history and behaviour at both individual and colony level. We calculated two complementary functional trait community indices ('trait average' and 'trait dissimilarity') for each trait, and we analysed how they varied along the three different gradients using generalized least squares models that accounted for spatial autocorrelation. Our results show that productivity, vegetation type and, to a lesser extent, each climate variable per se might play an important role in shaping the occurrence of functional species traits in ant communities. Among the climate variables, temperature and precipitation seasonality had a much higher influence on functional responses than their mean values, whose effects were almost lacking. Our results suggest that strong relationships might exist between the abiotic environment and the distribution of functional traits among south-western Mediterranean ant communities. This finding indicates that functional traits may modulate the responses of ant species to the environment. Since these traits act as the link between species distributions and the environment, they could potentially be used to predict community changes under future global change scenarios. PMID:24720700

Arnan, Xavier; Cerdá, Xim; Retana, Javier

2014-04-11

226

Science Nation: Leaf-cutter Ants  

NSDL National Science Digital Library

In established colonies, millions of leaf-cutter ants cut and carry sections of leaves larger than their own bodies as part of a well choreographed, highly functioning society. With support from the National Science Foundation (NSF),bacteriologist Cameron Currie and his team study ants and their complex, productive societies to help address some of human society's most pressing challenges, such as better drugs and cleaner energy.

227

ORIGINAL ARTICLE Collective decisions in ants when foraging  

E-print Network

ORIGINAL ARTICLE Collective decisions in ants when foraging under crowded conditions Audrey-recruiting ant Lasius niger. In our experiment, ants had to go from their nest to a food source by crossing underlying the choice of route in ants. A mathematical model was developed to evaluate the impor- tance

Nicolis, Stamatios C.

228

Ant Foraging Revisited Liviu A. Panait and Sean Luke  

E-print Network

Ant Foraging Revisited Liviu A. Panait and Sean Luke George Mason University, Fairfax, VA 22030 lpanait@cs.gmu.edu, sean@cs.gmu.edu Abstract Most previous artificial ant foraging algorithms have to date the artificial ants with the knowledge of the nest direction. In contrast, the work presented solves ant foraging

Turk, Greg

229

Ant-Inspired Navigation In Unknown Environments Stergios I. Roumeliotis  

E-print Network

Ant-Inspired Navigation In Unknown Environments Stergios I. Roumeliotis Computer Science Dpt-0781 maja@robotics.usc.edu In contrast to mostother ant species, desert ants (Cataglyphis fortis) do not use) information. Indeed desert ants and honeybees use such information in addition to path integration. On a fa

Roumeliotis, Stergios I.

230

When Fire Ants Move In, Others Leave Elizabeth Pennisi  

E-print Network

ECOLOGY: When Fire Ants Move In, Others Leave Elizabeth Pennisi For Amy Arnett, getting a Ph, collecting ants at 33 sites along the way. They had set out to look at how the food resources for ant lions, insects that prey on ants, changed from north to south along the East Coast. But in the process

Gotelli, Nicholas J.

231

A Deterministic Metaheuristic Approach Using "Logistic Ants" for Combinatorial Optimization  

E-print Network

A Deterministic Metaheuristic Approach Using "Logistic Ants" for Combinatorial Optimization-l`es-Nancy, France rodolphe.charrier@loria.fr Abstract. Ant algorithms are usually derived from a stochastic mod of "logistic ants" which uses chaotic maps to govern the behavior of the artificial ants. We illustrate

Paris-Sud XI, Université de

232

Chemically armed mercenary ants protect fungus-farming societies  

E-print Network

Chemically armed mercenary ants protect fungus-farming societies Rachelle M. M. Adamsa,b,1 June 20, 2013) The ants are extraordinary in having evolved many lineages that exploit closely related ant societies as social parasites, but social parasitism by distantly related ants is rare. Here we

Schultz, Ted

233

Ant Colony Optimisation1 12.1 Introduction  

E-print Network

Chapter 12 Ant Colony Optimisation1 12.1 Introduction Real ants can find a shortest path from the old one is no longer feasible due to a new obstacle. In Figure (12.1 A) ants are moving on a straight line that connects a food source to their nest. An ant: · deposits pheromone while walking

Grant, P. W.

234

Ant Foraging Revisited Liviu A. Panait and Sean Luke  

E-print Network

Ant Foraging Revisited Liviu A. Panait and Sean Luke George Mason University, Fairfax, VA 22030 lpanait@cs.gmu.edu, sean@cs.gmu.edu Abstract Most previous artificial ant foraging models have to date re the artificial ants with the knowledge of the nest direction. In contrast, the work presented solves ant foraging

George Mason University

235

SCHOOLS INTEGRATED PEST MANAGEMENT (IPM) FOR ANTS *Important Note*  

E-print Network

and help control other pests, including fly larvae, crickets, and termites. Some species of ants colonies. Males die soon after mating. Winged ants are often confused with termites (see Figure 2). However, ants are distinguished from termites by three distinct features. First, ants have elbowed antennae

Liskiewicz, Maciej

236

Symbiont choice in a fungus-growing ant (Attini, Formicidae)  

Microsoft Academic Search

Cultivars of fungus-growing (attine) ants are vertically transmitted through inheritance from parent to offspring nest, but horizontal cultivar transfer between ant nests occurs occasionally, resulting in cultivar replacement within ant lineages. Two mechanisms could theoretically prevent the invasion of suboptimal cultivar strains and thus stabilize ant--cultivar coevolution: first, partner feedback inherent in vertical cultivar transmission and second, partner (symbiont) choice

Ulrich G. Mueller; Jessica Poulin; Rachelle M. M. Adamsa

2004-01-01

237

Leaf litter ant diversity in Guyana JOHN S. LAPOLLA1,  

E-print Network

-1 Leaf litter ant diversity in Guyana JOHN S. LAPOLLA1, *, TED SUMAN1 , JEFFREY SOSA-CALVO1 Shield, Leaf litter ants Abstract. Leaf litter ants are an important group of organisms for informing conservation plan- ning. This study presents the beginning of a leaf litter ant dataset for Guyana. Following

Schultz, Ted

238

Of ants and urns: estimation of the parameters of a reinforced random walk and application to ants  

E-print Network

Of ants and urns: estimation of the parameters of a reinforced random walk and application to ants of a path by laboratory ants. We study our estimators in a general framework and then restrict to a particular model in order to do a simulation study and an application to a an experiment with ants. Our

Paris-Sud XI, Université de

239

Summary. The Argentine ant, Linepithema humile, has invaded many areas of the world, displacing native ants. Its  

E-print Network

Summary. The Argentine ant, Linepithema humile, has invaded many areas of the world, displacing native ants. Its behavior may contribute to its competitive success. Staged and natural encounters were observed at food resources in the field, between Argentine ants and eight ant species native to northern

Gordon, Deborah

240

Texas Imported Fire Ant Research and Management Plan  

NSDL National Science Digital Library

The Department of Entomology at Texas A&M University provides this informative Web site focused on the invasive imported fire ant. Visitors will find all the latest in fire ant research and management, as well as an introduction to fire ant natural history and environmental impact. Materials include multimedia presentations, downloadable publications and factsheets, and lots of related links. Visitors can also check out an audio clip of fire ant stridulations -- a weird little sound the ants make rubbing thorax against abdomen.

241

Data mining with an ant colony optimization algorithm  

Microsoft Academic Search

This work proposes an algorithm for data mining called Ant-Miner (Ant Colony-based Data Miner). The goal of Ant-Miner is to extract classification rules from data. The algorithm is inspired by both research on the behavior of real ant colonies and some data mining concepts and principles. We compare the performance of Ant-Miner with CN2, a well-known data mining algorithm for

Rafael S. Parpinelli; Heitor S. Lopes; Alex Alves Freitas

2002-01-01

242

Mining Spatial Trends by a Colony of Cooperative Ant Agents Ashkan Zarnani  

E-print Network

Mining Spatial Trends by a Colony of Cooperative Ant Agents Ashkan Zarnani Masoud Rahgozar Abstract the highly demanding field of spatial data mining. So far many optimization problems have been better solved and retailing. These are valuable mines of knowledge vital for strategic decision making and motivate the highly

Bailey-Kellogg, Chris

243

Scheduling continuous casting of aluminum using a multiple objective ant colony optimization metaheuristic  

Microsoft Academic Search

This paper presents an ant colony optimization metaheuristic for the solution of an industrial scheduling problem in an aluminum casting center. We present an efficient representation of a continuous horizontal casting process which takes account of a number of objectives that are important to the scheduler. We have incorporated the methods proposed in software that has been implemented in the

Marc Gravel; Wilson L. Price; Caroline Gagné

2002-01-01

244

On some applications of ant colony optimization metaheuristic to plane truss optimization  

Microsoft Academic Search

Ant colony optimization metaheuristic (ACO) represents a new class of algorithms particularly suited to solve real-world combinatorial optimization problems. ACO algorithms, published for the first time in 1991 by M. Dorigo [Optimization, learning and natural algorithms (in Italian). Ph.D. Thesis, Dipartimento di Elettronica, Politecnico di Milano, Milan, 1992] and his coworkers, have been applied, particularly starting from 1999 (Bonabeau et

M. Serra; P. Venini

2006-01-01

245

Ant Colony Optimization Algorithm for Continuous Domains Based on Position Distribution Model of Ant Colony Foraging  

PubMed Central

Ant colony optimization algorithm for continuous domains is a major research direction for ant colony optimization algorithm. In this paper, we propose a distribution model of ant colony foraging, through analysis of the relationship between the position distribution and food source in the process of ant colony foraging. We design a continuous domain optimization algorithm based on the model and give the form of solution for the algorithm, the distribution model of pheromone, the update rules of ant colony position, and the processing method of constraint condition. Algorithm performance against a set of test trials was unconstrained optimization test functions and a set of optimization test functions, and test results of other algorithms are compared and analyzed to verify the correctness and effectiveness of the proposed algorithm. PMID:24955402

Liu, Liqiang; Dai, Yuntao

2014-01-01

246

Ant odometry in the third dimension.  

PubMed

Desert ants (Cataglyphis) are renowned for their ability to perform large-scale foraging excursions and then return to the nest by path integration. They do so by integrating courses steered and the distances travelled into a continually updated home vector. Whereas the angular orientation is based on skylight cues, how the ants gauge the distances travelled has remained largely unclear. Furthermore, almost all studies on path integration in Cataglyphis, as well as in spiders, rodents, and humans, have aimed at understanding how the animals compute homebound courses in the horizontal plane. Here, we investigate for the first time how an animal's odometer operates when a path integration task has to be accomplished that includes a vertical component. We trained Cataglyphis ants within arrays of uphill and downhill channels, and later tested them on flat terrain, or vice versa. In all these cases, the ants indicated homing distances that corresponded not to the distances actually travelled but to the ground distances; that is, to the sum of the horizontal projections of the uphill and downhill segments of the ants' paths. PMID:11459057

Wohlgemuth, S; Ronacher, B; Wehner, R

2001-06-14

247

Impacts of residual insecticide barriers on perimeter-invading ants, with particular reference to the odorous house ant, Tapinoma sessile.  

PubMed

Three liquid insecticide formulations were evaluated as barrier treatments against perimeter-invading ants at a multifamily housing complex in West Lafayette, IN. Several ant species were present at the study site, including (in order of abundance) pavement ant, Tetramorium caespitum (L.); honey ant, Prenolepis imparis (Say); odorous house ant, Tapinoma sessile (Say); thief ant, Solenopsis molesta (Say); acrobat ant, Crematogaster ashmeadi (Mayr); crazy ant, Paratrechina longicornis (Latrielle), field ants, Formica spp.; and carpenter ant Camponotus pennsylvanicus (DeGeer). Studies began in May 2001 and concluded 8 wk later in July. Individual replicate treatments were placed 0.61 in (2 feet) up and 0.92 m (3 feet) out from the ends of 46.1 by 10.1-m (151 by 33-foot) apartment buildings. Ant sampling was performed with 10 placements of moist cat food for 1 h within treatment zones, followed by capture and removal of recruited ants for later counting. All treatments led to substantial reductions in ant numbers relative to untreated controls. The most effective treatment was fipronil, where 2% of before-treatment ant numbers were present at 8 wk after treatment. Both imidacloprid and cyfluthrin barrier treatments had efficacy comparative with fipronil, but to 4 and 2 wk, respectively. Odorous house ants were not sampled before treatment. Comparisons of ant species composition between treatments and controls revealed an increase in odorous house ant frequencies at 1-8 wk after treatment in treated locations only. These results demonstrate efficacy for both nonrepellent and repellent liquid insecticides as perimeter treatments for pest ants. In addition, our findings with odorous house ant highlight an apparent invasive-like characteristic of this species that may contribute to its dramatic increase in structural infestation rates in many areas of the United States. PMID:15154488

Scharf, Michael E; Ratliff, Catina R; Bennett, Gary W

2004-04-01

248

Haemolytic uremic syndrome following fire ant bites  

PubMed Central

Background Haemolytic-uremic syndrome (HUS) is a severe, life-threatening disease with symptoms such as haemolytic anaemia, renal failure, and a low platelet count. Possible aetiology includes bacterial infections, medication, post-hematopoietic cell transplantation, pregnancy, autoimmune disease, and acquired immunodeficiency syndrome. Case presentation We report the case of a 21-year-old healthy man who developed acute renal failure caused by HUS. Typical symptoms of HUS combined with severe uraemia developed following a large local reaction after suspected Solenopsis invicta (fire ant) bites. He was successfully treated with plasma exchange and achieved complete recovery of renal function. Conclusion This is the first case illustrating a serious systemic reaction of HUS to fire ant bites, and highlights this severe complication in patients who sustain fire ant bites. PMID:24400942

2014-01-01

249

Ant-gardens of tropical Asian rainforests  

NASA Astrophysics Data System (ADS)

Ant-garden (AG) associations are systems of epiphytic plants and arboricolous (i.e., tree-living) ants, in which the ants build fragile carton nests containing organic material. They collect and incorporate seeds or fruits of epiphytes that then germinate and grow on the nest [sensu Corbara et al. (1999) 38:73-89]. The plant roots stabilize the nest carton. AGs have been well-known in the neotropics for more than 100 years. In contrast, reports on similar associations in the paleotropics are scarce so far. After discovering a first common AG system on giant bamboo [Kaufmann et al. (2001) 48:125-133], we started a large-scale survey for AGs in Peninsular Malaysia, Borneo, Java, and southern Thailand. A great variety of AG systems (altogether including 18 ant species and 51 plant species) was discovered and is described in the present paper. The high number of species participating in AG associations was reflected by a great variability in the specific appearances of the nest gardens. Frequently, further groups of organisms (e.g., hemipteran trophobionts, fungi) were also involved. Preference patterns of particular ant and epiphyte species for each other and for particular phorophytes (carrier trees) were detected. We integrate domatia-producing, so-called ant-house epiphytes in our study and compare their phases of establishment, as well as other characteristics, to “classical” AGs, coming to the conclusion that they should be regarded only as a special type of AG epiphyte and not as a separate ecological category.

Kaufmann, Eva; Maschwitz, Ulrich

2006-05-01

250

A New Rank Based Version of the Ant System - A Computational Study  

Microsoft Academic Search

The ant system is a new meta-heuristic for hard combinatorial optimizationproblems. It is a population-based approach that uses exploitation of positivefeedback as well as greedy search. It was first proposed for tackling the wellknown Traveling Salesman Problem (TSP), but has been also successfully appliedto problems such as quadratic assignment, job-shop scheduling, vehiclerouting and graph colouring.In this paper we introduce a

Bernd Bullnheimer; Richard F. Hartl; Christine Strauß

1997-01-01

251

Application of Ant Colony Optimization Algorithm to Multi-Join Query Optimization  

Microsoft Academic Search

Multi-join query optimization (MJQO) is an important technique for designing and implementing database manage system. It is\\u000a a crucial factor that affects the capability of database. This paper proposes a new algorithm to solve the problem of MJQO\\u000a based on ant colony optimization (ACO). In this paper, details of the algorithm used to solve MJQO problem have been interpreted,\\u000a including

Nana Li; Yujuan Liu; Yongfeng Dong; Junhua Gu

2008-01-01

252

A Modified Discrete Binary Ant Colony Optimization and Its Application in Chemical Process Fault Diagnosis  

Microsoft Academic Search

Considering fault diagnosis is a small sample problem in real chemical process industry, Support Vector Machines (SVM) is\\u000a adopted as classifier to discriminate chemical process steady faults. To improve fault diagnosis performance, it is essential\\u000a to reduce the dimensionality of collected data. This paper presents a modified discrete binary ant colony optimization (MDBACO)\\u000a to optimize discrete combinational problems, and then

Ling Wang; Jinshou Yu

2006-01-01

253

Farmers, Warriors, Builders: The Hidden Life of Ants  

NSDL National Science Digital Library

The website of the Smithsonian National Museum of Natural History has a highly informative and just plain delightful interactive exhibit on ants. The exhibit explains how, much like humans, "ants achieve domination by being social creatures". Dividing the ants' lives into "food", "warriors", "shelter" and "communication", the exhibit offers an array of photos in its photo gallery to illustrate the variety of ant life and behavior on earth. Clicking on the thumbnails will enlarge the photos and reveal a brief description of the photo. More than half a dozen videos of ants taken throughout the world can be found under the "Ant Videos" link on the left side of the page. Visitors interested in learning more about myrmecology (ant science) would be remiss if they didn't visit the "Ant Web Links" section of the website, which can also be found on the left side of the page.

254

Fire Ants and the Decapitating Fly  

NSDL National Science Digital Library

Excellent summary of how the decapitating fly works as a biological control measure against fire ants. Unhurried pace with great supporting video. Good choice for introducing students to the idea of biological control. Video quality is extremely high and the depiction of the complete lifecycle of the fly is valuable.

0002-11-30

255

Wolbachia transmission dynamics in Formica wood ants  

Microsoft Academic Search

BACKGROUND: The role of Wolbachia endosymbionts in shaping the mitochondrial diversity of their arthropod host depends on the effects they have on host reproduction and on the mode of transmission of the bacteria. We have compared the sequence diversity of wsp (Wolbachia surface protein gene) and the host mtDNA in a group of Formica ant species that have diverged approximately

Lumi Viljakainen; Max Reuter; Pekka Pamilo

2008-01-01

256

URBAN PEST MANAGEMENT OF CARPENTER ANTS  

Microsoft Academic Search

In North America 20 species of Camponotus have been recorded as pest species causing either structural damage or occurring as nuisance species. Structurally damaging species are found in the subgenera: Camponotus. Tmaemyrmex, and Myrmothrix. Carpenter ants causing the most serious damage in eastern United States include C. pennsylvmicus, C. herculeanus, and C. noveboracenris while C. modoc and C. vicinus are

LAUREL D. HANSEN; ROGER D. AKRE

257

Ants recognize foes and not friends  

PubMed Central

Discriminating among individuals and rejecting non-group members is essential for the evolution and stability of animal societies. Ants are good models for studying recognition mechanisms, because they are typically very efficient in discriminating ‘friends’ (nest-mates) from ‘foes’ (non-nest-mates). Recognition in ants involves multicomponent cues encoded in cuticular hydrocarbon profiles. Here, we tested whether workers of the carpenter ant Camponotus herculeanus use the presence and/or absence of cuticular hydrocarbons to discriminate between nest-mates and non-nest-mates. We supplemented the cuticular profile with synthetic hydrocarbons mixed to liquid food and then assessed behavioural responses using two different bioassays. Our results show that (i) the presence, but not the absence, of an additional hydrocarbon elicited aggression and that (ii) among the three classes of hydrocarbons tested (unbranched, mono-methylated and dimethylated alkanes; for mono-methylated alkanes, we present a new synthetic pathway), only the dimethylated alkane was effective in eliciting aggression. Our results suggest that carpenter ants use a fundamentally different mechanism for nest-mate recognition than previously thought. They do not specifically recognize nest-mates, but rather recognize and reject non-nest-mates bearing odour cues that are novel to their own colony cuticular hydrocarbon profile. This begs for a reappraisal of the mechanisms underlying recognition systems in social insects. PMID:19364750

Guerrieri, Fernando J.; Nehring, Volker; Jørgensen, Charlotte G.; Nielsen, John; Galizia, C. Giovanni; d'Ettorre, Patrizia

2009-01-01

258

Water surface locomotion in tropical canopy ants.  

PubMed

Upon falling onto the water surface, most terrestrial arthropods helplessly struggle and are quickly eaten by aquatic predators. Exceptions to this outcome mostly occur among riparian taxa that escape by walking or swimming at the water surface. Here we document sustained, directional, neustonic locomotion (i.e. surface swimming) in tropical arboreal ants. We dropped 35 species of ants into natural and artificial aquatic settings in Peru and Panama to assess their swimming ability. Ten species showed directed surface swimming at speeds >3 body lengths s(-1), with some swimming at absolute speeds >10 cm s(-1). Ten other species exhibited partial swimming ability characterized by relatively slow but directed movement. The remaining species showed no locomotory control at the surface. The phylogenetic distribution of swimming among ant genera indicates parallel evolution and a trend toward negative association with directed aerial descent behavior. Experiments with workers of Odontomachus bauri showed that they escape from the water by directing their swimming toward dark emergent objects (i.e. skototaxis). Analyses of high-speed video images indicate that Pachycondyla spp. and O. bauri use a modified alternating tripod gait when swimming; they generate thrust at the water surface via synchronized treading and rowing motions of the contralateral fore and mid legs, respectively, while the hind legs provide roll stability. These results expand the list of facultatively neustonic terrestrial taxa to include various species of tropical arboreal ants. PMID:24920838

Yanoviak, S P; Frederick, D N

2014-06-15

259

What is ANTS? Focuses on those students  

E-print Network

What is ANTS? · Focuses on those students: · Returning to college after an interruption · Starting their college education later in life · Pursuing a career change · Juggling the demands of work- smoking facility. 3. No sleeping overnight or otherwise living in the office space is allowed. 4

New Mexico, University of

260

Competition and Coexistence of Larval Ant Lions  

Microsoft Academic Search

What factors permit the coexistence of competing species? In central Okla- homa, the predaceous ant lions Myrmeleon crudelis and M. immaculatus live in dense aggregations at the sheltered bases of cliff ledges. Three larval instars of each species act as predators and competitors of one another. In controlled field experiments, mortality of second and third instars increased with density, although

Nicholas J. Gotelli

1997-01-01

261

Resource redistribution in polydomous ant nest networks: local or global?  

PubMed Central

An important problem facing organisms in a heterogeneous environment is how to redistribute resources to where they are required. This is particularly complex in social insect societies as resources have to be moved both from the environment into the nest and between individuals within the nest. Polydomous ant colonies are split between multiple spatially separated, but socially connected, nests. Whether, and how, resources are redistributed between nests in polydomous colonies is unknown. We analyzed the nest networks of the facultatively polydomous wood ant Formica lugubris. Our results indicate that resource redistribution in polydomous F. lugubris colonies is organized at the local level between neighboring nests and not at the colony level. We found that internest trails connecting nests that differed more in their amount of foraging were stronger than trails between nests with more equal foraging activity. This indicates that resources are being exchanged directly from nests with a foraging excess to nests that require resources. In contrast, we found no significant relationships between nest properties, such as size and amount of foraging, and network measures such as centrality and connectedness. This indicates an absence of a colony-level resource exchange. This is a clear example of a complex behavior emerging as a result of local interactions between parts of a system. PMID:25214755

Franks, Daniel W.; Robinson, Elva J.H.

2014-01-01

262

The hyper-cube framework for ant colony optimization  

Microsoft Academic Search

Ant colony optimization is a metaheuristic approach belonging to the class of model-based search algorithms. In this paper, we propose a new framework for implementing ant colony optimization algorithms called the hyper-cube framework for ant colony optimization. In contrast to the usual way of implementing ant colony optimization algorithms, this framework limits the pheromone values to the interval [0,1]. This

Christian Blum; Marco Dorigo

2004-01-01

263

TermitAnt: An Ant Clustering Algorithm Improved by Ideas from Termite Colonies  

Microsoft Academic Search

\\u000a This paper proposes a heuristic to improve the convergence speed of the standard ant clustering algorithm. The heuristic is\\u000a based on the behavior of termites that, when building their nests, add some pheromone to the objects they carry. In this context,\\u000a pheromone allows artificial ants to get more information, at the local level, about the work in progress at the

Vahid Sherafat; Leandro Nunes De Castro; Eduardo R. Hruschka

2004-01-01

264

Can the Argentine ant ( Linepithema humile Mayr) replace native ants in myrmecochory?  

NASA Astrophysics Data System (ADS)

We analyse the influence of the Argentine ant ( Linepithema humile Mayr) on the seed dispersal process of the myrmecochorous plants Euphorbia characias, E. biumbellata, Genista linifolia, G. triflora, G. monspessulana and Sarothamnus arboreus. The observations were made in two study plots of Mediterranean cork-oak secondary forest (invaded and non-invaded by L. humile). The presence of L. humile implies the displacement of all native ant species that disperse seeds. Seed transports in the non-invaded zone were carried out by eight ant species. In the invaded zone, L. humile workers removed and transported seeds to the nest. In vertebrate exclusion trials, we observed the same level of seed removal in the invaded and non-invaded zones. Two findings could explain this result. Although mean time to seed localization was higher for native ants (431.7 s) than that for L. humile (150.5 s), the mean proportion of seeds transported after being detected was higher (50.1%) in non-invaded than in invaded (16.8%) zones. The proportion of seeds removed and transported into an ant nest after an ant-seed interaction had dramatically reduced from non-invaded (41.9%) to invaded (7.4%) zones. The levels of seed dispersal by ants found prior to invasion are unlikely to be maintained in invaded zones. However, total replacement of seed dispersal function is possible if contact iteration finally offers similar levels or quantities of seeds reaching the nests. The results obtained confirm that the Argentine ant invasion may affect myrmecochory dramatically in the Mediterranean biome.

Gómez, Crisanto; Oliveras, Jordi

2003-04-01

265

Structural and Molecular Basis for Resistance to Aminoglycoside Antibiotics by the Adenylyltransferase ANT(2?)-Ia  

PubMed Central

ABSTRACT ? The aminoglycosides are highly effective broad-spectrum antimicrobial agents. However, their efficacy is diminished due to enzyme-mediated covalent modification, which reduces affinity of the drug for the target ribosome. One of the most prevalent aminoglycoside resistance enzymes in Gram-negative pathogens is the adenylyltransferase ANT(2?)-Ia, which confers resistance to gentamicin, tobramycin, and kanamycin. Despite the importance of this enzyme in drug resistance, its structure and molecular mechanism have been elusive. This study describes the structural and mechanistic basis for adenylylation of aminoglycosides by the ANT(2?)-Ia enzyme. ANT(2?)-Ia confers resistance by magnesium-dependent transfer of a nucleoside monophosphate (AMP) to the 2?-hydroxyl of aminoglycoside substrates containing a 2-deoxystreptamine core. The catalyzed reaction follows a direct AMP transfer mechanism from ATP to the substrate antibiotic. Central to catalysis is the coordination of two Mg2+ ions, positioning of the modifiable substrate ring, and the presence of a catalytic base (Asp86). Comparative structural analysis revealed that ANT(2?)-Ia has a two-domain structure with an N-terminal active-site architecture that is conserved among other antibiotic nucleotidyltransferases, including Lnu(A), LinB, ANT(4?)-Ia, ANT(4?)-Ib, and ANT(6)-Ia. There is also similarity between the nucleotidyltransferase fold of ANT(2?)-Ia and DNA polymerase ?. This similarity is consistent with evolution from a common ancestor, with the nucleotidyltransferase fold having adapted for activity against chemically distinct molecules. Importance ? To successfully manage the threat associated with multidrug-resistant infectious diseases, innovative therapeutic strategies need to be developed. One such approach involves the enhancement or potentiation of existing antibiotics against resistant strains of bacteria. The reduction in clinical usefulness of the aminoglycosides is a particular problem among Gram-negative human pathogens, since there are very few therapeutic options for infections caused by these organisms. In order to successfully circumvent or inhibit the activity of aminoglycoside-modifying enzymes, and to thus rejuvenate the activity of the aminoglycoside antibiotics against Gram-negative pathogens, structural and mechanistic information is crucial. This study reveals the structure of a clinically prevalent aminoglycoside resistance enzyme [ANT(2?)-Ia] and depicts the molecular basis underlying modification of antibiotic substrates. Combined, these findings provide the groundwork for the development of broad-spectrum inhibitors against antibiotic nucleotidyltransferases. PMID:25564464

Cox, Georgina; Stogios, Peter J.; Savchenko, Alexei

2015-01-01

266

Structural and Molecular Basis for Resistance to Aminoglycoside Antibiotics by the Adenylyltransferase ANT(2?)-Ia.  

PubMed

The aminoglycosides are highly effective broad-spectrum antimicrobial agents. However, their efficacy is diminished due to enzyme-mediated covalent modification, which reduces affinity of the drug for the target ribosome. One of the most prevalent aminoglycoside resistance enzymes in Gram-negative pathogens is the adenylyltransferase ANT(2?)-Ia, which confers resistance to gentamicin, tobramycin, and kanamycin. Despite the importance of this enzyme in drug resistance, its structure and molecular mechanism have been elusive. This study describes the structural and mechanistic basis for adenylylation of aminoglycosides by the ANT(2?)-Ia enzyme. ANT(2?)-Ia confers resistance by magnesium-dependent transfer of a nucleoside monophosphate (AMP) to the 2?-hydroxyl of aminoglycoside substrates containing a 2-deoxystreptamine core. The catalyzed reaction follows a direct AMP transfer mechanism from ATP to the substrate antibiotic. Central to catalysis is the coordination of two Mg(2+) ions, positioning of the modifiable substrate ring, and the presence of a catalytic base (Asp86). Comparative structural analysis revealed that ANT(2?)-Ia has a two-domain structure with an N-terminal active-site architecture that is conserved among other antibiotic nucleotidyltransferases, including Lnu(A), LinB, ANT(4')-Ia, ANT(4?)-Ib, and ANT(6)-Ia. There is also similarity between the nucleotidyltransferase fold of ANT(2?)-Ia and DNA polymerase ?. This similarity is consistent with evolution from a common ancestor, with the nucleotidyltransferase fold having adapted for activity against chemically distinct molecules. IMPORTANCE ?: To successfully manage the threat associated with multidrug-resistant infectious diseases, innovative therapeutic strategies need to be developed. One such approach involves the enhancement or potentiation of existing antibiotics against resistant strains of bacteria. The reduction in clinical usefulness of the aminoglycosides is a particular problem among Gram-negative human pathogens, since there are very few therapeutic options for infections caused by these organisms. In order to successfully circumvent or inhibit the activity of aminoglycoside-modifying enzymes, and to thus rejuvenate the activity of the aminoglycoside antibiotics against Gram-negative pathogens, structural and mechanistic information is crucial. This study reveals the structure of a clinically prevalent aminoglycoside resistance enzyme [ANT(2?)-Ia] and depicts the molecular basis underlying modification of antibiotic substrates. Combined, these findings provide the groundwork for the development of broad-spectrum inhibitors against antibiotic nucleotidyltransferases. PMID:25564464

Cox, Georgina; Stogios, Peter J; Savchenko, Alexei; Wright, Gerard D

2015-01-01

267

HOUSEHOLD AND STRUCTURAL INSECTS Trap-Mulching Argentine Ants  

E-print Network

HOUSEHOLD AND STRUCTURAL INSECTS Trap-Mulching Argentine Ants JULES SILVERMAN,1 CLYDE E. SORENSON. Econ. Entomol. 99(5): 1757Ð1760 (2006) ABSTRACT Argentine ant, Linepithema humile (Mayr), management ants are repelled from a broad domain of nest sites to smaller de�ned areas, which are subsequently

Buckel, Jeffrey A.

268

Model Specification Searches Using Ant Colony Optimization Algorithms  

ERIC Educational Resources Information Center

Ant colony optimization is a recently proposed heuristic procedure inspired by the behavior of real ants. This article applies the procedure to model specification searches in structural equation modeling and reports the results. The results demonstrate the capabilities of ant colony optimization algorithms for conducting automated searches.

Marcoulides, George A.; Drezner, Zvi

2003-01-01

269

CHECK LIST OF THE ANTS (HYMENOPTERA: FORMICIDJ2) OF ASIA  

E-print Network

#12;#12;#12;#12;CHECK LIST OF THE ANTS (HYMENOPTERA: FORMICIDJ2) OF ASIA JAMES W. CHAPMAN Formerly of the senior author's ant collection was still in Dumaguete, though a great deal had been sent to Dr. W. M. The ant literature, records of some twenty- live years collecting, card catalogue, and an incomplete draft

Villemant, Claire

270

Ants as Naturally Long-lived Insect Models for Aging.  

E-print Network

Ants as Naturally Long-lived Insect Models for Aging. Joel D. Parker and Karen M. Parker Department.Parker@unil.ch Karen.Parker@unil.ch #12;Scope and Purpose This chapter explains in what respects ants can be useful models in understanding the mechanisms of aging. It includes an introduction highlighting how ants

Alvarez, Nadir

271

Ant Algorithms and Generalized Finite Urns Christopher Leith  

E-print Network

Ant Algorithms and Generalized Finite Urns by Christopher Leith A thesis submitted behaviour of pheromone trail laying biological agents. These ant algorithms, as they are commonly called system. Our interest lies mainly with the latter application. Analyzing the effectiveness of ant

Linder, Tamás

272

New records of ants (Hymenoptera: Formicidae) OMID PAKNIA1  

E-print Network

New records of ants (Hymenoptera: Formicidae) from Iran OMID PAKNIA1 ,ALEXANDER RADCHENKO2's email: omid.paknia@uni-ulm.de ABSTRACT. The ant species list of Iran is far from complete. So far, only the majority of ant material in two periods of field work in spring and summer of 2007 and 2008. In total, we

Villemant, Claire

273

Dynamics of an ant-plant-pollinator model  

NASA Astrophysics Data System (ADS)

In this paper, we consider plant-pollinator-ant systems in which plant-pollinator interaction and plant-ant interaction are both mutualistic, but there also exists interference of pollinators by ants. The plant-pollinator interaction can be described by a Beddington-DeAngelis formula, so we extend the formula to characterize plant-pollinator mutualisms, including the interference by ants, and form a plant-pollinator-ant model. Using dynamical systems theory, we show uniform persistence of the model. Moreover, we demonstrate conditions under which boundary equilibria are globally asymptotically stable. The dynamics exhibit mechanisms by which the three species could coexist when ants interfere with pollinators. We define a threshold in ant interference. When ant interference is strong, it can drive plant-pollinator mutualisms to extinction. Furthermore, if the ants depend on pollination mutualism for their persistence, then sufficiently strong ant interference could lead to their own extinction as well. Yet, when ant interference is weak, plant-ant and plant-pollinator mutualisms can promote the persistence of one another.

Wang, Yuanshi; DeAngelis, Donald L.; Nathaniel Holland, J.

2015-03-01

274

Do Desert Ants Use Partial Image Matching for Landmark Navigation?  

E-print Network

Do Desert Ants Use Partial Image Matching for Landmark Navigation? Ralf Moller1;2 , Dimitrios University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland Desert ants (genus Cataglyphis) have of Experimental Biology, 199:129{140, 1996. 3] R. Wehner and F. Raber. Visual spatial memory in desert ants

Moeller, Ralf

275

Arboreal ant diversity (Hymenoptera: Formicidae) in a central African forest  

Microsoft Academic Search

Like many developing tropical areas, central Africa is subject to substantial anthropogenic disturbance associ- ated with the large-scale harvesting of natural resources. We surveyed the ants of the forest canopy at an oil extraction site near Gamba, Gabon. Ants were collected by hand and with tuna baits from nine tree crowns in late secondary forest. Thirty-six ant species were collected

S. P. Yanoviak; B. L. Fisher; A. Alonso

2007-01-01

276

Competition between harvester ants and rodents in the cold desert  

Microsoft Academic Search

Local distribution patterns of three rodent species (Perognathus parvus, Peromyscus maniculatus, Reithrodontomys megalotis) were studied in areas of high and low densities of harvester ants (Pogonomyrmex owyheei) in Raft River Valley, Idaho. Numbers of rodents were greatest in areas of high ant-density during May, but partially reduced in August; whereas, the trend was reversed in areas of low ant-density. Seed

D. S. Landeen; C. D. Jorgensen; H. D. Smith

1979-01-01

277

Trail pheromone disruption of red imported fire ant  

Technology Transfer Automated Retrieval System (TEKTRAN)

The fire ant, Solenopsis invicta, is one of the most aggressive and invasive species in the world but toxic bait systems affect non-target ant species and can not be used in sensitive ecosystems. The fire ant uses recruitment pheromones to organize the retrieval of food resources back to the colony....

278

Millipede Defense: Use of Detachable Bristles to Entangle Ants  

Microsoft Academic Search

The millipede Polyxenus fasciculatus (Diplopoda; Polyxenida) defends itself against ants by use of a pair of bristle tufts at its rear. When attacked, it wipes the tufts against the ants, thereby causing these to become encumbered by bristles that detach from the tufts. Ants contaminated with bristles desist from their assault. The bristles have grappling hooks at the tip by

Thomas Eisner; Maria Eisner; Mark Deyrup

1996-01-01

279

Is extrafloral nectar production induced by herbivores or ants in a tropical facultative ant-plant mutualism?  

E-print Network

Is extrafloral nectar production induced by herbivores or ants in a tropical facultative ant-plant of the plants to respond as the plants in this study increased nectar production in11 response to light and ant.bixenmann@utah.edu 2­Dept.ofBiology,UniversityofUtah SaltLakeCity,UT841120840,USA #12; Abstract1 Many plants use

Coley, Phyllis

280

Harvester ant bioassay for assessing hazardous chemical waste sites  

SciTech Connect

A technique was developed for using harvester ants, Pogonomyrmex owhyeei, in terrestrial bioassays. Procedures were developed for maintaining stock populations, handling ants, and exposing ants to toxic materials. Relative toxicities were determined by exposing ants to 10 different materials. These materials included three insecticides, Endrin, Aldrin, and Dieldrin; one herbicide, 2,4-D; three oil-like compounds, wood preservative, drilling fluid, and slop oil; and three heavy metals, copper, zinc, and cadmium. Ants were exposed in petri dishes containing soil amended with a particular toxicant. Under these test conditions, ants showed no sensitivity to the metals or 2,4-D. Ants were sensitive to the insecticides and oils in repeated tests, and relative toxicity remained consistent throughout. Aldrin was the most toxic material, followed by Dieldrin, Endrin, wood preservative, drilling fluid, and slop oil. 10 refs., 2 figs., 2 tabs.

Gano, K.A.; Carlile, D.W.; Rogers, L.E.

1984-12-01

281

Fast and Flexible: Argentine Ants Recruit from Nearby Trails  

PubMed Central

Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources. PMID:23967129

Flanagan, Tatiana P.; Pinter-Wollman, Noa M.; Moses, Melanie E.; Gordon, Deborah M.

2013-01-01

282

USDA: FORMIS: A Master Bibliography of Ant Literature  

NSDL National Science Digital Library

Hosted by the USDA's Center for Medical, Agricultural, and Veterinary Entomology, this Master Bibliography of Ant Literature, entitled FORMIS, "is a composite of several ant literature databases. It contains citations for a large fraction of the world's ant literature (about 32,000 references). FORMIS contains all known ant taxonomic literature (through 1996)." In addition, FORMIS features comprehensive bibliographies of fire ants, Russian wood ants, and leaf-cutting ants. The website offers options for online searches and downloads. The site was last modified in April 2004; however, it should be noted that FORMIS has not been updated since 2003, thus users should not expect to find the most recent literature. Despite the lack of up-to-date literature, FORMIS remains a substantial resource for myrmecologists and other researchers. Furthermore, the editors are requesting assistance for the continued expansion and updating of FORMIS.

283

Exploring with PAM: Prospecting ANTS Missions for Solar System Surveys  

NASA Technical Reports Server (NTRS)

ANTS (Autonomous Nano-Technology Swarm), a large (1000 member) swarm of nano to picoclass (10 to 1 kg) totally autonomous spacecraft, are being developed as a NASA advanced mission concept. ANTS, based on a hierarchical insect social order, use an evolvable, self-similar, hierarchical neural system in which individual spacecraft represent the highest level nodes. ANTS uses swarm intelligence attained through collective, cooperative interactions of the nodes at all levels of the system. At the highest levels this can take the form of cooperative, collective behavior among the individual spacecraft in a very large constellation. The ANTS neural architecture is designed for totally autonomous operation of complex systems including spacecraft constellations. The ANTS (Autonomous Nano Technology Swarm) concept has a number of possible applications. A version of ANTS designed for surveying and determining the resource potential of the asteroid belt, called PAM (Prospecting ANTS Mission), is examined here.

Clark, P. E.; Rilee, M. L.; Curtis, S. A.

2003-01-01

284

Parallel Ant-Miner (PAM) on High Performance Clusters  

NASA Astrophysics Data System (ADS)

This study implements parallelization of Ant-Miner for classification rules discovery. Ant-Miner code is parallelized and optimized in a cluster environment by employing master-slave model. The parallelization is achieved in two different operations of Ant-Miner viz. discretization of continuous attributes and rule construction by ants. For rule mining operation, ants are equally distributed into groups and sent across the different cluster nodes. The performance study of Parallel Ant-Miner (PAM) employs different publicly available datasets. The results indicate remarkable improvement in computational time without compromising on the classification accuracy and quality of discovered rules. Dermatology data having 33 features and musk data having 168 features were taken to study performance with respect to timings. Speedup almost equivalent to ideal speedup was obtained on 8 CPUs with increase in number of features and number of ants. Also performance with respect to accuracies was done using lung cancer data.

Chintalapati, Janaki; Arvind, M.; Priyanka, S.; Mangala, N.; Valadi, Jayaraman

285

Optic disc detection using ant colony optimization  

NASA Astrophysics Data System (ADS)

The retinal fundus images are used in the treatment and diagnosis of several eye diseases, such as diabetic retinopathy and glaucoma. This paper proposes a new method to detect the optic disc (OD) automatically, due to the fact that the knowledge of the OD location is essential to the automatic analysis of retinal images. Ant Colony Optimization (ACO) is an optimization algorithm inspired by the foraging behaviour of some ant species that has been applied in image processing for edge detection. Recently, the ACO was used in fundus images to detect edges, and therefore, to segment the OD and other anatomical retinal structures. We present an algorithm for the detection of OD in the retina which takes advantage of the Gabor wavelet transform, entropy and ACO algorithm. Forty images of the retina from DRIVE database were used to evaluate the performance of our method.

Dias, Marcy A.; Monteiro, Fernando C.

2012-09-01

286

The Ants: A Community of Microrobots  

NSDL National Science Digital Library

A community of cubic-inch microrobots called "ants" is located at the Massachusetts Institute of Technology artificial intelligence laboratory. As part of a larger initiative to develop technologies for planetary exploration, the two main goals of the Ants project are "to push the limit of microrobotics by integrating many sensors and actuators into a small package, and to form a structured robotic community from the interactions of many simple individuals." Information pertaining to topics such as Hardware, Software, Related Research at the MIT AI Lab, Related Research Elsewhere, and Related Web Sites is listed under these subheadings. At the Website, the user will also find links to related MIT project sites such as Explosive Ordnance Disposal and Mars Exploration. These projects are an example of the many applications of robotic communities.

287

Microfungal “Weeds” in the Leafcutter Ant Symbiosis  

Microsoft Academic Search

Leafcutter ants (Formicidae: tribe Attini) are well-known insects that cultivate basidiomycete fungi (Agaricales: Lepiotaceae)\\u000a as their principal food. Fungus gardens are monocultures of a single cultivar strain, but they also harbor a diverse assemblage\\u000a of additional microbes with largely unknown roles in the symbiosis. Cultivar-attacking microfungi in the genus Escovopsis are specialized parasites found only in association with attine gardens.

A. Rodrigues; M. Bacci Jr; U. G. Mueller; A. Ortiz; F. C. Pagnocca

2008-01-01

288

Biomimicry: Further Insights from Ant Colonies?  

Microsoft Academic Search

Biomimicry means learning from nature. Well known examples include physical structures such as the Velcro fastener. But natural\\u000a selection has also “engineered” mechanisms by which the components of adaptive biological systems are organized. For example,\\u000a natural selection has caused the foragers in an ant colony to cooperate and communicate in order to increase the total foraging\\u000a success of the colony.

Francis L. W. Ratnieks

2007-01-01

289

Managing Imported Fire Ants in Urban Areas  

E-print Network

out- weigh any benefits in urban areas. While it may not be possible to eradicate fire ants, controlling them is highly desirable. The best control programs use a combination of non-chemical and chemical meth- ods that are effective, economical... granules, granules drenched with water after applica- tion, liquid drenches, baits, or aerosol injec- tions. Non-chemical treatment methods such as drenching mounds with very hot water also may be used. Mound treatments may need to be repeated...

Drees, Bastiaan M.

2006-08-17

290

Polydomy in the ant Ectatomma opaciventre  

PubMed Central

Tropical ants commonly exhibit a hyper-dispersed pattern of spatial distribution of nests. In polydomous species, nests may be satellites, that is, secondary structures of the main nest, where the queen is found. In order to evaluate whether the ant Ectatomma opaciventre Roger (Formicidae: Ectatomminae) uses the strategy of building polydomous nests, the spatial distribution pattern of 33 nests in a 1,800 m2 degraded area located in Rio Claro, SP, Brazil, were investigated using the nearest neighbor method. To complement the results of this investigation, the cuticular chemical profile of eight colonies was analyzed using Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS). The nests of E. opaciventre presented a hyper-dispersed or regular distribution, which is the most common in ants. The analysis of the cuticular hydrocarbons apparently confirmed the hypothesis that this species is polydomous, since the chemical profiles of all studied colonies with nests at different sites were very similar to the chemical signature of the single found queen and were also different from those of colonies used as control. PMID:25373168

Tofolo, Viviane C.; Giannotti, Edilberto; Neves, Erika F.; Andrade, Luis H. C.; Lima, Sandro M.; Súarez, Yzel R.; Antonialli-Junior, William F.

2014-01-01

291

Relative effects of disturbance on red imported fire ants and native ant species in a longleaf pine ecosystem.  

PubMed

The degree to which changes in community composition mediate the probability of colonization and spread of non-native species is not well understood, especially in animal communities. High species richness may hinder the establishment of non-native species. Distinguishing between this scenario and cases in which non-native species become established in intact (lacking extensive anthropogenic soil disturbance) communities and subsequently diminish the abundance and richness of native species is challenging on the basis of observation alone. The red imported fire ant (Solenopsis invicta), an invasive species that occurs throughout much of the southeastern United States, is such an example. Rather than competitively displacing native species, fire ants may become established only in disturbed areas in which native species richness and abundance are already reduced. We used insecticide to reduce the abundance of native ants and fire ants in four experimental plots. We then observed the reassembly and reestablishment of the ants in these plots for 1 year after treatment. The abundance of fire ants in treated plots did not differ from abundance in control plots 1 year after treatment. Likewise, the abundance of native ants increased to levels comparable to those in control plots after 1 year. Our findings suggest that factors other than large reductions in ant abundance and species density (number of species per unit area) may affect the establishment of fire ants and that the response of native ants and fire ants to disturbance can be comparable. PMID:21561472

Stuble, Katharine L; Kirkman, L Katherine; Carroll, C Ronald; Sanders, Nathan J

2011-06-01

292

Design of FIR Filters with Discrete Coefficients using Ant Colony Optimization  

NASA Astrophysics Data System (ADS)

In this paper, we propose a new design method for linear phase FIR (Finite Impulse Response) filters with discrete coefficients. In a hardware implementation, filter coefficients must be represented as discrete values. The design problem of digital filters with discrete coefficients is formulated as the integer programming problem. Then, an enormous amount of computational time is required to solve the problem in a strict solver. Recently, ACO (Ant Colony Optimization) which is one heuristic approach, is used widely for solving combinational problem like the traveling salesman problem. In our method, we formulate the design problem as the 0-1 integer programming problem and solve it by using the ACO. Several design examples are shown to present effectiveness of the proposed method.

Tsutsumi, Shuntaro; Suyama, Kenji

293

Scope of Various Random Number Generators in Ant System Approach for TSP  

NASA Technical Reports Server (NTRS)

Experimented on heuristic, based on an ant system approach for traveling Salesman problem, are several quasi and pseudo-random number generators. This experiment is to explore if any particular generator is most desirable. Such an experiment on large samples has the potential to rank the performance of the generators for the foregoing heuristic. This is just to seek an answer to the controversial performance ranking of the generators in probabilistic/statically sense.

Sen, S. K.; Shaykhian, Gholam Ali

2007-01-01

294

Isolating antifungals from fungus-growing ant symbionts using a genome-guided chemistry approach.  

PubMed

We describe methods used to isolate and identify antifungal compounds from actinomycete strains associated with the leaf-cutter ant Acromyrmex octospinosus. These ants use antibiotics produced by symbiotic actinomycete bacteria to protect themselves and their fungal cultivar against bacterial and fungal infections. The fungal cultivar serves as the sole food source for the ant colony, which can number up to tens of thousands of individuals. We describe how we isolate bacteria from leaf-cutter ants collected in Trinidad and analyze the antifungal compounds made by two of these strains (Pseudonocardia and Streptomyces spp.), using a combination of genome analysis, mutagenesis, and chemical isolation. These methods should be generalizable to a wide variety of insect-symbiont situations. Although more time consuming than traditional activity-guided fractionation methods, this approach provides a powerful technique for unlocking the complete biosynthetic potential of individual strains and for avoiding the problems of rediscovery of known compounds. We describe the discovery of a novel nystatin compound, named nystatin P1, and identification of the biosynthetic pathway for antimycins, compounds that were first described more than 60 years ago. We also report that disruption of two known antifungal pathways in a single Streptomyces strain has revealed a third, and likely novel, antifungal plus four more pathways with unknown products. This validates our approach, which clearly has the potential to identify numerous new compounds, even from well-characterized actinomycete strains. PMID:23084933

Seipke, Ryan F; Grüschow, Sabine; Goss, Rebecca J M; Hutchings, Matthew I

2012-01-01

295

Ant Colony Optimization Analysis on Overall Stability of High Arch Dam Basis of Field Monitoring  

PubMed Central

A dam ant colony optimization (D-ACO) analysis of the overall stability of high arch dams on complicated foundations is presented in this paper. A modified ant colony optimization (ACO) model is proposed for obtaining dam concrete and rock mechanical parameters. A typical dam parameter feedback problem is proposed for nonlinear back-analysis numerical model based on field monitoring deformation and ACO. The basic principle of the proposed model is the establishment of the objective function of optimizing real concrete and rock mechanical parameter. The feedback analysis is then implemented with a modified ant colony algorithm. The algorithm performance is satisfactory, and the accuracy is verified. The m groups of feedback parameters, used to run a nonlinear FEM code, and the displacement and stress distribution are discussed. A feedback analysis of the deformation of the Lijiaxia arch dam and based on the modified ant colony optimization method is also conducted. By considering various material parameters obtained using different analysis methods, comparative analyses were conducted on dam displacements, stress distribution characteristics, and overall dam stability. The comparison results show that the proposal model can effectively solve for feedback multiple parameters of dam concrete and rock material and basically satisfy assessment requirements for geotechnical structural engineering discipline. PMID:25025089

Liu, Xiaoli; Chen, Hong-Xin; Kim, Jinxie

2014-01-01

296

AntCast: Web-Window on the Life of Ants  

NSDL National Science Digital Library

The leafcutter ant colony at London's Natural History Museum is now live on the Web, "using an infrared camera to give a secret view into the lives of these fascinating creatures. Visitors can view live video or static images of the colony as they tend to their fungus farm. Only ten users at a time can view the live video, but the static images are updated every ten seconds, so no need feel too deprived. The images are accompanied by interesting ant facts, but for more detailed information visitors will have to look elsewhere.

297

Ant tending influences soldier production in a social aphid.  

PubMed Central

The aphid Pseudoregma sundanica (Van der Goot) (Homoptera: Aphididae) has two defence strategies. It is obligatorily tended by various species of ant and also produces sterile soldiers. We investigated how they allocate their investment in these two strategies. We measured the size, number of soldiers, number and species of tending ant, and number and species of predators in P. sundanica populations. We found that the level of ant tending correlated negatively with soldier investment in P. sundanica. The species of tending ant also influenced soldier investment. We excluded ants from aphid populations and recorded changes in population size and structure over four weeks. Ant exclusion led to population decline and extinction. At the same time, surviving populations showed a significant increase in soldier investment. The data demonstrate that social aphids can adjust their investment in soldiers in direct response to environmental change. PMID:11052537

Shingleton, A W; Foster, W A

2000-01-01

298

Improved multi-objective ant colony optimization algorithm and its application in complex reasoning  

NASA Astrophysics Data System (ADS)

The problem of fault reasoning has aroused great concern in scientific and engineering fields. However, fault investigation and reasoning of complex system is not a simple reasoning decision-making problem. It has become a typical multi-constraint and multi-objective reticulate optimization decision-making problem under many influencing factors and constraints. So far, little research has been carried out in this field. This paper transforms the fault reasoning problem of complex system into a paths-searching problem starting from known symptoms to fault causes. Three optimization objectives are considered simultaneously: maximum probability of average fault, maximum average importance, and minimum average complexity of test. Under the constraints of both known symptoms and the causal relationship among different components, a multi-objective optimization mathematical model is set up, taking minimizing cost of fault reasoning as the target function. Since the problem is non-deterministic polynomial-hard(NP-hard), a modified multi-objective ant colony algorithm is proposed, in which a reachability matrix is set up to constrain the feasible search nodes of the ants and a new pseudo-random-proportional rule and a pheromone adjustment mechinism are constructed to balance conflicts between the optimization objectives. At last, a Pareto optimal set is acquired. Evaluation functions based on validity and tendency of reasoning paths are defined to optimize noninferior set, through which the final fault causes can be identified according to decision-making demands, thus realize fault reasoning of the multi-constraint and multi-objective complex system. Reasoning results demonstrate that the improved multi-objective ant colony optimization(IMACO) can realize reasoning and locating fault positions precisely by solving the multi-objective fault diagnosis model, which provides a new method to solve the problem of multi-constraint and multi-objective fault diagnosis and reasoning of complex system.

Wang, Xinqing; Zhao, Yang; Wang, Dong; Zhu, Huijie; Zhang, Qing

2013-09-01

299

Optimal Screening Policies for Diabetic Retinopathy Using a Combined Discrete-Event Simulation and Ant Colony Optimization Approach  

Microsoft Academic Search

In this paper, we present the first published healthcare application of discrete-event simulation embedded in an ant colony optimization model. We consider the problem of choosing optimal screening policies for retinopathy, a serious complication of diabetes. In order to minimize the screening cost per year of sight saved, compared with a situation with no screening, individuals aged between 30 and

Marion S. Rauner; Walter J. Gutjahr; Sally C. Brailsford; Wolfgang Zeppelzauer

300

Optimizing expressway maintenance planning by coupling ant algorithm and geography information system transportation in Hubei province, China  

Microsoft Academic Search

Highway maintenance scheduling is a complex optimization problem and imposes a challenge for GIS-T research. In this paper, a new approach was put forward to determining the optimal set of alternatives for highway infrastructure facilities by using ant colony algorithm and GIS. In the proposed approach, GIS was used to analyze traffic flux, toll and maintenance time of each highway

Hongga Li; Xiaoxia Huang; Quan Feng

2011-01-01

301

Broadcast Baits for Fire Ant Control  

E-print Network

ingredients have different modes of action, they all serve to break the life cycle of the colony, resulting in its death. Fast-acting baits actually kill the queen and, to varying degrees, worker ants. Baits containing insect growth regulators (IGR) do... bait treatment Most broadcast baits work more slowly than do contact insecticides, though a few work just as fast. There is a trade-off, though: The faster a bait works, the sooner the area is open for reinvasion. With any broadcast bait, you should...

Barr, Charles L.

2005-10-17

302

Weeding and grooming of pathogens in agriculture by ants  

Microsoft Academic Search

The ancient mutualism between fungus-growing ants and the fungi they cultivate for food is a textbook example of symbiosis. Fungus-growing ants'ability to cultivate fungi depends on protection of the garden from the aggressive microbes associated with the substrate added to the garden as well as from the specialized virulent garden parasite Escovopsis. We examined ants' ability to remove alien microbes

Cameron R. Currie; Alison E. Stuart

2001-01-01

303

Directed Aerial Descent Behavior in African Canopy Ants (Hymenoptera: Formicidae)  

Microsoft Academic Search

Several species of neotropical ants direct their aerial descent toward tree trunks during a fall from the forest canopy. The\\u000a primary goal of this study was to determine if afrotropical arboreal ants exhibit similar gliding behavior. Ants were collected\\u000a from nine tree crowns in late secondary forest at a hydrocarbon extraction site near Gamba, Gabon. Of the 32 species tested,

S. P. Yanoviak; B. L. Fisher; A. Alonso

2008-01-01

304

Do Herbivores Eavesdrop on Ant Chemical Communication to Avoid Predation?  

PubMed Central

Strong effects of predator chemical cues on prey are common in aquatic and marine ecosystems, but are thought to be rare in terrestrial systems and specifically for arthropods. For ants, herbivores are hypothesized to eavesdrop on ant chemical communication and thereby avoid predation or confrontation. Here I tested the effect of ant chemical cues on herbivore choice and herbivory. Using Margaridisa sp. flea beetles and leaves from the host tree (Conostegia xalapensis), I performed paired-leaf choice feeding experiments. Coating leaves with crushed ant liquids (Azteca instabilis), exposing leaves to ant patrolling prior to choice tests (A. instabilis and Camponotus textor) and comparing leaves from trees with and without A. instabilis nests resulted in more herbivores and herbivory on control (no ant-treatment) relative to ant-treatment leaves. In contrast to A. instabilis and C. textor, leaves previously patrolled by Solenopsis geminata had no difference in beetle number and damage compared to control leaves. Altering the time A. instabilis patrolled treatment leaves prior to choice tests (0-, 5-, 30-, 90-, 180-min.) revealed treatment effects were only statistically significant after 90- and 180-min. of prior leaf exposure. This study suggests, for two ecologically important and taxonomically diverse genera (Azteca and Camponotus), ant chemical cues have important effects on herbivores and that these effects may be widespread across the ant family. It suggests that the effect of chemical cues on herbivores may only appear after substantial previous ant activity has occurred on plant tissues. Furthermore, it supports the hypothesis that herbivores use ant chemical communication to avoid predation or confrontation with ants. PMID:22235248

Gonthier, David J.

2012-01-01

305

Integrating Lookahead and Post Processing Procedures with ACO for Solving Set Partitioning and Covering Problems  

Microsoft Academic Search

Set Covering Problems and Set Partitioning Problems can model several real life situations. In this paper, we solve some bench- marks of them with Ant Colony Optimization algorithms and some hy- bridizations of Ant Colony Optimization with Constraint Programming techniques. A lookahead mechanism allows the incorporation of informa- tion on the anticipated decisions that are beyond the immediate choice horizon.

Broderick Crawford; Carlos Castro

2006-01-01

306

Ant-aphid mutualisms: the impact of honeydew production and honeydew sugar composition on ant preferences  

Microsoft Academic Search

The honeydew composition and production of four aphid species feeding on Tanacetum vulgare, and mutualistic relationships with the ant Lasius niger were studied. In honeydew of Metopeurum fuscoviride and Brachycaudus cardui, xylose, glucose, fructose, sucrose, maltose, melezitose, and raffinose were detected. The proportion of trisaccharides (melezitose,\\u000a raffinose) ranged between 20% and 35%. No trisaccharides were found in honeydew of Aphis

Wolfgang Völkl; Joseph Woodring; Melanie Fischer; Matthias W. Lorenz; Klaus H. Hoffmann

1999-01-01

307

Signals Can Trump Rewards in Attracting Seed-Dispersing Ants  

PubMed Central

Both rewards and signals are important in mutualisms. In myrmecochory, or seed dispersal by ants, the benefits to plants are relatively well studied, but less is known about why ants pick up and move seeds. We examined seed dispersal by the ant Aphaenogaster rudis of four co-occurring species of plants, and tested whether morphology, chemical signaling, or the nutritional quality of fatty seed appendages called elaiosomes influenced dispersal rates. In removal trials, ants quickly collected diaspores (seeds plus elaiosomes) of Asarum canadense, Trillium grandiflorum, and Sanguinaria canadensis, but largely neglected those of T. erectum. This discrepancy was not explained by differences in the bulk cost-benefit ratio, as assessed by the ratio of seed to elaiosome mass. We also provisioned colonies with diaspores from one of these four plant species or no diaspores as a control. Colonies performed best when fed S. canadensis diaspores, worst when fed T. grandiflorum, and intermediately when fed A. canadense, T. erectum, or no diaspores. Thus, the nutritional rewards in elaiosomes affected colony performance, but did not completely predict seed removal. Instead, high levels of oleic acid in T. grandiflorum elaiosomes may explain why ants disperse these diaspores even though they reduce ant colony performance. We show for the first time that different elaiosome-bearing plants provide rewards of different quality to ant colonies, but also that ants appear unable to accurately assess reward quality when encountering seeds. Instead, we suggest that signals can trump rewards as attractants of ants to seeds. PMID:23967257

Turner, Kyle M.; Frederickson, Megan E.

2013-01-01

308

Evolution and ecology of directed aerial descent in arboreal ants.  

PubMed

Directed aerial descent (DAD) is used by a variety of arboreal animals to escape predators, to remain in the canopy, and to access resources. Here, we build upon the discovery of DAD in ants of tropical canopies by summarizing its known phylogenetic distribution among ant genera, and within both the subfamily Pseudomyrmecinae and the genus Cephalotes. DAD has multiple evolutionary origins in ants, occurring independently in numerous genera in the subfamilies Myrmicinae, Formicinae, and Pseudomyrmecinae. Ablation experiments and video recordings of ants in a vertical wind tunnel showed that DAD in Cephalotes atratus is achieved via postural changes, specifically orientation of the legs and gaster. The occurrence of DAD in Formicinae indicates that the presence of a postpetiole is not essential for the behavior. Evidence to date indicates that gliding behavior is accomplished by visual targeting mediated by the compound eyes, and is restricted to diurnally active ants that nest in trees. Occlusion of ocelli in Pseudomyrmex gracilis workers had no effect on their success or performance in gliding. Experimental assessment of the fate of ants that fall to the understory showed that ants landing in water are 15 times more likely to suffer lethal attacks than are ants landing in leaf litter. Variation in both the aerodynamic mechanisms and selective advantages of DAD merits further study given the broad taxonomic diversity of arboreal ants that engage in this intriguing form of flight. PMID:21562023

Yanoviak, Stephen P; Munk, Yonatan; Dudley, Robert

2011-12-01

309

Mapping lessons from ants to free flight: an ant-based weather avoidance algorithm in free flight airspace  

NASA Astrophysics Data System (ADS)

The continuing growth of air traffic worldwide motivates the need for new approaches to air traffic management that are more flexible both in terms of traffic volume and weather. Free Flight is one such approach seriously considered by the aviation community. However the benefits of Free Flight are severely curtailed in the convective weather season when weather is highly active, leading aircrafts to deviate from their optimal trajectories. This paper investigates the use of ant colony optimization in generating optimal weather avoidance trajectories in Free Flight airspace. The problem is motivated by the need to take full advantage of the airspace capacity in a Free Flight environment, while maintaining safe separation between aircrafts and hazardous weather. The experiments described herein were run on a high fidelity Free Flight air traffic simulation system which allows for a variety of constraints on the computed routes and accurate measurement of environments dynamics. This permits us to estimate the desired behavior of an aircraft, including avoidance of changing hazardous weather patterns, turn and curvature constraints, and the horizontal separation standard and required time of arrival at a pre determined point, and to analyze the performance of our algorithm in various weather scenarios. The proposed Ant Colony Optimization based weather avoidance algorithm was able to find optimum weather free routes every time if they exist. In case of highly complex scenarios the algorithm comes out with the route which requires the aircraft to fly through the weather cells with least disturbances. All the solutions generated were within flight parameters and upon integration with the flight management system of the aircraft in a Free Flight air traffic simulator, successfully negotiated the bad weather.

Alam, Sameer; Abbass, Hussein A.; Barlow, Michael; Lindsay, Peter

2005-12-01

310

Urban ants of North America and Europe: identification, biology, and management by John Klotz, Laurel Hansen,  

E-print Network

Urb-ants Urban ants of North America and Europe: identification, biology, and management by John division of Cornell University Press), Ithaca and London. ISBN 978-0-8014-7473. $27.95. Ants rank among of established ant pests and also regarding the prevention of the spread of invasive ants,which pose a serious

Lucky, Andrea

311

Nectar Theft and Floral Ant-Repellence: A Link between Nectar Volume and Ant-Repellent Traits?  

PubMed Central

As flower visitors, ants rarely benefit a plant. They are poor pollinators, and can also disrupt pollination by deterring other flower visitors, or by stealing nectar. Some plant species therefore possess floral ant-repelling traits. But why do particular species have such traits when others do not? In a dry forest in Costa Rica, of 49 plant species around a third were ant-repellent at very close proximity to a common generalist ant species, usually via repellent pollen. Repellence was positively correlated with the presence of large nectar volumes. Repellent traits affected ant species differently, some influencing the behaviour of just a few species and others producing more generalised ant-repellence. Our results suggest that ant-repellent floral traits may often not be pleiotropic, but instead could have been selected for as a defence against ant thieves in plant species that invest in large volumes of nectar. This conclusion highlights to the importance of research into the cost of nectar production in future studies into ant-flower interactions. PMID:22952793

Ballantyne, Gavin; Willmer, Pat

2012-01-01

312

CURRICULUM VITAE Edward W. Muir, Jr.  

E-print Network

-93 Alice Berlin Kaplan Center for the Humanities, Fellow, 1996-97 Rockefeller Foundation, Residential University, Research Grant, Summer 1980 Gladys Krieble Delmas Foundation, Travel and Research Grant, Summer Foundation, Fellowship, 1985 The Folger Institute of the Folger Shakespeare Library Director of Seminar

Grzybowski, Bartosz A.

313

Ant colony optimisation inversion of surface and borehole magnetic data under lithological constraints  

NASA Astrophysics Data System (ADS)

The ant colony optimisation algorithm has successfully been used to invert for surface magnetic data. However, the resolution of the distributions of the recovered physical property for deeply buried magnetic sources is not generally very high because of geophysical ambiguities. We use three approaches to deal with this problem. First, the observed surface magnetic data are taken together with the three-component borehole magnetic anomalies to recover the distributions of the physical properties. This cooperative inversion strategy improves the resolution of the inversion results in the vertical direction. Additionally, as the ant colony tours the discrete nodes, we force it to visit the nodes with physical properties that agree with the drilled lithologies. These lithological constraints reduce the non-uniqueness of the inversion problem. Finally, we also implement a K-means cluster analysis for the distributions of the magnetic cells after each iteration, in order to separate the distributions of magnetisation intensity instead of concentrating the distribution in a single area. We tested our method using synthetic data and found that all tests returned favourable results. In the case study of the Mengku iron-ore deposit in northwest China, the recovered distributions of magnetisation are in good agreement with the locations and shapes of the magnetite orebodies as inferred by drillholes. Uncertainty analysis shows that the ant colony algorithm is robust in the presence of noise and that the proposed approaches significantly improve the quality of the inversion results.

Liu, Shuang; Hu, Xiangyun; Liu, Tianyou; Xi, Yufei; Cai, Jianchao; Zhang, Henglei

2015-01-01

314

Structural link prediction based on ant colony approach in social networks  

NASA Astrophysics Data System (ADS)

As the size and number of online social networks are increasing day by day, social network analysis has become a popular issue in many branches of science. The link prediction is one of the key rolling issues in the analysis of social network's evolution. As the size of social networks is increasing, the necessity for scalable link prediction algorithms is being felt more. The aim of this paper is to introduce a new unsupervised structural link prediction algorithm based on the ant colony approach. Recently, ant colony approach has been used for solving some graph problems. Different kinds of networks are used for testing the proposed approach. In some networks, the proposed scalable algorithm has the best result in comparison to other structural unsupervised link prediction algorithms. In order to evaluate the algorithm results, methods like the top- n precision, area under the Receiver Operating Characteristic (ROC) and Precision-Recall curves are carried out on real-world networks.

Sherkat, Ehsan; Rahgozar, Maseud; Asadpour, Masoud

2015-02-01

315

AntModeler analysis of mechanical stress driven transcription in three cell types  

NASA Astrophysics Data System (ADS)

Cellular stress activates transcription of various genes that mediate stress-driven proliferation and differentiation in many cells including osteoblasts, endothelial cells, and fibroblasts. In response to mechanical stress, expression of some genes is altered regardless of cell types and that of others in specific cell types. Using the microarray-based expression data for primary fibroblasts isolated from fetal mouse cornea, skin and tendon, we conducted a model-based transcription analysis and predicted transcription-factor binding motifs (TFBMs) responsible for the observed gene alteration. The computational procedure was formulated as a combinatorial optimization problem, and the AntModeler using an ant algorithm was employed to select TFBMs for each of the three fibroblast types. The results indicate that the stress responses are regulated mostly through cell type specific TFBMs together with a limited number of common TFBMs. The predicted role of those TFBMs should be evaluated experimentally.

Lin, Nan; Chen, Andy; Mackley, Jennifer R.; Winder, Steven J.; Yokota, Hiroki

2007-11-01

316

Ant queens adjust egg fertilization to benefit from both sexual and asexual reproduction.  

PubMed

An enduring problem in evolutionary biology is the near ubiquity of sexual reproduction despite the inherent cost of transmitting only half the parent's genes to progeny. Queens of some ant species circumvent this cost by using selectively both sexual reproduction and parthenogenesis: workers arise from fertilized eggs, while new queens are produced by parthenogenesis. We show that queens of the ant Cataglyphis cursor maximize the transmission rate of their genes by regulating the proportion of fertilized and parthenogenetic eggs laid over time. Parthenogenetic offspring are produced in early spring, when workers raise the brood into sexuals. After the mating period, queens lay mostly fertilized eggs that will be reared as the non-reproductive caste. PMID:21307046

Aron, S; Timmermans, I; Pearcy, M

2011-08-23

317

The Effect of Diet and Opponent Size on Aggressive Interactions Involving Caribbean Crazy Ants (Nylanderia fulva)  

PubMed Central

Biotic interactions are often important in the establishment and spread of invasive species. In particular, competition between introduced and native species can strongly influence the distribution and spread of exotic species and in some cases competition among introduced species can be important. The Caribbean crazy ant, Nylanderia fulva, was recently introduced to the Gulf Coast of Texas, and appears to be spreading inland. It has been hypothesized that competition with the red imported fire ant, Solenopsis invicta, may be an important factor in the spread of crazy ants. We investigated the potential of interspecific competition among these two introduced ants by measuring interspecific aggression between Caribbean crazy ant workers and workers of Solenopsis invicta. Specifically, we examined the effect of body size and diet on individual-level aggressive interactions among crazy ant workers and fire ants. We found that differences in diet did not alter interactions between crazy ant workers from different nests, but carbohydrate level did play an important role in antagonistic interactions with fire ants: crazy ants on low sugar diets were more aggressive and less likely to be killed in aggressive encounters with fire ants. We found that large fire ants engaged in fewer fights with crazy ants than small fire ants, but fire ant size affected neither fire ant nor crazy ant mortality. Overall, crazy ants experienced higher mortality than fire ants after aggressive encounters. Our findings suggest that fire ant workers might outcompete crazy ant workers on an individual level, providing some biotic resistance to crazy ant range expansion. However, this resistance may be overcome by crazy ants that have a restricted sugar intake, which may occur when crazy ants are excluded from resources by fire ants. PMID:23776702

Horn, Katherine C.; Eubanks, Micky D.; Siemann, Evan

2013-01-01

318

April 5, 2004 19:5 Proceedings Trim Size: 9in x 6in FuzzyAnts EFFICIENT CLUSTERING WITH FUZZY ANTS  

E-print Network

April 5, 2004 19:5 Proceedings Trim Size: 9in x 6in FuzzyAnts EFFICIENT CLUSTERING WITH FUZZY ANTS, various clustering algorithms based on the behaviour of real ants were proposed. The main advantage or the number of clusters, is needed. In this paper we show how the combination of the ant-based approach

Gent, Universiteit

319

Aphid egg protection by ants: a novel aspect of the mutualism between the tree-feeding aphid Stomaphis hirukawai and its attendant ant Lasius productus  

NASA Astrophysics Data System (ADS)

Aphids often form mutualistic associations with ants, in which the aphids provide the ants with honeydew and the ants defend the aphids from predators. In this paper, we report aphid egg protection by ants as a novel aspect of the deeply interdependent relationship between a tree-feeding aphid and its attendant ant. The ant Lasius productus harbours oviparous females, males, and eggs of the hinoki cypress-feeding aphid Stomaphis hirukawai in its nests in winter. We investigated the behaviour of ants kept with aphid eggs in petri dishes to examine whether the ants recognise the aphid eggs and tend them or only provide a refuge for the aphids. Workers carried almost all of the aphid eggs into the nest within 24 h. The ants indiscriminately tended aphid eggs collected from their own colonies and those from other ant colonies. The ants cleaned the eggs and piled them up in the nest, and egg tending by ants dramatically increased aphid egg survival rates. Starving the ants showed no significant effect on aphid egg survivorship. Without ants, aphid eggs were rapidly killed by fungi. These results suggested that grooming by the ants protected the aphid eggs, at least, against pathogenic fungi. This hygienic service afforded by the ants seems indispensable for egg survival of these aphids in an environment rich in potentially pathogenic microorganisms.

Matsuura, Kenji; Yashiro, Toshihisa

2006-10-01

320

Eggs of Mallada desjardinsi (Neuroptera: Chrysopidae) are protected by ants: the role of egg stalks in ant-tended aphid colonies.  

PubMed

In ant-aphid mutualisms, ants usually attack and exclude enemies of aphids. However, larvae of the green lacewing Mallada desjardinsi (Navas) prey on ant-tended aphids without being excluded by ants; these larvae protect themselves from ants by carrying aphid carcasses on their backs. Eggs of M. desjardinsi laid at the tips of stalks have also been observed in ant-tended aphid colonies in the field. Here, we examined whether the egg stalks of M. desjardinsi protect the eggs from ants and predators. When exposed to ants, almost all eggs with intact stalks were untouched, whereas 50-80% of eggs in which stalks had been severed at their bases were destroyed by ants. In contrast, most eggs were preyed upon by larvae of the lacewing Chrysoperla nipponensis (Okamoto), an intraguild predator of M. desjardinsi, regardless of whether their stalks had been severed. These findings suggest that egg stalks provide protection from ants but not from C. nipponensis larvae. To test whether M. desjardinsi eggs are protected from predators by aphid-tending ants, we introduced C. nipponensis larvae onto plants colonized by ant-tended aphids. A significantly greater number of eggs survived in the presence of ants because aphid-tending ants excluded larvae of C. nipponensis. This finding indicates that M. desjardinsi eggs are indirectly protected from predators by ants in ant-tended aphid colonies. PMID:25182619

Hayashi, Masayuki; Nomura, Masashi

2014-08-01

321

The Ant System: Optimization by a colony of cooperating agents  

Microsoft Academic Search

An analogy with the way ant colonies function has suggested the definition of a new computational paradigm, which we call Ant System. We propose it as a viable new approach to stochastic combinatorial optimization. The main characteristics of this model are positive feedback, distributed computation, and the use of a constructive greedy heuristic. Positive feedback accounts for rapid discovery of

Marco Dorigo; Vittorio Maniezzo; Alberto Colorni

1995-01-01

322

Ant system: optimization by a colony of cooperating agents  

Microsoft Academic Search

An analogy with the way ant colonies function has suggested the definition of a new computational paradigm, which we call ant system (AS). We propose it as a viable new approach to stochastic combinatorial optimization. The main characteristics of this model are positive feedback, distributed computation, and the use of a constructive greedy heuristic. Positive feedback accounts for rapid discovery

Marco Dorigo; Vittorio Maniezzo; Alberto Colorni

1996-01-01

323

The self-organizing exploratory pattern of the argentine ant  

Microsoft Academic Search

Workers of the Argentine ant, Iridomyrmex humilis,start to explore a chemically unmarked territory randomly. As the exploratory front advances, other explorers are recruited and a trail extends from it to the nest. Whereas recruitment trails are generally constructed between two points, these exploratory trails have no fixed destination, and strongly resemble the foraging patterns of army ants. A minimal model

J.-L. Deneubourg; S. Aron; S. Goss; J. M. Pasteels

1990-01-01

324

An Introduction to Ants (Formicidae) of the Tallgrass Prairie  

NSDL National Science Digital Library

Originally published in fall 1998 in the Missouri Prairie Journal, this newly online resource provides a brief introduction to the ecological role of ants, their taxonomy, and the effect of prairie restoration on tallgrass prairie ants (some 60 species are mentioned in table format). The publication may be downloaded as a .zip file.

325

The recovery of ant communities in regenerating temperate conifer forests  

Microsoft Academic Search

Although ants perform many critical functions in forested ecosystems, little is known about how they respond to timber harvesting, especially in temperate systems. We examined ground-foraging ant communities and 11 forest characteristics in temperate conifer forests of southwestern Oregon, USA that ranged in age from 5 to 427 years. Seven forest characteristics were related to stand age and were summarized

Jennifer D. Palladini; Maureen G. Jones; Nathan J. Sanders; Erik S. Jules

2007-01-01

326

Thelohania solenopsae as a factor of fire ant populations  

Technology Transfer Automated Retrieval System (TEKTRAN)

The inadvertent introduction of fire ants into the United States over 70 years ago initially resulted in large-scale efforts to eradicate the invasive pest. Large populations, mobility, and ability to occupy diverse habitats make fire ants a dominant arthropod in infested regions and very difficult...

327

Relative fitness of aphids: effects of plant quality and ants  

Microsoft Academic Search

We investigated the response of four species of aphids (Metopeurum fuscoviride, Brachycaudus cardui, Aphis fabae, and Macrosiphoniella tanacetaria) on tansy (Tanacetum vulgare) to plant quality and attendance by an ant, Lasius niger. The aphids experienced one of four different environments for two consecutive generations. Ant-attendance significantly affected the time needed to reach maximum fecundity only in Me. fuscoviride and plant

B. Stadler; A. F. G. Dixon; Pavel Kindlmann

2002-01-01

328

SYSTEMATICS Taxonomy and Distribution of the Argentine Ant, Linepithema humile  

E-print Network

SYSTEMATICS Taxonomy and Distribution of the Argentine Ant, Linepithema humile (Hymenoptera Ann. Entomol. Soc. Am. 97(6): 1204Ð1215 (2004) ABSTRACT The taxonomy of an invasive pest species humile, taxonomy, invasive species THE ARGENTINE ANT, Linepithema humile (Mayr) 1868, is among the world

Villemant, Claire

329

Horned lizards (Phrynosoma) incapacitate dangerous ant prey with mucus.  

PubMed

Horned lizards (Iguanidae, Phrynosomatinae, Phrynosoma) are morphologically specialized reptiles characterized by squat, tank-like bodies, short limbs, blunt snouts, spines and cranial horns, among other traits. They are unusual among lizards in the degree to which they specialize on a diet of ants, but exceptional in the number of pugnacious, highly venomous, stinging ants they consume, especially harvester ants (genus Pogonomyrmex). Like other iguanian lizards, they capture insect prey on the tongue, but unlike other lizards, they neither bite nor chew dangerous prey before swallowing. Instead, they employ a unique kinematic pattern in which prey capture, transport and swallowing are combined. Nevertheless, horned lizards consume dozens of harvester ants without harm. We show that their derived feeding kinematics are associated with unique, mucus-secreting pharyngeal papillae that apparently serve to immobilize and incapacitate dangerous ants as they are swallowed by compacting them and binding them in mucus strands. Radially branched esophageal folds provide additional mucus-secreting surfaces the ants pass through as they are swallowed. Ants extracted from fresh-killed horned lizard stomachs are curled ventrally into balls and bound in mucus. We conclude that the pharyngeal papillae, in association with a unique form of hyolingual prey transport and swallowing, are horned lizard adaptations related to a diet of dangerous prey. Harvester ant defensive weapons, along with horned lizard adaptations against such weapons, suggest a long-term, predator-prey, co-evolutionary arms race between Phrynosoma and Pogonomyrmex. PMID:18570329

Sherbrooke, Wade C; Schwenk, Kurt

2008-10-01

330

Ant Colony Optimization for vehicle routing in advanced logistics systems  

E-print Network

ways, for instance, adding more than one depot, considering more than one vehicle type, accounting, have an impact as great as the solution strategy. In this paper we present DyvOil and AntRoute, two metaheuristic such as Ant Colony System. We also describe the case of Pina Petroli, a fuel oil distribution

Gambardella, Luca Maria

331

ANT COMMUNITIES AND LIVESTOCK GRAZING IN THE GREAT BASIN, USA  

EPA Science Inventory

The objectives of this study were to determine if metrics for ant species assemblages can be used as indicators of rangeland condition, and to determine the influence of vegetation and ground cover variables, factors often influenced by livestock grazing, on ant communities. The ...

332

Science News: Ants Take a Cue From Facebook  

NSDL National Science Digital Library

A new study finds that, whereas most red harvester ants share information with a small number of nestmates, a few convey news to a wide network of others. The results help explain how ant colonies quickly respond to predators and natural disasters.

Carrie Arnold (AAAS; )

2011-04-12

333

Diversity of peptide toxins from stinging ant venoms.  

PubMed

Ants (Hymenoptera: Formicidae) represent a taxonomically diverse group of arthropods comprising nearly 13,000 extant species. Sixteen ant subfamilies have individuals that possess a stinger and use their venom for purposes such as a defence against predators, competitors and microbial pathogens, for predation, as well as for social communication. They exhibit a range of activities including antimicrobial, haemolytic, cytolytic, paralytic, insecticidal and pain-producing pharmacologies. While ant venoms are known to be rich in alkaloids and hydrocarbons, ant venoms rich in peptides are becoming more common, yet remain understudied. Recent advances in mass spectrometry techniques have begun to reveal the true complexity of ant venom peptide composition. In the few venoms explored thus far, most peptide toxins appear to occur as small polycationic linear toxins, with antibacterial properties and insecticidal activity. Unlike other venomous animals, a number of ant venoms also contain a range of homodimeric and heterodimeric peptides with one or two interchain disulfide bonds possessing pore-forming, allergenic and paralytic actions. However, ant venoms seem to have only a small number of monomeric disulfide-linked peptides. The present review details the structure and pharmacology of known ant venom peptide toxins and their potential as a source of novel bioinsecticides and therapeutic agents. PMID:25448389

Aili, Samira R; Touchard, Axel; Escoubas, Pierre; Padula, Matthew P; Orivel, Jérôme; Dejean, Alain; Nicholson, Graham M

2014-12-15

334

ACOUSTICAL ANALYSIS OF WINGBEAT FREQUENCIES FOR ALATE IMPORTED FIRE ANTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The red imported fire ant (RIFA), Solenopsis invicta Buren and the black imported fire ant (BIFA), Solenopsis richteri Forel coexist in the state of Mississippi along with reproductively viable F1 hybrids of these two species. The objective of this study was to determine and compare the wingbeat fre...

335

Zombie fire ant workers: behavior controlled by decapitating fly parasitoids  

Microsoft Academic Search

.  Laboratory observations were conducted on four separate red imported fire ant, Solenopsis invicta, colonies that contained workers parasitized by the decapitating fly, Pseudacteon tricuspis. Parasitized S. invicta workers remained inside the nest during parasitoid larval development and left the nest approximately 8 – 10 hours before\\u000a decapitation by the parasitoid. When parasitized ants left the nest, they were highly mobile,

D. C. Henne; S. J. Johnson

2007-01-01

336

Fire ant polymorphism: the ergonomics of brood production  

Microsoft Academic Search

Social organization is generally assumed to increase colony efficiency and survival; however, little quantitative information is available to support this assumption. Polymorphism is an important aspect of labor division in colonies of the fire ant, Solenopsis invicta. Our objective was to investigate the effect of fire ant polymorphism on brood production efficiency. We set up standardized polymorphic colonies with a

Sanford D. Porter; Walter R. Tschinkel

1985-01-01

337

The birth of ant genomics Raghavendra Gadagkar1  

E-print Network

The birth of ant genomics Raghavendra Gadagkar1 Centre for Ecological Sciences and Centre division of labor and most impressive levels of communication and coordination among colony members (Fig 1 journal (6), taking the total to six. Thus, we are truly witnessing the birth of ant ge- nomics, indeed

Gadagkar, Raghavendra

338

URBAN DYNAMICS MODELLING USING ANT NEST BUILDING Rawan Ghnemat(1)  

E-print Network

URBAN DYNAMICS MODELLING USING ANT NEST BUILDING Rawan Ghnemat(1) , Cyrille Bertelle(1) , G´erard H, to model and analyze cultural equipment dynamics in urban area. INTRODUCTION Many natural and artificial intelligence, complex systems, self-organization, ant systems, spatial organization ABSTRACT Urban dynamics

Paris-Sud XI, Université de

339

Transgenerational effects and the cost of ant tending in aphids.  

PubMed

In mutualistic interactions, partners obtain a net benefit, but there may also be costs associated with the provision of benefits for a partner. The question of whether aphids suffer such costs when attended by ants has been raised in previous work. Transgenerational effects, where offspring phenotypes are adjusted based on maternal influences, could be important in the mutualistic interaction between aphids and ants, in particular because aphids have telescoping generations where two offspring generations can be present in a mature aphid. We investigated the immediate and transgenerational influence of ant tending on aphid life history and reproduction by observing the interaction between the facultative myrmecophile Aphis fabae and the ant Lasius niger over 13 aphid generations in the laboratory. We found that the effect of ant tending changes dynamically over successive aphid generations after the start of tending. Initially, total aphid colony weight, aphid adult weight and aphid embryo size decreased compared with untended aphids, consistent with a cost of ant association, but these differences disappeared within four generations of interaction. We conclude that transgenerational effects are important in the aphid-ant interactions and that the costs for aphids of being tended by ants can vary over generations. PMID:23689730

Tegelaar, Karolina; Glinwood, Robert; Pettersson, Jan; Leimar, Olof

2013-11-01

340

Ant-Based Load Balancing in Telecommunications Networks  

Microsoft Academic Search

This paper describes a novel method of achieving load balancing in telecommunicationsnetworks. A simulated network models a typical distribution of calls betweennodes; nodes carrying an excess of traffic can become congested, causing calls to belost. In addition to calls, the network also supports a population of simple mobile agentswith behaviours modelled on the trail laying abilities of ants. The ants

Ruud Schoonderwoerd; Owen Holland Janet Bruten; Leon Rothkrantz

1996-01-01

341

Butterfly Project Report Ant Farm: A Lightweight Process Programming  

E-print Network

Butterfly Project Report 21 Ant Farm: A Lightweight Process Programming Environment M.L. Scott is a library package for the BBN Butterfly Parallel Processor that allows programs to split computational effort across many lightweight threads of control. On each node of the Butterfly, Ant Farm provides

Scott, Michael L.

342

Linking Science and Writing With Two Bad Ants  

NSDL National Science Digital Library

Two Bad Ants , a fictional story detailing the journey of "two bad ants" that stray from their colony and choose to stay in a container full of large, white, sweet-tasking crystals (sugar)--was the catalyst for an engaging five-day study with third

Fournier, Ingrid H.; Edison, Leslie D.

2009-07-01

343

Odorous House Ants (Tapinoma sessile) as Back-Seat Drivers of Localized Ant Decline in Urban Habitats.  

PubMed

Invasive species and habitat disturbance threaten biodiversity worldwide by modifying ecosystem performance and displacing native organisms. Similar homogenization impacts manifest locally when urbanization forces native species to relocate or reinvade perpetually altered habitat. This study investigated correlations between ant richness and abundance in response to urbanization and the nearby presence of invasive ant species, odorous house ants (Tapinoma sessile), within its native region. Surveying localized ant composition within natural, semi-natural, and urban habitat supported efforts to determine whether T. sessile appear to be primary (drivers) threats as instigators or secondary (passengers) threats as inheritors of indigenous ant decline. Sampling 180 sites, evenly split between all habitats with and without T. sessile present, yielded 45 total species. Although urbanization and T. sessile presence factors were significantly linked to ant decline, their interaction correlated to the greatest reduction of total ant richness (74%) and abundance (81%). Total richness appeared to decrease from 27 species to 18 when natural habitat is urbanized and from 18 species to 7 with T. sessile present in urban plots. Odorous house ant presence minimally influenced ant communities within natural and semi-natural habitat, highlighting the importance of habitat alteration and T. sessile presence interactions. Results suggest urbanization releases T. sessile from unknown constraints by decreasing ant richness and competition. Within urban environment, T. sessile are pre-adapted to quickly exploit new resources and grow to supercolony strength wherein T. sessile drive adjacent biodiversity loss. Odorous house ants act as passengers and drivers of ecological change throughout different phases of urban 'invasion'. This progression through surviving habitat alteration, exploiting new resources, thriving, and further reducing interspecific competition supports a "back-seat driver" role and affects pest management strategies. As demonstrated by T. sessile, this article concludes native species can become back-seat drivers of biodiversity loss and potentially thrive as "metro-invasive" species. PMID:25551819

Salyer, Adam; Bennett, Gary W; Buczkowski, Grzegorz A

2014-01-01

344

Odorous House Ants (Tapinoma sessile) as Back-Seat Drivers of Localized Ant Decline in Urban Habitats  

PubMed Central

Invasive species and habitat disturbance threaten biodiversity worldwide by modifying ecosystem performance and displacing native organisms. Similar homogenization impacts manifest locally when urbanization forces native species to relocate or reinvade perpetually altered habitat. This study investigated correlations between ant richness and abundance in response to urbanization and the nearby presence of invasive ant species, odorous house ants (Tapinoma sessile), within its native region. Surveying localized ant composition within natural, semi-natural, and urban habitat supported efforts to determine whether T. sessile appear to be primary (drivers) threats as instigators or secondary (passengers) threats as inheritors of indigenous ant decline. Sampling 180 sites, evenly split between all habitats with and without T. sessile present, yielded 45 total species. Although urbanization and T. sessile presence factors were significantly linked to ant decline, their interaction correlated to the greatest reduction of total ant richness (74%) and abundance (81%). Total richness appeared to decrease from 27 species to 18 when natural habitat is urbanized and from 18 species to 7 with T. sessile present in urban plots. Odorous house ant presence minimally influenced ant communities within natural and semi-natural habitat, highlighting the importance of habitat alteration and T. sessile presence interactions. Results suggest urbanization releases T. sessile from unknown constraints by decreasing ant richness and competition. Within urban environment, T. sessile are pre-adapted to quickly exploit new resources and grow to supercolony strength wherein T. sessile drive adjacent biodiversity loss. Odorous house ants act as passengers and drivers of ecological change throughout different phases of urban ‘invasion’. This progression through surviving habitat alteration, exploiting new resources, thriving, and further reducing interspecific competition supports a “back-seat driver” role and affects pest management strategies. As demonstrated by T. sessile, this article concludes native species can become back-seat drivers of biodiversity loss and potentially thrive as “metro-invasive” species. PMID:25551819

Salyer, Adam; Bennett, Gary W.; Buczkowski, Grzegorz A.

2014-01-01

345

Systemutic Entomology (1992) 17, 301-329 The internal phylogeny of ants (Hymenoptera  

E-print Network

Systemutic Entomology (1992) 17, 301-329 The internal phylogeny of ants (Hymenoptera: Formicidae: the 14 currently recognized ant subfamilies plus 5 po- tentially critical infrasubfamilialtaxa. Clades appearing within these groups included the Cerapachyinae plus `army ants', the Nothomyrmeciinae

Villemant, Claire

346

9 CFR 354.123 - Segregation of suspects on ante-mortem inspection.  

Code of Federal Regulations, 2010 CFR

...Segregation of suspects on ante-mortem inspection. 354.123 Section 354.123 Animals and Animal Products FOOD SAFETY AND INSPECTION...Inspection Procedures; Ante-Mortem Inspections § 354.123 Segregation of suspects on ante-mortem...

2010-01-01

347

Ultraviolet radiation as an ant repellent  

SciTech Connect

In an effort to repel red imported fire ants (RIFA) from electrical devices, such as transformers, ultraviolet (UV) light was tested. Initial tests determined if RIFA`s tolerate a UV-irradiated environment when given a choice between UV-irradiated and non-irradiated. All replications in this test indicated that RIFA`s are intolerant of UV-irradiation and sought to escape it. RIFA`s moved to shaded environments and transported their brood out its well. A second test sought to determine if long-term UV-irradiation of the entire colonies cause increased RIFA mortality. Queenright colonies were exposed to UV irradiation of 254nm constantly for 115 days and colonies had a higher mortality rate than did a control colony. RIFA`s attempted to escape UV light and had increased rate when exposed to UV (254nm), but a practical application of this technique may be detrimental to insulation on electrical wiring.

Thorvilson, H.G.; Russell, S.A.; Green, B.; Gransberg, D. [Texas Tech Univ., Lubbock, TX (United States)

1996-12-31

348

Assessing ant seed predation in threatened plants: a case study  

NASA Astrophysics Data System (ADS)

Erodium paularense is a threatened plant species that is subject to seed predation by the granivorous ant Messor capitatus. In this paper we assessed the intensity and pattern of ant seed predation and looked for possible adaptive strategies at the seed and plant levels to cope with this predation. Seed predation was estimated in 1997 and 1998 at the population level by comparing total seed production and ant consumption, assessed by counting seed hulls in refuse piles. According to this method, ant seed predation ranged between 18% and 28%. A more detailed and direct assessment conducted in 1997 raised this estimate to 43%. In this assessment spatial and temporal patterns of seed predation by ants were studied by mapping all nest entrances in the studied area and marking the mature fruits of 109 reproductive plants with a specific colour code throughout the seed dispersal period. Intact fruit coats were later recovered from the refuse piles, and their mother plants and time of dispersal were identified. Seeds dispersed at the end of the dispersal period had a greater probability of escaping from ant seed predation. Similarly, in plants with late dispersal a greater percentage of seeds escaped from ant predation. Optimum dispersal time coincided with the maximum activity of granivorous ants because, at this time, ants focused their harvest on other plant species of the community. It was also observed that within-individual seed dispersal asynchrony minimised seed predation. From a conservation perspective, results show that the granivorous ant-plant interaction cannot be assessed in isolation and that the intensity of its effects basically depends on the seed dispersal pattern of the other members of the plant community. Furthermore, this threat must be assessed by considering the overall situation of the target population. Thus, in E. paularense, the strong limitation of safe-sites for seedling establishment reduces the importance of seed predation.

Albert, María José; Escudero, Adrián; Iriondo, José María

2005-11-01

349

The Regulation of Ant Colony Foraging Activity without Spatial Information  

PubMed Central

Many dynamical networks, such as the ones that produce the collective behavior of social insects, operate without any central control, instead arising from local interactions among individuals. A well-studied example is the formation of recruitment trails in ant colonies, but many ant species do not use pheromone trails. We present a model of the regulation of foraging by harvester ant (Pogonomyrmex barbatus) colonies. This species forages for scattered seeds that one ant can retrieve on its own, so there is no need for spatial information such as pheromone trails that lead ants to specific locations. Previous work shows that colony foraging activity, the rate at which ants go out to search individually for seeds, is regulated in response to current food availability throughout the colony's foraging area. Ants use the rate of brief antennal contacts inside the nest between foragers returning with food and outgoing foragers available to leave the nest on the next foraging trip. Here we present a feedback-based algorithm that captures the main features of data from field experiments in which the rate of returning foragers was manipulated. The algorithm draws on our finding that the distribution of intervals between successive ants returning to the nest is a Poisson process. We fitted the parameter that estimates the effect of each returning forager on the rate at which outgoing foragers leave the nest. We found that correlations between observed rates of returning foragers and simulated rates of outgoing foragers, using our model, were similar to those in the data. Our simple stochastic model shows how the regulation of ant colony foraging can operate without spatial information, describing a process at the level of individual ants that predicts the overall foraging activity of the colony. PMID:22927811

Prabhakar, Balaji; Dektar, Katherine N.; Gordon, Deborah M.

2012-01-01

350

Research on remote sensing image segmentation based on ant colony algorithm: take the land cover classification of middle Qinling Mountains for example  

NASA Astrophysics Data System (ADS)

Remote sensing image based on the complexity of the background features, has a wealth of spatial information, how to extract huge amounts of data in the region of interest is a serious problem. Image segmentation refers to certain provisions in accordance with the characteristics of the image into different regions, and it is the key of remote sensing image recognition and information extraction. Reasonably fast image segmentation algorithm is the base of image processing; traditional segmentation methods have a lot of the limitations. Traditional threshold segmentation method in essence is an ergodic process, the low efficiency impacts on its application. The ant colony algorithm is a populationbased evolutionary algorithm heuristic biomimetic, since proposed, it has been successfully applied to the TSP, job-shop scheduling problem, network routing problem, vehicle routing problem, as well as other cluster analysis. Ant colony optimization algorithm is a fast heuristic optimization algorithm, easily integrates with other methods, and it is robust. Improved ant colony algorithm can greatly enhance the speed of image segmentation, while reducing the noise on the image. The research background of this paper is land cover classification experiments according to the SPOT images of Qinling area. The image segmentation based on ant colony algorithm is carried out and compared with traditional methods. Experimental results show that improved the ant colony algorithm can quickly and accurately segment target, and it is an effective method of image segmentation, it also has laid a good foundation of image classification for the follow-up work.

Mei, Xin; Wang, Qian; Wang, Quanfang; Lin, Wenfang

2009-10-01

351

Desert ants achieve reliable recruitment across noisy interactions  

PubMed Central

We study how desert ants, Cataglyphis niger, a species that lacks pheromone-based recruitment mechanisms, inform each other about the presence of food. Our results are based on automated tracking that allows us to collect a large database of ant trajectories and interactions. We find that interactions affect an ant's speed within the nest. Fast ants tend to slow down, whereas slow ones increase their speed when encountering a faster ant. Faster ants tend to exit the nest more frequently than slower ones. So, if an ant gains enough speed through encounters with others, then she tends to leave the nest and look for food. On the other hand, we find that the probability for her to leave the nest depends only on her speed, but not on whether she had recently interacted with a recruiter that has found the food. This suggests a recruitment system in which ants communicate their state by very simple interactions. Based on this assumption, we estimate the information-theoretical channel capacity of the ants’ pairwise interactions. We find that the response to the speed of an interacting nest-mate is very noisy. The question is then how random interactions with ants within the nest can be distinguished from those interactions with a recruiter who has found food. Our measurements and model suggest that this distinction does not depend on reliable communication but on behavioural differences between ants that have found the food and those that have not. Recruiters retain high speeds throughout the experiment, regardless of the ants they interact with; non-recruiters communicate with a limited number of nest-mates and adjust their speed following these interactions. These simple rules lead to the formation of a bistable switch on the level of the group that allows the distinction between recruitment and random noise in the nest. A consequence of the mechanism we propose is a negative effect of ant density on exit rates and recruitment success. This is, indeed, confirmed by our measurements. PMID:23486172

Razin, Nitzan; Eckmann, Jean-Pierre; Feinerman, Ofer

2013-01-01

352

Overview of the Distribution, Habitat Association and Impact of Exotic Ants on Native Ant Communities in New Caledonia  

PubMed Central

Ants are among the most ubiquitous and harmful invaders worldwide, but there are few regional studies of their relationships with habitat and native ant communities. New Caledonia has a unique and diverse ant fauna that is threatened by exotic ants, but broad-scale patterns of exotic and native ant community composition in relation to habitat remain poorly documented. We conducted a systematic baiting survey of 56 sites representing the main New Caledonian habitat types: rainforest on ultramafic soils (15 sites), rainforest on volcano-sedimentary soils (13), maquis shrubland (15), Melaleuca-dominated savannas (11) and Acacia spirorbis thickets (2). We collected a total of 49 species, 13 of which were exotic. Only five sites were free of exotic species, and these were all rainforest. The five most abundant exotic species differed in their habitat association, with Pheidole megacephala associated with rainforests, Brachymyrmex cf. obscurior with savanna, and Wasmannia auropunctata and Nylanderia vaga present in most habitats. Anoplolepis gracilipes occurred primarily in maquis-shrubland, which contrasts with its rainforest affinity elsewhere. Multivariate analysis of overall ant species composition showed strong differentiation of sites according to the distribution of exotic species, and these patterns were maintained at the genus and functional group levels. Native ant composition differed at invaded versus uninvaded rainforest sites, in the absence of differences in habitat variables. Generalised Myrmicinae and Forest Opportunists were particularly affected by invasion. There was a strong negative relationship between the abundance of W. auropunctata and native ant abundance and richness. This emphasizes that, in addition to dominating many ant communities numerically, some exotic species, and in particular W. auropunctata, have a marked impact on native ant communities. PMID:23840639

Berman, Maïa; Andersen, Alan N.; Hély, Christelle; Gaucherel, Cédric

2013-01-01

353

Species richness, equitability, and abundance of ants in disturbed landscapes  

USGS Publications Warehouse

Ants are used as indicators of environmental change in disturbed landscapes, often without adequate understanding of their response to disturbance. Ant communities in the southeastern United States displayed a hump-backed species richness curve against an index of landscape disturbance. Forty sites at Fort Benning, in west-central Georgia, covered a spectrum of habitat disturbance (military training and fire) in upland forest. Sites disturbed by military training had fewer trees, less canopy cover, more bare ground, and warmer, more compact soils with shallower A-horizons. We sampled ground-dwelling ants with pitfall traps, and measured 15 habitat variables related to vegetation and soil. Ant species richness was greatest with a relative disturbance of 43%, but equitability was greatest with no disturbance. Ant abundance was greatest with a relative disturbance of 85%. High species richness at intermediate disturbance was associated with greater within-site spatial heterogeneity. Species richness was also associated with intermediate values of the normalized difference vegetation index (NDVI), a correlate of net primary productivity (NPP). Available NPP (the product of NDVI and the fraction of days that soil temperature exceeded 25 ??C), however, was positively correlated with species richness, though not with ant abundance. Species richness was unrelated to soil texture, total ground cover, and fire frequency. Ant species richness and equitability are potential state indicators of the soil arthropod community. Moreover, equitability can be used to monitor ecosystem change. ?? 2008 Elsevier Ltd.

Graham, J.H.; Krzysik, A.J.; Kovacic, D.A.; Duda, J.J.; Freeman, D.C.; Emlen, J.M.; Zak, J.C.; Long, W.R.; Wallace, M.P.; Chamberlin-Graham, C.; Nutter, J.P.; Balbach, H.E.

2009-01-01

354

Newly discovered sister lineage sheds light on early ant evolution  

PubMed Central

Ants are the world's most conspicuous and important eusocial insects and their diversity, abundance, and extreme behavioral specializations make them a model system for several disciplines within the biological sciences. Here, we report the discovery of a new ant that appears to represent the sister lineage to all extant ants (Hymenoptera: Formicidae). The phylogenetic position of this cryptic predator from the soils of the Amazon rainforest was inferred from several nuclear genes, sequenced from a single leg. Martialis heureka (gen. et sp. nov.) also constitutes the sole representative of a new, morphologically distinct subfamily of ants, the Martialinae (subfam. nov.). Our analyses have reduced the likelihood of long-branch attraction artifacts that have troubled previous phylogenetic studies of early-diverging ants and therefore solidify the emerging view that the most basal extant ant lineages are cryptic, hypogaeic foragers. On the basis of morphological and phylogenetic evidence we suggest that these specialized subterranean predators are the sole surviving representatives of a highly divergent lineage that arose near the dawn of ant diversification and have persisted in ecologically stable environments like tropical soils over great spans of time. PMID:18794530

Rabeling, Christian; Brown, Jeremy M.; Verhaagh, Manfred

2008-01-01

355

Wasps robbing food from ants: a frequent behavior?  

NASA Astrophysics Data System (ADS)

Food robbing, or cleptobiosis, has been well documented throughout the animal kingdom. For insects, intrafamilial food robbing is known among ants, but social wasps (Vespidae; Polistinae) taking food from ants has, to the best of our knowledge, never been reported. In this paper, we present two cases involving social wasps robbing food from ants associated with myrmecophytes. (1) Polybioides tabida F. (Ropalidiini) rob pieces of prey from Tetraponera aethiops Smith (Formicidae; Pseudomyrmecinae) specifically associated with Barteria fistulosa Mast. (Passifloraceae). (2) Charterginus spp. (Epiponini) rob food bodies from myrmecophytic Cecropia (Cecropiaceae) exploited by their Azteca mutualists (Formicidae; Dolichoderinae) or by opportunistic ants (that also attack cleptobiotic wasps). We note here that wasps gather food bodies (1) when ants are not yet active; (2) when ants are active, but avoiding any contact with them by flying off when attacked; and (3) through the coordinated efforts of two to five wasps, wherein one of them prevents the ants from leaving their nest, while the other wasps freely gather the food bodies. We suggest that these interactions are more common than previously thought.

Lapierre, Louis; Hespenheide, Henry; Dejean, Alain

2007-12-01

356

Stridulations Reveal Cryptic Speciation in Neotropical Sympatric Ants  

PubMed Central

The taxonomic challenge posed by cryptic species underlines the importance of using multiple criteria in species delimitation. In the current paper we tested the use of acoustic analysis as a tool to assess the real diversity in a cryptic species complex of Neotropical ants. In order to understand the potential of acoustics and to improve consistency in the conclusions by comparing different approaches, phylogenetic relationships of all the morphs considered were assessed by the analysis of a fragment of the mitochondrial DNA cytochrome b. We observed that each of the cryptic morph studied presents a morphologically distinct stridulatory organ and that all sympatric morphs produce distinctive stridulations. This is the first evidence of such a degree of specialization in the acoustic organ and signals in ants, which suggests that stridulations may be among the cues used by these ants during inter-specific interactions. Mitochondrial DNA variation corroborated the acoustic differences observed, confirming acoustics as a helpful tool to determine cryptic species in this group of ants, and possibly in stridulating ants in general. Congruent morphological, acoustic and genetic results constitute sufficient evidence to propose each morph studied here as a valid new species, suggesting that P. apicalis is a complex of at least 6 to 9 species, even if they present different levels of divergence. Finally, our results highlight that ant stridulations may be much more informative than hitherto thought, as much for ant communication as for integrative taxonomists. PMID:21203529

Ferreira, Ronara Souza; Poteaux, Chantal; Delabie, Jacques Hubert Charles; Fresneau, Dominique; Rybak, Fanny

2010-01-01

357

Ant-mediated seed dispersal in a warmed world.  

PubMed

Climate change affects communities both directly and indirectly via changes in interspecific interactions. One such interaction that may be altered under climate change is the ant-plant seed dispersal mutualism common in deciduous forests of eastern North America. As climatic warming alters the abundance and activity levels of ants, the potential exists for shifts in rates of ant-mediated seed dispersal. We used an experimental temperature manipulation at two sites in the eastern US (Harvard Forest in Massachusetts and Duke Forest in North Carolina) to examine the potential impacts of climatic warming on overall rates of seed dispersal (using Asarum canadense seeds) as well as species-specific rates of seed dispersal at the Duke Forest site. We also examined the relationship between ant critical thermal maxima (CTmax) and the mean seed removal temperature for each ant species. We found that seed removal rates did not change as a result of experimental warming at either study site, nor were there any changes in species-specific rates of seed dispersal. There was, however, a positive relationship between CTmax and mean seed removal temperature, whereby species with higher CTmax removed more seeds at hotter temperatures. The temperature at which seeds were removed was influenced by experimental warming as well as diurnal and day-to-day fluctuations in temperature. Taken together, our results suggest that while temperature may play a role in regulating seed removal by ants, ant plant seed-dispersal mutualisms may be more robust to climate change than currently assumed. PMID:24688863

Stuble, Katharine L; Patterson, Courtney M; Rodriguez-Cabal, Mariano A; Ribbons, Relena R; Dunn, Robert R; Sanders, Nathan J

2014-01-01

358

Weaver ant role in cashew orchards in Vietnam.  

PubMed

Cashew (Anacardium occidentale L.) is a very important source of income for more than 200,000 farmer households in Vietnam. The present cashew productivity in Vietnam is low and unstable, and pest damage is partly responsible for this. Cashew farmers rely on pesticides to minimize the damage, resulting in adverse impacts on farm environment and farmers' health. Weaver ants (Oecophylla spp) are effective biocontrol agents of a range of cashew insect pests in several cashew-growing countries, and these ants are widely distributed in Vietnam. The aim of this study is to evaluate the potential of weaver ants in cashew orchards in Vietnam. Field surveys and field experiment were conducted in five cashew orchards from July 2006 to January 2008 in Binh Phuoc, Dong Nai, and Ba Ria Vung Tau provinces, Vietnam. Based on the field surveys, the most important pests that damage flushing foliar and floral shoots and young cashew fruits and nuts were mosquito bugs, brown shoot borers, blue shoot borers, and fruit-nut borers. The damage caused by each of these pests was significantly lower on trees with weaver ants compared with trees without the ants, showing that the ants were able to keep these pest damages under the control threshold. Regular monitoring of the field experiment showed that weaver ants were similar to insecticides for controlling mosquito bugs, blue shoot borers, fruit-nut borers, leaf rollers, and leaf miners. Aphids did not become major pests in plot with weaver ants. To manage insect pest assemblage in cashew orchards, an integrated pest management using weaver ants as a major component is discussed. PMID:25195419

Peng, Renkang; Lan, La Pham; Christian, Keith

2014-08-01

359

Prey capture kinematics of ant-eating lizards.  

PubMed

While morphological and behavioral feeding specializations are obvious in many vertebrate groups, among lizards there appear to be few dietary specialists. By comparing the prey capture kinematics and overall feeding behavior in two highly specialized ant-eating lizards (Moloch horridus and Phrynosoma platyrhinos) with those of two closely related dietary generalists (Pogona vitticeps and Uma notata), we investigate whether dietary specialization has been accompanied by changes in the function and use of the feeding system. We quantified kinematic variables from high-speed video recordings (200-250 frames s(-1)) of each species feeding on ants. Prey capture was strikingly different in M. horridus to that of other species, being characterized by a suite of unusual behaviors including the lack of a body lunge, faster tongue protrusion, reduced prey processing and, most notably, the ability to modulate the slow open phase of the gape cycle. In concert, these traits make a single feeding event in M. horridus faster than that in any other iguanian lizard studied to date. Prey capture behavior in P. platyrhinos is kinematically more similar to U. notata and P. vitticeps than to M. horridus, but the ant specialists are similar in that both lack distinct prey processing behaviors, resulting in faster overall capture and feeding events. While ant feeding in P. vitticeps is faster than feeding on other prey, the duration of a single feeding event is still four times longer than in either ant specialist, because of extensive prey processing. Additionally, a phylogenetic comparison of ant specialist lizards with dietary generalists revealed that ant-eating lizards require significantly less time to capture and process prey. Thus there are not only significant behavioral modifications in these ant-eating lizards, but also multiple strategies among specialists, suggesting differing selective pressures or phylogenetic constraints in the evolution of ant eating in lizards. PMID:15601883

Meyers, Jay J; Herrel, Anthony

2005-01-01

360

Vision-independent odometry in the ant Cataglyphis cursor  

NASA Astrophysics Data System (ADS)

In contrast to flying insects, in which distance estimation is visually mediated, self-induced image motion and use of familiar landmarks are known to play a minor role in ants. Here we show that strictly diurnal Cataglyphis cursor ants can gauge with accuracy the distance they have travelled even in complete darkness in the absence of any other cues, i.e. chemical or protocounting information. Thus, an ant's odometer is a vision-independent system based on proprioceptive cues, implicating some form of step counting, which remain to be elucidated.

Thiélin-Bescond, Mary; Beugnon, Guy

2005-04-01

361

Vision-independent odometry in the ant Cataglyphis cursor.  

PubMed

In contrast to flying insects, in which distance estimation is visually mediated, self-induced image motion and use of familiar landmarks are known to play a minor role in ants. Here we show that strictly diurnal Cataglyphis cursor ants can gauge with accuracy the distance they have travelled even in complete darkness in the absence of any other cues, i.e. chemical or protocounting information. Thus, an ant's odometer is a vision-independent system based on proprioceptive cues, implicating some form of step counting, which remain to be elucidated. PMID:15772808

Thiélin-Bescond, Mary; Beugnon, Guy

2005-04-01

362

Ant search strategies after interrupted tandem runs.  

PubMed

Tandem runs are a form of recruitment in ants. During a tandem run, a single leader teaches one follower the route to important resources such as sources of food or better nest sites. In the present study, we investigate what tandem leaders and followers do, in the context of nest emigration, if their partner goes missing. Our experiments involved removing either leaders or followers at set points during tandem runs. Former leaders first stand still and wait for their missing follower but then most often proceed alone to the new nest site. By contrast, former followers often first engage in a Brownian search, for almost exactly the time that their former leader should have waited for them, and then former followers switch to a superdiffusive search. In this way, former followers first search their immediate neighbourhood for their lost leader before becoming ever more wide ranging so that in the absence of their former leader they can often find the new nest, re-encounter the old one or meet a new leader. We also show that followers gain useful information even from incomplete tandem runs. These observations point to the important principle that sophisticated communication behaviours may have evolved as anytime algorithms, i.e. procedures that are beneficial even if they do not run to completion. PMID:20435821

Franks, Nigel R; Richardson, Thomas O; Keir, Samantha; Inge, Stephen J; Bartumeus, Frederic; Sendova-Franks, Ana B

2010-05-01

363

Recognition in Ants: Social Origin Matters  

PubMed Central

The ability of group members to discriminate against foreigners is a keystone in the evolution of sociality. In social insects, colony social structure (number of queens) is generally thought to influence abilities of resident workers to discriminate between nestmates and non-nestmates. However, whether social origin of introduced individuals has an effect on their acceptance in conspecific colonies remains poorly explored. Using egg-acceptance bioassays, we tested the influence of social origin of queen-laid eggs on their acceptance by foreign workers in the ant Formica selysi. We showed that workers from both single- and multiple-queen colonies discriminated against foreign eggs from single-queen colonies, whereas they surprisingly accepted foreign eggs from multiple-queen colonies. Chemical analyses then demonstrated that social origins of eggs and workers could be discriminated on the basis of their chemical profiles, a signal generally involved in nestmate discrimination. These findings provide the first evidence in social insects that social origins of eggs interfere with nestmate discrimination and are encoded by chemical signatures. PMID:21573235

Meunier, Joël; Delémont, Olivier; Lucas, Christophe

2011-01-01

364

Public goods dilemma in asexual ant societies.  

PubMed

Cooperation in biological, social, and economic groups is underpinned by public goods that are generated by group members at some personal cost. Theory predicts that public goods will be exploited by cheaters who benefit from the goods by not paying for them, thereby leading to the collapse of cooperation. This situation, described as the "public goods dilemma" in game theory, makes the ubiquity of cooperation a major evolutionary puzzle. Despite this generalization, the demonstration of genetic background and fitness effects of the public goods dilemma has been limited to interactions between viruses and between cells, and thus its relevance at higher levels of organismal complexity is still largely unexplored. Here we provide experimental evidence for the public goods dilemma in a social insect, the ant Pristomyrmex punctatus. In this species, all workers are involved in both asexual reproduction and cooperative tasks. Genetic cheaters infiltrate field colonies, reproducing more than the workers but shunning cooperative tasks. In laboratory experiments, cheaters outcompeted coexisting workers in both survival and reproduction, although a group composed only of cheaters failed to produce offspring. The operations of the public goods dilemma in P. punctatus showed a remarkable convergence with those in microbial societies, not only in fitness consequences but also in behavioral mechanisms. Our study reinforces the evolutionary impact of cheaters on diverse cooperative systems in the laboratory and in the field. PMID:24046364

Dobata, Shigeto; Tsuji, Kazuki

2013-10-01

365

Public goods dilemma in asexual ant societies  

PubMed Central

Cooperation in biological, social, and economic groups is underpinned by public goods that are generated by group members at some personal cost. Theory predicts that public goods will be exploited by cheaters who benefit from the goods by not paying for them, thereby leading to the collapse of cooperation. This situation, described as the “public goods dilemma” in game theory, makes the ubiquity of cooperation a major evolutionary puzzle. Despite this generalization, the demonstration of genetic background and fitness effects of the public goods dilemma has been limited to interactions between viruses and between cells, and thus its relevance at higher levels of organismal complexity is still largely unexplored. Here we provide experimental evidence for the public goods dilemma in a social insect, the ant Pristomyrmex punctatus. In this species, all workers are involved in both asexual reproduction and cooperative tasks. Genetic cheaters infiltrate field colonies, reproducing more than the workers but shunning cooperative tasks. In laboratory experiments, cheaters outcompeted coexisting workers in both survival and reproduction, although a group composed only of cheaters failed to produce offspring. The operations of the public goods dilemma in P. punctatus showed a remarkable convergence with those in microbial societies, not only in fitness consequences but also in behavioral mechanisms. Our study reinforces the evolutionary impact of cheaters on diverse cooperative systems in the laboratory and in the field. PMID:24046364

Dobata, Shigeto; Tsuji, Kazuki

2013-01-01

366

A Possibility of the Aeromagnetic Survey by a Small Unmanned Aerial Vehicles, Ant-Plane  

NASA Astrophysics Data System (ADS)

Magnetic surveys by helicopters and airplanes are a useful technique to estimate the geological structure under the ice sheets in Antarctica. However, it is not easy to employ this due to the transportation of the planes, logistic supports, security, and financial problems. Members of Ant-Plane Project have investigated the unmanned aerial vehicles (UAV, Ant-Plane) for the solution of the problems. Recently the aeromagnetic survey is verified by a model airplane navigated by GPS and a magneto-resistant (MR) magnetometer. The airplane (Ant-Plane) consists of 2m wing length, 2-cycles and 2-cylinder 85cc gasoline engine, GPS navigation system by microcomputer and radio telemeter system. The total weight is 15kg including 2 litter fuels, the MR magnetometer, a video camera and an emergency parachute. The speed is 130 km/h and maximum height is 2000m. The magnetometer system consists of a 3- component MR magnetometer, GPS and data logger. Three components of magnetic field, latitude, longitude, altitude, number of satellite and time are recorded in every second during 3 hours. The sensitivity of the magnetometer is 7 nT and we use a total magnetic field intensity for magnetic analysis due to unknown heading of the plane. November 2003 we succeeded the magnetic survey by the Ant-Plane at the slope of Sakurajima Volcano, Kyushu, Japan. The plane rotated 9 times along the programmed route of about 4x1 km, total flight distance of 80 km, keeping the altitude of 700 m. Consequently we obtained almost similar field variation on the route. The maximum deviation of each course was less than 100 m. Therefore, we concluded that the aeromagnetic survey in the relatively large anomaly areas can be performed by Ant-Plane with the MR magnetometer system. Finally the plane flew up 1400m with a video camera to take the photo of active volcano Sakurajima (1117m). It succeeded to take photos of craters through steam from the volcano.

Funaki, M.

2004-12-01

367

An ant colony optimization algorithm for phylogenetic estimation under the minimum evolution principle  

PubMed Central

Background Distance matrix methods constitute a major family of phylogenetic estimation methods, and the minimum evolution (ME) principle (aiming at recovering the phylogeny with shortest length) is one of the most commonly used optimality criteria for estimating phylogenetic trees. The major difficulty for its application is that the number of possible phylogenies grows exponentially with the number of taxa analyzed and the minimum evolution principle is known to belong to the NP MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacPC6xNi=xH8viVGI8Gi=hEeeu0xXdbba9frFj0xb9qqpG0dXdb9aspeI8k8fiI+fsY=rqGqVepae9pg0db9vqaiVgFr0xfr=xfr=xc9adbaqaaeGacaGaaiaabeqaaeqabiWaaaGcbaWenfgDOvwBHrxAJfwnHbqeg0uy0HwzTfgDPnwy1aaceaGae8xdX7Kaeeiuaafaaa@3888@-hard class of problems. Results In this paper, we introduce an Ant Colony Optimization (ACO) algorithm to estimate phylogenies under the minimum evolution principle. ACO is an optimization technique inspired from the foraging behavior of real ant colonies. This behavior is exploited in artificial ant colonies for the search of approximate solutions to discrete optimization problems. Conclusion We show that the ACO algorithm is potentially competitive in comparison with state-of-the-art algorithms for the minimum evolution principle. This is the first application of an ACO algorithm to the phylogenetic estimation problem. PMID:18005416

Catanzaro, Daniele; Pesenti, Rafflaele; Milinkovitch, Michel C

2007-01-01

368

REDESCRIPTION OF THE ANT LEPTOTHORAX (S. STR.) SCAMNI RUZSKY, 1905  

E-print Network

to be a rather rare, patchily distributed ant in alpine coniferous forests in the Caucasus (Russia and Armenia. str.) in Turkey (J. H., A. S.) and the Caucasus (A. G. R.), which exactly fit Ruzsky's description

Villemant, Claire

369

Efficient Egress of Escaping Ants Stressed with Temperature  

PubMed Central

In the present work we investigate the egress times of a group of Argentine ants (Linepithema humile) stressed with different heating speeds. We found that the higher the temperature ramp is, the faster ants evacuate showing, in this sense, a group-efficient evacuation strategy. It is important to note that even when the life of ants was in danger, jamming and clogging was not observed near the exit, in accordance with other experiments reported in the literature using citronella as aversive stimuli. Because of this clear difference between ants and humans, we recommend the use of some other animal models for studying competitive egress dynamics as a more accurate approach to understanding competitive egress in human systems. PMID:24312264

Boari, Santiago; Josens, Roxana; Parisi, Daniel R.

2013-01-01

370

9 CFR 354.121 - Ante-mortem inspection.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Ante-mortem inspection. 354.121 Section 354...Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION...

2011-01-01

371

9 CFR 354.121 - Ante-mortem inspection.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Ante-mortem inspection. 354.121 Section 354...Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION...

2013-01-01

372

9 CFR 354.121 - Ante-mortem inspection.  

...2014-01-01 false Ante-mortem inspection. 354.121 Section 354...Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION...

2014-01-01

373

9 CFR 354.121 - Ante-mortem inspection.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Ante-mortem inspection. 354.121 Section 354...Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION...

2010-01-01

374

9 CFR 354.121 - Ante-mortem inspection.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Ante-mortem inspection. 354.121 Section 354...Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION...

2012-01-01

375

9 CFR 352.10 - Ante-mortem inspection.  

Code of Federal Regulations, 2010 CFR

... (1) Reindeer, elk, deer, antelope, bison and water buffalo are eligible for field ante-mortem inspection. The...1) Reindeer, elk, deer, antelope, bison, and water buffalo are eligible for transport vehicle inspection....

2010-01-01

376

Disease Dynamics in a Specialized Parasite of Ant Societies  

PubMed Central

Coevolution between ant colonies and their rare specialized parasites are intriguing, because lethal infections of workers may correspond to tolerable chronic diseases of colonies, but the parasite adaptations that allow stable coexistence with ants are virtually unknown. We explore the trade-offs experienced by Ophiocordyceps parasites manipulating ants into dying in nearby graveyards. We used field data from Brazil and Thailand to parameterize and fit a model for the growth rate of graveyards. We show that parasite pressure is much lower than the abundance of ant cadavers suggests and that hyperparasites often castrate Ophiocordyceps. However, once fruiting bodies become sexually mature they appear robust. Such parasite life-history traits are consistent with iteroparity– a reproductive strategy rarely considered in fungi. We discuss how tropical habitats with high biodiversity of hyperparasites and high spore mortality has likely been crucial for the evolution and maintenance of iteroparity in parasites with low dispersal potential. PMID:22567151

Andersen, Sandra B.; Ferrari, Matthew; Evans, Harry C.; Elliot, Simon L.; Boomsma, Jacobus J.; Hughes, David P.

2012-01-01

377

9 CFR 352.10 - Ante-mortem inspection.  

Code of Federal Regulations, 2012 CFR

... (1) Reindeer, elk, deer, antelope, bison and water buffalo are eligible for field ante-mortem inspection. The...1) Reindeer, elk, deer, antelope, bison, and water buffalo are eligible for transport vehicle inspection....

2012-01-01

378

9 CFR 352.10 - Ante-mortem inspection.  

Code of Federal Regulations, 2013 CFR

... (1) Reindeer, elk, deer, antelope, bison and water buffalo are eligible for field ante-mortem inspection. The...1) Reindeer, elk, deer, antelope, bison, and water buffalo are eligible for transport vehicle inspection....

2013-01-01

379

9 CFR 352.10 - Ante-mortem inspection.  

... (1) Reindeer, elk, deer, antelope, bison and water buffalo are eligible for field ante-mortem inspection. The...1) Reindeer, elk, deer, antelope, bison, and water buffalo are eligible for transport vehicle inspection....

2014-01-01

380

9 CFR 352.10 - Ante-mortem inspection.  

Code of Federal Regulations, 2011 CFR

... (1) Reindeer, elk, deer, antelope, bison and water buffalo are eligible for field ante-mortem inspection. The...1) Reindeer, elk, deer, antelope, bison, and water buffalo are eligible for transport vehicle inspection....

2011-01-01

381

Ants of Ambon Island – diversity survey and checklist  

PubMed Central

Abstract The present checklist of ants (Hymenoptera: Formicidae) of Ambon is the first comprehensive overview of ant species recorded on the island during the last 150 years. The species list is based on literature and museum collections’ records combined with data from our field survey in 2010. In total, there are 74 ant species and subspecies representing 34 genera and six subfamilies known from Ambon. Five of the species found in undisturbed forest were exotic and indicate the overall habitat degradation on the island. The largest proportion of Ambon ant fauna are species with affinities to the Oriental region and species of Oriental-Austro-Melanesian origin. At least 20% of the species are regional endemics. In comparison to other islands in the region, the Ambon fauna seems more diverse and better sampled; however it is clear that a large part of it still remains to be described. PMID:25632248

Latumahina, Fransina; Borovanska, Michaela; Musyafa; Sumardi; Putra, Nugroho Susetya; Janda, Milan

2015-01-01

382

Introduction Ants are among the most ecologically diverse and  

E-print Network

to Drosophila fruit flies and Tribolium flour beetles, all sequenced ant and bee species have a complete set and wing polyphenism have fewer CpG sites, the main target sites of DNA methylation, than the genome

Alvarez, Nadir

383

ACPYPE - AnteChamber PYthon Parser interfacE  

E-print Network

AbstractBackgroundACPYPE (or AnteChamber PYthon Parser interfacE) is a wrapper script around the ANTECHAMBER software that simplifies the generation of small molecule topologies and parameters for a variety of molecular dynamics programmes like...

Sousa da Silva, Alan W; Vranken, Wim F

2012-07-23

384

Scope of Various Random Number Generators in ant System Approach for TSP  

NASA Technical Reports Server (NTRS)

Experimented on heuristic, based on an ant system approach for traveling salesman problem, are several quasi- and pseudo-random number generators. This experiment is to explore if any particular generator is most desirable. Such an experiment on large samples has the potential to rank the performance of the generators for the foregoing heuristic. This is mainly to seek an answer to the controversial issue "which generator is the best in terms of quality of the result (accuracy) as well as cost of producing the result (time/computational complexity) in a probabilistic/statistical sense."

Sen, S. K.; Shaykhian, Gholam Ali

2007-01-01

385

Social discrimination tuning in ants: template formation and chemical similarity  

Microsoft Academic Search

To investigate the role of template plasticity in shaping nest-mate recognition processes in ants, we constructed experimental\\u000a mixed-species groups of Manica rubida with either Myrmica rubra, Tetramorium bicarinatum or Formica selysi. Selecting Ma. rubida as the focal species, we observed the behaviour within mixed-species groups and the transfer rates of cuticular hydrocarbons\\u000a (CHC) onto the focal ants, and we also

Christine Errard; Abraham Hefetz; Pierre Jaisson

2006-01-01

386

Ant Mimicry by an Aphid Parasitoid, Lysiphlebus fabarum  

PubMed Central

In Iran, Lysiphlebus fabarum (Marshall) (Hymenoptera: Braconidae: Aphidiinae) is a uniparental parasitoid of the black bean aphid, Aphis fabae Scopoli (Hemiptera: Aphididae), that possesses various highly evolved adaptations for foraging within ant-tended aphid colonies. Direct observations and video recordings were used to analyze the behavior of individual females foraging for A. fabae on bean leaf disks in open arenas in the laboratory. Females exploited aphids as hosts and as a source of food, allocating within-patch time as follows: resting - 10.4%, grooming - 8.2%, searching - 11.5%, antennation (host recognition) - 7.5%, antennation (honeydew solicitation mimicking ants) - 31.9%, abdominal bending (attack preparation) 19.7%, probing with the ovipositor (attack) - 10.8%. The mean handling time for each aphid encountered was 2.0 ± 0.5 min. Females encountered an average of 47.4 ± 6.4 aphids per hour, but laid only 1.2 eggs per hour. The ovipositor insertion time for parasitism ranged from 2 sec to longer than a minute, but most insertions did not result in an egg being laid. A. fabae defensive behaviors included kicking, raising and swiveling the body, and attempts to smear the attacker with cornicle secretions, sometimes with lethal results. Food deprivation for 4–6 h prior to testing increased the frequency of ant mimcry by L. fabarum. Females also used ant-like antennation to reduce A. fabae defensive behavior, e.g. the frequency of kicking. L. fabarum attacks primed A. fabae to be more responsive to subsequent honeydew solicitation, such that experienced females improved their feeding success by alternating between the roles of parasitoid and ant mimic. These results reveal the possibility for mutualisms to evolve between L. fabarum and the ant species that tend A. fabae, since L. fabarum receive ant protection for their progeny and may benefit the ants by improving A. fabae responsiveness to honeydew solicitation. PMID:20879920

Rasekh, Arash; Michaud, J.P.; Kharazi-Pakdel, Aziz; Allahyari, Hossein

2010-01-01

387

Ant mimicry by an aphid parasitoid, Lysiphlebus fabarum.  

PubMed

In Iran, Lysiphlebus fabarum (Marshall) (Hymenoptera: Braconidae: Aphidiinae) is a uniparental parasitoid of the black bean aphid, Aphis fabae Scopoli (Hemiptera: Aphididae), that possesses various highly evolved adaptations for foraging within ant-tended aphid colonies. Direct observations and video recordings were used to analyze the behavior of individual females foraging for A. fabae on bean leaf disks in open arenas in the laboratory. Females exploited aphids as hosts and as a source of food, allocating within-patch time as follows: resting - 10.4%, grooming - 8.2%, searching - 11.5%, antennation (host recognition) - 7.5%, antennation (honeydew solicitation mimicking ants) - 31.9%, abdominal bending (attack preparation) 19.7%, probing with the ovipositor (attack) - 10.8%. The mean handling time for each aphid encountered was 2.0 ± 0.5 min. Females encountered an average of 47.4 ± 6.4 aphids per hour, but laid only 1.2 eggs per hour. The ovipositor insertion time for parasitism ranged from 2 sec to longer than a minute, but most insertions did not result in an egg being laid. A. fabae defensive behaviors included kicking, raising and swiveling the body, and attempts to smear the attacker with cornicle secretions, sometimes with lethal results. Food deprivation for 4-6 h prior to testing increased the frequency of ant mimcry by L. fabarum. Females also used ant-like antennation to reduce A. fabae defensive behavior, e.g. the frequency of kicking. L. fabarum attacks primed A. fabae to be more responsive to subsequent honeydew solicitation, such that experienced females improved their feeding success by alternating between the roles of parasitoid and ant mimic. These results reveal the possibility for mutualisms to evolve between L. fabarum and the ant species that tend A. fabae, since L. fabarum receive ant protection for their progeny and may benefit the ants by improving A. fabae responsiveness to honeydew solicitation. PMID:20879920

Rasekh, Arash; Michaud, J P; Kharazi-Pakdel, Aziz; Allahyari, Hossein

2010-01-01

388

Tracing the Rise of Ants -Out of the Ground Andrea Lucky1,2  

E-print Network

Tracing the Rise of Ants - Out of the Ground Andrea Lucky1,2 *, Michelle D. Trautwein3,4 , Benoit S The evolution of ants (Hymenoptera: Formicidae) is increasingly well-understood due to recent phylogenetic regarding the ancestral habitat of ants conflict with new findings that early ant lineages are cryptic

Lucky, Andrea

389

Spatial Distribution of Dominant Arboreal Ants in a Malagasy Coastal Rainforest: Gaps and Presence of an  

E-print Network

Spatial Distribution of Dominant Arboreal Ants in a Malagasy Coastal Rainforest: Gaps and Presence at increasing distances from the coast to determine whether a non-random arboreal ant assemblage, such as an ant populous colonies of territorially dominant arboreal ant species defend absolute territories distributed

Paris-Sud XI, Université de

390

Ant Routing in Mobile Ad Hoc Networks S. S. Dhillon, X. Arbona and P. Van Mieghem  

E-print Network

Ant Routing in Mobile Ad Hoc Networks S. S. Dhillon, X. Arbona and P. Van Mieghem Delft University the performance of ant routing for static and dynamic network topologies. We also compare the per- formance of ant routing with AODV and DSR for ad hoc networks. The simulations show that the ant routing al- gorithm

Van Mieghem, Piet

391

Health Hazards of Imported Fire Fire ants are stinging insects that belong to the same  

E-print Network

Health Hazards of Imported Fire Ant Stings Background Fire ants are stinging insects that belong to the same order as bees and wasps. The red-black imported fire ant now infests more than 260 million acres hazard. Fire ant mounds may measure up to three feet in diameter and 18 inches in height. Each mound may

Balasundaram, Balabhaskar "Baski"

392

Antaphid mutualism: the influence of ants on the aphid summer cycle  

E-print Network

61 Ant­aphid mutualism: the influence of ants on the aphid summer cycle Karolina Tegelaar, Mattias on the effects on aphids of being tended by ants. The aim of this study is to investigate how the presence of ants influences settling decisions by colonizing aphids and the post-settlement growth and survival

Leimar, Olof

393

Deterrency and Toxicity of Essential Oils to Argentine and Red Imported Fire Ants (Hymenoptera: Formicidae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Laboratory assays were conducted to evaluate deterrency and contact toxicity of six essential oils to the Argentine ant, Linepithema humile (Mayr), and the red imported fire ant, Solenopsis invicta Buren. In choice tests, both Argentine ants and fire ants crossed barriers treated with multiple rates...

394

ANT-GARDEN EPIPHYTES ARE PROTECTED AGAINST DROUGHT IN A VENEZUELAN LOWLAND RAIN FOREST  

Microsoft Academic Search

Neotropical ant gardens (AGs) represent a classic mutualism between ants and epiphytic plants. Previous studies showed that these plants benefit from effective fruit dispersal and improved nutrition provided by gardening ants. Here we show an additional positive impact of gardening ants and their substrate on the fitness and survival of the AG epiphyte Peperomia macrostachya (Piperaceae) and seedlings of other

Viviane Schmit-Neuerburg; Nico Blüthgen

395

Adapting an Ant Colony Metaphor for Multi-Robot Chemical Plume Tracing  

PubMed Central

We consider chemical plume tracing (CPT) in time-varying airflow environments using multiple mobile robots. The purpose of CPT is to approach a gas source with a previously unknown location in a given area. Therefore, the CPT could be considered as a dynamic optimization problem in continuous domains. The traditional ant colony optimization (ACO) algorithm has been successfully used for combinatorial optimization problems in discrete domains. To adapt the ant colony metaphor to the multi-robot CPT problem, the two-dimension continuous search area is discretized into grids and the virtual pheromone is updated according to both the gas concentration and wind information. To prevent the adapted ACO algorithm from being prematurely trapped in a local optimum, the upwind surge behavior is adopted by the robots with relatively higher gas concentration in order to explore more areas. The spiral surge (SS) algorithm is also examined for comparison. Experimental results using multiple real robots in two indoor natural ventilated airflow environments show that the proposed CPT method performs better than the SS algorithm. The simulation results for large-scale advection-diffusion plume environments show that the proposed method could also work in outdoor meandering plume environments. PMID:22666056

Meng, Qing-Hao; Yang, Wei-Xing; Wang, Yang; Li, Fei; Zeng, Ming

2012-01-01

396

Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging  

USGS Publications Warehouse

Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

2010-01-01

397

Water Stress Strengthens Mutualism Among Ants, Trees, and Scale Insects  

PubMed Central

Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant–plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant–plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism. PMID:24223521

Pringle, Elizabeth G.; Akçay, Erol; Raab, Ted K.; Dirzo, Rodolfo; Gordon, Deborah M.

2013-01-01

398

Ant Colonies Prefer Infected over Uninfected Nest Sites  

PubMed Central

During colony relocation, the selection of a new nest involves exploration and assessment of potential sites followed by colony movement on the basis of a collective decision making process. Hygiene and pathogen load of the potential nest sites are factors worker scouts might evaluate, given the high risk of epidemics in group-living animals. Choosing nest sites free of pathogens is hypothesized to be highly efficient in invasive ants as each of their introduced populations is often an open network of nests exchanging individuals (unicolonial) with frequent relocation into new nest sites and low genetic diversity, likely making these species particularly vulnerable to parasites and diseases. We investigated the nest site preference of the invasive pharaoh ant, Monomorium pharaonis, through binary choice tests between three nest types: nests containing dead nestmates overgrown with sporulating mycelium of the entomopathogenic fungus Metarhizium brunneum (infected nests), nests containing nestmates killed by freezing (uninfected nests), and empty nests. In contrast to the expectation pharaoh ant colonies preferentially (84%) moved into the infected nest when presented with the choice of an infected and an uninfected nest. The ants had an intermediate preference for empty nests. Pharaoh ants display an overall preference for infected nests during colony relocation. While we cannot rule out that the ants are actually manipulated by the pathogen, we propose that this preference might be an adaptive strategy by the host to “immunize” the colony against future exposure to the same pathogenic fungus. PMID:25372856

Pontieri, Luigi; Vojvodic, Svjetlana; Graham, Riley; Pedersen, Jes Søe; Linksvayer, Timothy A.

2014-01-01

399

Colony Fusion in a Parthenogenetic Ant, Pristomyrmex punctatus  

PubMed Central

In the ant Pristomyrmex punctatus Smith (Hymenoptera: Formicidae), all young workers lay a small number of eggs parthenogenetically. Some colonies consist of monoclonal individuals that provide high inclusive fitness, according to the kin selection theory. However, in some populations, a majority of the colonies contain multiple lineages. Intracolonial genetic variation of parthenogenetic ants cannot be explained by the multiple mating of single founderesses or by the foundation of a colony by multiple foundresses, which are the usual causes of genetically diverse colonies in social insects. Here, we hypothesized that the fusion of established colonies might facilitate the formation of multiclonal colonies. Colony fusion decreases indirect benefits because of the reduction in intracolonial relatedness. However, when suitable nesting places for overwintering are scarce, colony fusion provides a strategy for the survival of colonies. Here, ants derived from different colonies were allowed to encounter one another in a container with just one nesting place. Initially, high aggression was observed; however, after several days, no aggression was observed and the ants shared the nest. When the fused colonies were allowed to transfer to two alternative nests, ants from different colonies occupied the same nest. This study highlights the importance of limiting the number of nesting places in order to understand the genetic diversity of parthenogenetic ant colonies. PMID:23895053

Satow, Show; Satoh, Toshiyuki; Hirota, Tadao

2013-01-01

400

Colony fusion in a parthenogenetic ant, Pristomyrmex punctatus.  

PubMed

In the ant Pristomyrmex punctatus Smith (Hymenoptera: Formicidae), all young workers lay a small number of eggs parthenogenetically. Some colonies consist of monoclonal individuals that provide high inclusive fitness, according to the kin selection theory. However, in some populations, a majority of the colonies contain multiple lineages. Intracolonial genetic variation of parthenogenetic ants cannot be explained by the multiple mating of single founderesses or by the foundation of a colony by multiple foundresses, which are the usual causes of genetically diverse colonies in social insects. Here, we hypothesized that the fusion of established colonies might facilitate the formation of multiclonal colonies. Colony fusion decreases indirect benefits because of the reduction in intracolonial relatedness. However, when suitable nesting places for overwintering are scarce, colony fusion provides a strategy for the survival of colonies. Here, ants derived from different colonies were allowed to encounter one another in a container with just one nesting place. Initially, high aggression was observed; however, after several days, no aggression was observed and the ants shared the nest. When the fused colonies were allowed to transfer to two alternative nests, ants from different colonies occupied the same nest. This study highlights the importance of limiting the number of nesting places in order to understand the genetic diversity of parthenogenetic ant colonies. PMID:23895053

Satow, Show; Satoh, Toshiyuki; Hirota, Tadao

2013-01-01

401

The Morphometry of Solenopsis Fire Ants  

PubMed Central

Size-related changes of body shape were explored in 15 polymorphic species of Solenopsis fire ants by analyzing body weight along with linear measurements of 24 body parts. Log regression slopes were used to detect changes of shape with increasing size. Within species, the largest workers weighed from about 5 to 30-fold as much as the smallest. The range of within-species body lengths varied from 1.6 mm to 4 mm. As worker size increased, the gaster tended to make up a larger proportion of body length, usually at the cost of the petiole, and rarely at the cost of head length or mesosoma length. In most, the relative volume of the gaster increased and that of the head and mesosoma decreased. Most also showed an increasingly “humped” mesosoma. For all species, head shape changed from barrel-shaped to heart-shaped as worker size increased. Antennae became relatively shorter as the relative size of the club decreased. Shape changes of the legs were more variable. S. geminata was exceptional in the extreme nature of its head shape change, and was the only species in which relative head volume increased and gaster volume decreased with increasing body size. With the exception of S. geminata, the allometric rules governing shape are remarkably similar across species, suggesting a genus-level developmental scheme that is not easily modified by evolution. It also suggests that the evolution of shape is highly constrained by these conserved growth rules, and that it acts primarily (perhaps only) through allometric growth. The results are discussed in light of the growth of imaginal discs in a resource-limited body (the pupa). The substantial variation of allometries within species and across localities is also discussed in relation to using allometric patterns to identify species or to construct phylogenies. PMID:24260250

Tschinkel, Walter R.

2013-01-01

402

Vegetation of ant-hills in a mountain grassland:effects of mound history and of dominant ant species  

Microsoft Academic Search

Vegetation in grasslands with well-developed long-lastingant-hills in the Slovenské Rudohorie Mts., Slovakia, was studiedin relation to (i) position on the mound, (ii) ant speciesforming the mound, and (iii) history of the mound. Permanent plotrecordings of mound size and dominant ant species started fifteen years priorthe study began provided information on the history of individual mounds.The mound vegetation bears a striking

Pavel Ková?; Marcela Ková?ová; Petr Dostál; TomᚠHerben

2001-01-01

403

First fossil record of nematode parasitism of ants; a 40 million year tale.  

PubMed

A mermithid nematode emerging from a male ant, Prenolepis henschei Mayr, in Baltic amber is the first fossil record demonstrating nematode parasitism of ants. This parasite, described as Heydeniusformicinus sp. n., is compared to extant mermithid parasites of ants, especially Allomermis myrmecophila Baylis 1921. The present fossil, together with earlier reports of braconid and mite parasitism of ants in Baltic amber, indicates that several diverse groups had already evolved parasitic associations with ants by the Eocene. PMID:12458829

Poinar, G

2002-11-01

404

Effect of Argentine ant invasions on ground-dwelling arthropods in northern California riparian woodlands  

Microsoft Academic Search

Although the Argentine ant (Linepithema humile) is a widespread invasive species that displaces native ants throughout its introduced range, the effects of these invasions\\u000a on arthropods other than ants remain poorly known. This study documents the consequences of Argentine ant invasions on ants\\u000a and other ground-dwelling arthropods in northern California riparian woodlands. Baits and unbaited pitfall traps were used\\u000a to

David A. Holway

1998-01-01

405

Foraging ants trade off further for faster: use of natural bridges and trunk trail permanency in carpenter ants  

NASA Astrophysics Data System (ADS)

Trail-making ants lay pheromones on the substrate to define paths between foraging areas and the nest. Combined with the chemistry of these pheromone trails and the physics of evaporation, trail-laying and trail-following behaviours provide ant colonies with the quickest routes to food. In relatively uniform environments, such as that provided in many laboratory studies of trail-making ants, the quickest route is also often the shortest route. Here, we show that carpenter ants ( Camponotus rufipes), in natural conditions, are able to make use of apparent obstacles in their environment to assist in finding the fastest routes to food. These ants make extensive use of fallen branches, twigs and lianas as bridges to build their trails. These bridges make trails significantly longer than their straight line equivalents across the forest floor, but we estimate that ants spend less than half the time to reach the same point, due to increased carriage speed across the bridges. We also found that these trails, mainly composed of bridges, are maintained for months, so they can be characterized as trunk trails. We suggest that pheromone-based foraging trail networks in field conditions are likely to be structured by a range of potentially complex factors but that even then, speed remains the most important consideration.

Loreto, Raquel G.; Hart, Adam G.; Pereira, Thairine M.; Freitas, Mayara L. R.; Hughes, David P.; Elliot, Simon L.

2013-10-01

406

Foraging ants trade off further for faster: use of natural bridges and trunk trail permanency in carpenter ants.  

PubMed

Trail-making ants lay pheromones on the substrate to define paths between foraging areas and the nest. Combined with the chemistry of these pheromone trails and the physics of evaporation, trail-laying and trail-following behaviours provide ant colonies with the quickest routes to food. In relatively uniform environments, such as that provided in many laboratory studies of trail-making ants, the quickest route is also often the shortest route. Here, we show that carpenter ants (Camponotus rufipes), in natural conditions, are able to make use of apparent obstacles in their environment to assist in finding the fastest routes to food. These ants make extensive use of fallen branches, twigs and lianas as bridges to build their trails. These bridges make trails significantly longer than their straight line equivalents across the forest floor, but we estimate that ants spend less than half the time to reach the same point, due to increased carriage speed across the bridges. We also found that these trails, mainly composed of bridges, are maintained for months, so they can be characterized as trunk trails. We suggest that pheromone-based foraging trail networks in field conditions are likely to be structured by a range of potentially complex factors but that even then, speed remains the most important consideration. PMID:24022667

Loreto, Raquel G; Hart, Adam G; Pereira, Thairine M; Freitas, Mayara L R; Hughes, David P; Elliot, Simon L

2013-10-01

407

Network Formation Using Ant Colony Optimization  

Microsoft Academic Search

A significant area of research in the field of hybrid communications is the Network Design Problem (NDP) [1]. The NDP is an\\u000a NP complete problem [1] that focuses on identifying the optimal network topology for transmitting commodities between nodes,\\u000a under constraints such as bandwidth, limited compatible directed channels, and link and commodity costs. The NDP focuses on\\u000a designing a flexible

Steven C. Oimoen; Gilbert L. Peterson; Kenneth M. Hopkinson

2008-01-01

408

Catching ants with honey: an experimental test of distraction and satiation as alternative modes of escape from flower-damaging ants.  

PubMed

According to the distraction hypothesis, extrafloral nectaries (EFN) evolved under selection to entice ants away from floral nectaries, reducing ant-mediated damage to flowers and/or interference with pollinators. Predator-satiation, through production of nectar in either surplus flowers or EFN, provides an alternative mechanism for reducing the impact of ants as flower visitors. I tested these two hypotheses by experimentally adding EFN to flowering plants of the alpine wildflower, Polemonium viscosum, and by surveying the relationship between ant visitation and nectary number in nature. Plants of P. viscosum lack EFN and experience flower damage by ants of Formica neorufibarbus gelida. Ant behavior was compared on plants with five flowers and three experimental EFN and on controls with equal floral display, but no EFN. Addition of EFN increased flower visitation by ants. The effect of EFN on flower visitation did not depend on proximity of EFN to flowers or attractiveness of EFN to ants. Findings suggest that ants perceived patch quality on a whole plant basis, rather than responding to EFN and flowers as distinct nectar patches. Ant visitation did not keep pace with nectary number in nature. The relationship between ant visitation and nectary number per plant was weak and shallow as predicted under satiation. Ant foraging choices on experimental inflorescences showed that ants bypass flowers avoided by earlier ants, enhancing probability of escape via satiation. Results do not support the idea that EFN evolve to reduce flower visitation by ants, but show instead that nectar in surplus flowers can satiate ants and reduce their negative impacts on flower function and integrity. PMID:15800742

Galen, Candace

2005-06-01

409

Honey, I Shrunk The Windmills! To The Size OfHoney, I Shrunk The Windmills! To The Size Of An AntAn Ant  

E-print Network

An Ant BY LAUREN SILVERMAN (HTTP://BREAKTHROUGHS.KERA.ORG/AUTHOR/LAUREN-SILVERMAN/) July 30th, 2014 | 6!Honey, I Shrunk The Windmills! To The Size Of An AntTo The Size Of An Ant (http://breakthroughs.kera.org/m(http://breakthroughs Risk: Take Your PulseStroke Risk: Take Your Pulse (http://breakthroughs.kera.org/np(http://breakthroughs

Chiao, Jung-Chih

410

Field Trapping the Little Fire Ant, Wasmannia auropunctata  

PubMed Central

Two detection methods for the little fire ant, Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae), both employing the pheromone attractant 2,5-dimethyl-3-(2-methylbutyl)pyrazine (2-MeBu-diMePy), were compared with peanut butter based detection, in order to evaluate differences in species specificity and detection reliability. Trapping was conducted using a transect through a macadamia orchard on the island of Hawaii. The transect consisted of a series of three-tree plots, each plot contained a peanut butter coated stick (the most common detection method used for W. auropunctata in Hawaii), a one—way trap treated with 2-MeBu-diMePy, and a piece of double-sided tape treated with 2-MeBu-diMePy. While there were no differences in the number of W. auropunctata counted with each detection method, and no differences in detection reliability (detecting the known presence of W. auropunctata in a plot), the pheromone—incorporating methods showed greater species specificity, retaining W. auropunctata almost exclusively. These results demonstrate the potential of pheromone—detection methods to selectively capture target ant species even when other ants are present and abundant. Combined data from all three detection methods and a previous visual survey along the transect showed a marked difference in the frequency of cohabitation among ant species. Of the 10 ant species collected, W. auropunctata was found as the sole ant species on a given tree at a significantly higher frequency than all other ant species except Pheidole fervens. 94% percent of the trees with W. auropunctata had only W. auropunctata, supporting previous observations that this species tends to displace other ant species. In addition, W. auropunctata microhabitat preferences were investigated using one—way traps containing 2-MeBu-diMePy, which were placed in three arboreal and three non—arboreal locations. While the number of ants captured did not differ by trap placement, when grouped, captures were significantly higher in arboreal than non-arboreal microhabitats. PMID:23421782

Derstine, Nathan T.; Troyer, Elisa J.; Suttles, Caitlyn N.; Siderhurst, Leigh A.; Jang, Eric B.; Siderhurst, Matthew S.

2012-01-01

411

Search strategies of ants in landmark-rich habitats.  

PubMed

Search is an important tool in an ant's navigational toolbox to relocate food sources and find the inconspicuous nest entrance. In habitats where landmark information is sparse, homing ants travel their entire home vector before searching systematically with ever increasing loops. Search strategies have not been previously investigated in ants that inhabit landmark-rich habitats where they typically establish stereotypical routes. Here we examine the search strategy in one such ant, Melophorus bagoti, by confining their foraging in one-dimensional channels to determine if their search pattern changes with experience, location of distant cues and altered distance on the homebound journey. Irrespective of conditions, we found ants exhibit a progressive search that drifted towards the fictive nest and beyond. Segments moving away from the start of the homeward journey were longer than segments heading back towards the start. The right tail distribution of segment lengths was well fitted by a power function, but slopes less than -3 on a log-log plot indicate that the process cannot be characterized as Lévy searches that have optimal slopes near -2. A double exponential function fits the distribution of segment lengths better, supporting another theoretically optimal search pattern, the composite Brownian walk. PMID:18781312

Narendra, Ajay; Cheng, Ken; Sulikowski, Danielle; Wehner, Rüdiger

2008-11-01

412

Immune priming and pathogen resistance in ant queens  

PubMed Central

Growing empirical evidence indicates that invertebrates become more resistant to a pathogen following initial exposure to a nonlethal dose; yet the generality, mechanisms, and adaptive value of such immune priming are still under debate. Because life-history theory predicts that immune priming and large investment in immunity should be more frequent in long-lived species, we here tested for immune priming and pathogen resistance in ant queens, which have extraordinarily long life span. We exposed virgin and mated queens of Lasius niger and Formica selysi to a low dose of the entomopathogenic fungus Beauveria bassiana, before challenging them with a high dose of the same pathogen. We found evidence for immune priming in naturally mated queens of L. niger. In contrast, we found no sign of priming in virgin queens of L. niger, nor in virgin or experimentally mated queens of F. selysi, which indicates that immune priming in ant queens varies according to mating status and mating conditions or species. In both ant species, mated queens showed higher pathogen resistance than virgin queens, which suggests that mating triggers an up-regulation of the immune system. Overall, mated ant queens combine high reproductive output, very long life span, and elevated investment in immune defense. Hence, ant queens are able to invest heavily in both reproduction and maintenance, which can be explained by the fact that mature queens will be protected and nourished by their worker offspring. PMID:24963375

Gálvez, Dumas; Chapuisat, Michel

2014-01-01

413

Catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria  

PubMed Central

Abstract The present catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria is made on a base of critical reconsideration of literature (covering the period from 1892 till 2009 and part of 2010) as well as on examination of the authors‘ and several museum‘s collections. A lot of data were omitted in the previous Bulgarian monograph on ants, lots of new data were recently added and many important additions and alterations were made due to taxonomic revisions of Eurasian Formicidae during the last three decades. Two new species are reported for the country [Temnothorax graecus (Forel, 1911) and Temnothorax cf. korbi (Emery, 1924)]. This catalogue contains a list of 163 ant species belonging to 40 genera of 6 subfamilies now known from Bulgaria. Synonyms and information on the previously reported names in relevant publications are given. Known localities of the species are grouped by geographic regions. Maps with concrete localities or regions for each species were prepared. The conservation status of 13 ant species is given as they are included in IUCN Red List of Threatened Species and Bulgarian Biodiversity Act. In comparison with adjacent Balkan regions the ant fauna of Bulgaria is quite rich and its core is composed of South European elements. PMID:21594018

Lapeva-Gjonova, Albena; Antonova, Vera; Radchenko, Alexander G.; Atanasova, Maria

2010-01-01

414

Prey Capture Behavior in an Arboreal African Ponerine Ant  

PubMed Central

I studied the predatory behavior of Platythyrea conradti, an arboreal ponerine ant, whereas most species in this subfamily are ground-dwelling. The workers, which hunt solitarily only around dusk, are able to capture a wide range of prey, including termites and agile, nocturnal insects as well as diurnal insects that are inactive at that moment of the Nyctemeron, resting on tree branches or under leaves. Prey are captured very rapidly, and the antennal palpation used by ground-dwelling ponerine species is reduced to a simple contact; stinging occurs immediately thereafter. The venom has an instant, violent effect as even large prey (up to 30 times the weight of a worker) never struggled after being stung. Only small prey are not stung. Workers retrieve their prey, even large items, singly. To capture termite workers and soldiers defending their nest entrances, ant workers crouch and fold their antennae backward. In their role as guards, the termites face the crouching ants and end up by rolling onto their backs, their legs batting the air. This is likely due to volatile secretions produced by the ants' mandibular gland. The same behavior is used against competing ants, including territorially-dominant arboreal species that retreat further and further away, so that the P. conradti finally drive them from large, sugary food sources. PMID:21589941

Dejean, Alain

2011-01-01

415

Visual Navigation during Colony Emigration by the Ant Temnothorax rugatulus  

PubMed Central

Many ants rely on both visual cues and self-generated chemical signals for navigation, but their relative importance varies across species and context. We evaluated the roles of both modalities during colony emigration by Temnothorax rugatulus. Colonies were induced to move from an old nest in the center of an arena to a new nest at the arena edge. In the midst of the emigration the arena floor was rotated 60°around the old nest entrance, thus displacing any substrate-bound odor cues while leaving visual cues unchanged. This manipulation had no effect on orientation, suggesting little influence of substrate cues on navigation. When this rotation was accompanied by the blocking of most visual cues, the ants became highly disoriented, suggesting that they did not fall back on substrate cues even when deprived of visual information. Finally, when the substrate was left in place but the visual surround was rotated, the ants' subsequent headings were strongly rotated in the same direction, showing a clear role for visual navigation. Combined with earlier studies, these results suggest that chemical signals deposited by Temnothorax ants serve more for marking of familiar territory than for orientation. The ants instead navigate visually, showing the importance of this modality even for species with small eyes and coarse visual acuity. PMID:23671713

Bowens, Sean R.; Glatt, Daniel P.; Pratt, Stephen C.

2013-01-01

416

A novel property of spider silk: chemical defence against ants  

PubMed Central

Spider webs are made of silk, the properties of which ensure remarkable efficiency at capturing prey. However, remaining on, or near, the web exposes the resident spiders to many potential predators, such as ants. Surprisingly, ants are rarely reported foraging on the webs of orb-weaving spiders, despite the formidable capacity of ants to subdue prey and repel enemies, the diversity and abundance of orb-web spiders, and the nutritional value of the web and resident spider. We explain this paradox by reporting a novel property of the silk produced by the orb-web spider Nephila antipodiana (Walckenaer). These spiders deposit on the silk a pyrrolidine alkaloid (2-pyrrolidinone) that provides protection from ant invasion. Furthermore, the ontogenetic change in the production of 2-pyrrolidinone suggests that this compound represents an adaptive response to the threat of natural enemies, rather than a simple by-product of silk synthesis: while 2-pyrrolidinone occurs on the silk threads produced by adult and large juvenile spiders, it is absent on threads produced by small juvenile spiders, whose threads are sufficiently thin to be inaccessible to ants. PMID:22113027

Zhang, Shichang; Koh, Teck Hui; Seah, Wee Khee; Lai, Yee Hing; Elgar, Mark A.; Li, Daiqin

2012-01-01

417

New records of ant species from Yunnan, China  

PubMed Central

Abstract As with many other regions of the world, significant collecting, curation, and taxonomic efforts will be needed to complete the inventory of China’s ant fauna. This is especially true for the highly diverse tropical regions in the south of the country, where moist tropical forests harbor high species richness typical of the Southeast Asian region. We inventoried ants in the Xingshuangbanna prefecture, Yunnan, in June 2013, using a variety of methods including Winkler extraction and hand collection to sample ant diversity. We identified 213 species/morphospecies of ants from 10 subfamilies and 61 genera. After identification of 148 valid species of the 213 total species collected, 40 species represent new records for Yunnan province and 17 species are newly recorded for China. This increases the total number of named ant species in Yunnan and China to 447 and 951 respectively. The most common species collected were Brachyponera luteipes and Vollenhovia emeryi. Only one confirmed exotic species Strumigenys membranifera, was collected, although several others were potentially introduced by humans. These results highlight the high biodiversity value of the region, but also underscore how much work remains to fully document the native myrmecofauna.

Liu, Cong; Guénard, Benoit; Garcia, Francisco Hita; Yamane, Seiki; Blanchard, Benjamin; Yang, Da-Rong; Economo, Evan

2015-01-01

418

New records of ant species from Yunnan, China.  

PubMed

As with many other regions of the world, significant collecting, curation, and taxonomic efforts will be needed to complete the inventory of China's ant fauna. This is especially true for the highly diverse tropical regions in the south of the country, where moist tropical forests harbor high species richness typical of the Southeast Asian region. We inventoried ants in the Xingshuangbanna prefecture, Yunnan, in June 2013, using a variety of methods including Winkler extraction and hand collection to sample ant diversity. We identified 213 species/morphospecies of ants from 10 subfamilies and 61 genera. After identification of 148 valid species of the 213 total species collected, 40 species represent new records for Yunnan province and 17 species are newly recorded for China. This increases the total number of named ant species in Yunnan and China to 447 and 951 respectively. The most common species collected were Brachyponeraluteipes and Vollenhoviaemeryi. Only one confirmed exotic species Strumigenysmembranifera, was collected, although several others were potentially introduced by humans. These results highlight the high biodiversity value of the region, but also underscore how much work remains to fully document the native myrmecofauna. PMID:25685004

Liu, Cong; Guénard, Benoit; Garcia, Francisco Hita; Yamane, Seiki; Blanchard, Benjamin; Yang, Da-Rong; Economo, Evan

2015-01-01

419

An ancient tripartite symbiosis of plants, ants and scale insects  

PubMed Central

In the Asian tropics, a conspicuous radiation of Macaranga plants is inhabited by obligately associated Crematogaster ants tending Coccus (Coccidae) scale insects, forming a tripartite symbiosis. Recent phylogenetic studies have shown that the plants and the ants have been codiversifying over the past 16–20 million years (Myr). The prevalence of coccoids in ant–plant mutualisms suggest that they play an important role in the evolution of ant–plant symbioses. To determine whether the scale insects were involved in the evolutionary origin of the mutualism between Macaranga and Crematogaster, we constructed a cytochrome oxidase I (COI) gene phylogeny of the scale insects collected from myrmecophytic Macaranga and estimated their time of origin based on a COI molecular clock. The minimum age of the associated Coccus was estimated to be half that of the ants, at 7–9?Myr, suggesting that they were latecomers in the evolutionary history of the symbiosis. Crematogaster mitochondrial DNA (mtDNA) lineages did not exhibit specificity towards Coccus mtDNA lineages, and the latter was not found to be specific towards Macaranga taxa, suggesting that patterns of associations in the scale insects are dictated by opportunity rather than by specialized adaptations to host plant traits. PMID:18611850

Ueda, Shouhei; Quek, Swee-Peck; Itioka, Takao; Inamori, Keita; Sato, Yumiko; Murase, Kaori; Itino, Takao

2008-01-01

420

Multi-trait mimicry of ants by a parasitoid wasp.  

PubMed

Many animals avoid attack from predators through toxicity or the emission of repellent chemicals. Defensive mimicry has evolved in many species to deceive shared predators, for instance through colouration and other morphological adaptations, but mimicry hardly ever seems to involve multi-trait similarities. Here we report on a wingless parasitoid wasp that exhibits a full spectrum of traits mimicing ants and affording protection against ground-dwelling predators (wolf spiders). In body size, morphology and movement Gelis agilis (Ichneumonidae) is highly similar to the black garden ant (Lasius niger) that shares the same habitat. When threatened, G. agilis also emits a volatile chemical that is similar to an ant-produced chemical that repels spiders. In bioassays with L. niger, G. agilis, G. areator, Cotesia glomerata and Drosophila melanogaster, ants and G. agilis were virtually immune to spider attack, in contrast the other species were not. Volatile characterisation with gas chromatography-mass spectrometry identified G. agilis emissions as 6-methyl-5-hepten-2-one, a known insect defence semiochemical that acts as an alarm pheromone in ants. We argue that multi-trait mimicry, as observed in G. agilis, might be much more common among animals than currently realized. PMID:25622726

Malcicka, Miriama; Bezemer, T Martijn; Visser, Bertanne; Bloemberg, Mark; Snart, Charles J P; Hardy, Ian C W; Harvey, Jeffrey A

2015-01-01

421

Ancient butterfly-ant symbiosis: direct evidence from Dominican amber  

PubMed Central

Although symbiotic association with ants is pervasive in the butterfly families Lycaenidae and Riodinidae the age of these symbioses has never been estimated explicitly. Here we report the first known fossil riodinid caterpillar. This fossil can be dated minimally between 15 and 20 Ma old, and confidently placed in the extant genus Theope. Differing little from modern day Theope, this fossil from Dominican amber provides direct evidence that secretory and acoustical organs used by modern caterpillars to mediate symbioses with ants have been highly developed at least since the Miocene. This fossil therefore becomes the point of reference for future studies using molecular clock methods for dating these symbioses within the riodinid butterflies. Modern evidence, and the abundance of dolichoderine ants in Dominican amber (now extinct in the West Indies) imply that specialized symbiotic relationships between Theope caterpillars and these ants were likely in existence at least 15 Ma ago. The current distribution of neotropical riodinid butterfly and ant faunas indicates the extinction in the West Indies of at least two unrelated taxa that formed a tightly linked symbiotic association, which persisted to the present elsewhere.

Devries, P. J.; Poinar, G. O.

1997-01-01

422

Endophytic fungi reduce leaf-cutting ant damage to seedlings.  

PubMed

Our study examines how the mutualism between Atta colombica leaf-cutting ants and their cultivated fungus is influenced by the presence of diverse foliar endophytic fungi (endophytes) at high densities in tropical leaf tissues. We conducted laboratory choice trials in which ant colonies chose between Cordia alliodora seedlings with high (E(high)) or low (E(low)) densities of endophytes. The E(high) seedlings contained 5.5 times higher endophyte content and a greater diversity of fungal morphospecies than the E(low) treatment, and endophyte content was not correlated with leaf toughness or thickness. Leaf-cutting ants cut over 2.5 times the leaf area from E(low) relative to E(high) seedlings and had a tendency to recruit more ants to E(low) plants. Our findings suggest that leaf-cutting ants may incur costs from cutting and processing leaves with high endophyte loads, which could impact Neotropical forests by causing variable damage rates within plant communities. PMID:20610420

Bittleston, L S; Brockmann, F; Wcislo, W; Van Bael, S A

2011-02-23

423

Multi-trait mimicry of ants by a parasitoid wasp  

PubMed Central

Many animals avoid attack from predators through toxicity or the emission of repellent chemicals. Defensive mimicry has evolved in many species to deceive shared predators, for instance through colouration and other morphological adaptations, but mimicry hardly ever seems to involve multi-trait similarities. Here we report on a wingless parasitoid wasp that exhibits a full spectrum of traits mimicing ants and affording protection against ground-dwelling predators (wolf spiders). In body size, morphology and movement Gelis agilis (Ichneumonidae) is highly similar to the black garden ant (Lasius niger) that shares the same habitat. When threatened, G. agilis also emits a volatile chemical that is similar to an ant-produced chemical that repels spiders. In bioassays with L. niger, G. agilis, G. areator, Cotesia glomerata and Drosophila melanogaster, ants and G. agilis were virtually immune to spider attack, in contrast the other species were not. Volatile characterisation with gas chromatography-mass spectrometry identified G. agilis emissions as 6-methyl-5-hepten-2-one, a known insect defence semiochemical that acts as an alarm pheromone in ants. We argue that multi-trait mimicry, as observed in G. agilis, might be much more common among animals than currently realized. PMID:25622726

Malcicka, Miriama; Bezemer, T. Martijn; Visser, Bertanne; Bloemberg, Mark; Snart, Charles J. P.; Hardy, Ian C. W.; Harvey, Jeffrey A.

2015-01-01

424

Ant System: An Autocatalytic Optimizing Process  

Microsoft Academic Search

A combination of distributed computation, positive feedback and constructive greedy heuristic is proposed as a new approach to stochastic optimization and problem solving. Positive feedback accounts for rapid discovery of very good solutions, distributed computation avoids premature convergence, and greedy heuristic helps the procedure to find acceptable solutions in the early stages of the search process. An application of the

M. Dorigo; V. Maniezzo; A. Colorni

1991-01-01

425

Solving the Generalized Vehicle Routing Problem with an ACS-based Algorithm  

NASA Astrophysics Data System (ADS)

Ant colony system is a metaheuristic algorithm inspired by the behavior of real ants and was proposed by Dorigo et al. as a method for solving hard combinatorial optimization problems. In this paper we show its successful application to solving a network design problem: Generalized Vehicle Routing Problem. The Generalized Vehicle Routing Problem (GVRP) is the problem of designing optimal delivery or collection routes, subject to capacity restrictions, from a given depot to a number of predefined, mutually exclusive and exhaustive clusters. Computational results for several benchmark problems are reported.

Pop, Petrica Claudiu; Pintea, Camelia; Zelina, Ioana; Dumitrescu, Dan

2009-04-01

426

Convergent genetic architecture underlies social organization in ants.  

PubMed

Complex adaptive polymorphisms are common in nature, but what mechanisms maintain the underlying favorable allelic combinations? The convergent evolution of polymorphic social organization in two independent ant species provides a great opportunity to investigate how genomes evolved under parallel selection. Here, we demonstrate that a large, nonrecombining "social chromosome" is associated with social organization in the Alpine silver ant, Formica selysi. This social chromosome shares architectural characteristics with that of the fire ant Solenopsis invicta, but the two show no detectable similarity in gene content. The discovery of convergence at two levels--the phenotype and the genetic architecture associated with alternative social forms--points at general genetic mechanisms underlying transitions in social organization. More broadly, our findings are consistent with recent theoretical studies suggesting that suppression of recombination plays a key role in facilitating coordinated shifts in coadapted traits. PMID:25455032

Purcell, Jessica; Brelsford, Alan; Wurm, Yannick; Perrin, Nicolas; Chapuisat, Michel

2014-11-17

427

GC-MS for characterization and identification of ant semiochemicals.  

PubMed

Living in a predominantly dark environment, ants rely mostly on chemical signals for communication. Trail and alarm pheromones are the most widely studied and best characterized of all ant semiochemicals, but other such compounds can influence a variety of other behaviors, including reproductive activities, sexual development, nest mate and caste recognition, and defense. A typical worker body contains more than 10 different semiochemical-producing glands, and the surface of the cuticle is covered with lipids that serve as recognition signals. The methods of choice for collection and identification of ant semiochemicals should be determined based on results of behavioral analyses. These can indicate the source (e.g., glandular, cuticular) and the nature (volatile vs. nonvolatile) of the chemical. This protocol presents a number of different methods for collecting lipid semiochemicals. These can be followed by gas chromatography (GC) coupled with mass spectrometry (MS) to better characterize, and possibly identify, the semiochemical in question. PMID:20147214

Eliyahu, Dorit

2009-07-01

428

Characterization of actinobacteria associated with three ant-plant mutualisms.  

PubMed

Ant-plant mutualisms are conspicuous and ecologically important components of tropical ecosystems that remain largely unexplored in terms of insect-associated microbial communities. Recent work has revealed that ants in some ant-plant systems cultivate fungi (Chaetothyriales) within their domatia, which are fed to larvae. Using Pseudomyrmex penetrator/Tachigali sp. from French Guiana and Petalomyrmex phylax/Leonardoxa africana and Crematogaster margaritae/Keetia hispida, both from Cameroon, as models, we tested the hypothesis that ant-plant-fungus mutualisms co-occur with culturable Actinobacteria. Using selective media, we isolated 861 putative Actinobacteria from the three systems. All C. margaritae/K. hispida samples had culturable Actinobacteria with a mean of 10.0 colony forming units (CFUs) per sample, while 26 % of P. penetrator/Tachigali samples (mean CFUs 1.3) and 67 % of P. phylax/L. africana samples (mean CFUs 3.6) yielded Actinobacteria. The largest number of CFUs was obtained from P. penetrator workers, P. phylax alates, and C. margaritae pupae. 16S rRNA gene sequencing and phylogenetic analysis revealed the presence of four main clades of Streptomyces and one clade of Nocardioides within these three ant-plant mutualisms. Streptomyces with antifungal properties were isolated from all three systems, suggesting that they could serve as protective symbionts, as found in other insects. In addition, a number of isolates from a clade of Streptomyces associated with P. phylax/L. africana and C. margaritae/K. hispida were capable of degrading cellulose, suggesting that Streptomyces in these systems may serve a nutritional role. Repeated isolation of particular clades of Actinobacteria from two geographically distant locations supports these isolates as residents in ant-plant-fungi niches. PMID:25096989

Hanshew, Alissa S; McDonald, Bradon R; Díaz Díaz, Carol; Djiéto-Lordon, Champlain; Blatrix, Rumsaïs; Currie, Cameron R

2015-01-01

429

Landmarks and ant search strategies after interrupted tandem runs.  

PubMed

During a tandem run, a single leading ant recruits a single follower to an important resource such as a new nest. To examine this process, we used a motorized gantry, which has not previously been used in ant studies, to track tandem running ants accurately in a large arena and we compared their performance in the presence of different types of landmark. We interrupted tandem runs by taking away the leader and moved a large distant landmark behind the new nest just at the time of this separation. Our aim was to determine what information followers might have obtained from the incomplete tandem run they had followed, and how they behaved after the tandem run had been interrupted. Our results show that former followers search by using composite random strategies with elements of sub-diffusive and diffusive movements. Furthermore, when we provided more landmarks former followers searched for longer. However, when all landmarks were removed completely from the arena, the ants' search duration lasted up to four times longer. Hence, their search strategy changes in the presence or absence of landmarks. Even after extensive search of this kind, former followers headed back to their old nest but did not return along the path of the tandem run they had followed. The combination of the position to which the large distant landmark behind the new nest was moved and the presence or absence of additional landmarks influenced the orientation of the former followers' paths back to the old nest. We also found that these ants exhibit behavioural lateralization in which they possibly use their right eye more than their left eye to recognize landmarks for navigation. Our results suggest that former follower ants learn landmarks during tandem running and use this information to make strategic decisions. PMID:24198259

Basari, Norasmah; Bruendl, Aisha C; Hemingway, Charlotte E; Roberts, Nicholas W; Sendova-Franks, Ana B; Franks, Nigel R

2014-03-15

430

Strategic Tool Use: Windows, Dinos and Ants  

NSDL National Science Digital Library

This professional development video clip of students engaged in Common Core Practice Standard #5- Use appropriate tools strategically. In this video clip first-graders solve a real-world measurement problem by finding the distance from their third floor classroom window to the playground below using standard and non-standard measuring tools. Additional resources include a video transcript, teaching tips, and a link to a professional development reflection activity based upon the video.

Boston, Wghb

2013-01-01

431

Regulation of antimycin biosynthesis by the orphan ECF RNA polymerase sigma factor ?AntA  

PubMed Central

Antimycins are an extended family of depsipeptides that are made by filamentous actinomycete bacteria and were first isolated more than 60 years ago. Recently, antimycins have attracted renewed interest because of their activities against the anti-apoptotic machineries inside human cells which could make them promising anti-cancer compounds. The biosynthetic pathway for antimycins was recently characterised but very little is known about the organisation and regulation of the antimycin (ant) gene cluster. Here we report that the ant gene cluster in Streptomyces albus is organized into four transcriptional units; the antBA, antCDE, antGF and antHIJKLMNO operons. Unusually for secondary metabolite clusters, the antG and antH promoters are regulated by an extracytoplasmic function (ECF) RNA polymerase sigma factor named ?AntA which represents a new sub-family of ECF ? factors that is only found in antimycin producing strains. We show that ?AntA controls production of the unusual precursor 3-aminosalicylate which is absolutely required for the production of antimycins. ?AntA is highly conserved in antimycin producing strains and the ?10 and ?35 elements at the ?AntA regulated antG and antH promoters are also highly conserved suggesting a common mechanism of regulation. We also demonstrate that altering the C-terminal Ala-Ala residues found in all ?AntA proteins to Asp-Asp increases expression of the antFG and antGHIJKLMNO operons and we speculate that this Ala-Ala motif may be a signal for the protease ClpXP. PMID:24688837

Patrick, Elaine

2014-01-01

432

Multiple Ant Species Tending Lac Insect Kerria yunnanensis (Hemiptera: Kerriidae) Provide Asymmetric Protection against Parasitoids  

PubMed Central

This study investigated the effects of ant attendance on the parasitoid community and parasitism of lac insect Kerria yunnanensis aggregations in Yunnan province, China. We manipulated ant attendance to establish three treatments: (1) ant exclusion; (2) low ant attendance by several ant species; and (3) high ant attendance by Crematogaster macaoensis. Five parasitoid species were collected, with two species contributing 82.7 and 13.2% of total abundance respectively. Total parasitoid abundance was lowest in the February sample when K. yunnanensis was in its younger life stage, being significantly lower in the ant exclusion treatment. In April, all three treatments had significantly different parasitoid abundances, being highest in the ant exclusion treatment and the lowest in the high ant attendance treatment. When ants were present, there were strong negative relationships between total parasitoid abundance and ant abundance, with the relationships being dependent upon the ant species composition and abundance. The patterns of total parasitoid abundance were driven by the two most abundant parasitoid species. Parasitoid species richness did not differ among treatments or between sample times, however, multivariate analysis confirmed that overall parasitoid community structure differed significantly among treatments and between sample times, with the high ant attendance treatment differing most from the other two treatments. Interestingly the absence of ants did not result in increased parasitism from four of the five parasitoids. Ants in lac insect farming systems have a clear role for agricultural pest management. A full understanding of the asymmetric abilities of ants to influence parasitoid communities, and affect parasitism of hosts will require further experimental manipulation to assess the relative roles of 1) the abundance of each individual ant species on parasitoid access to hosts, 2) competition among parasitoids, and 3) the interaction between the first two factors. PMID:24887398

Li, Qiao; Hoffmann, Benjamin D.; Zhang, Wei

2014-01-01

433

Plant genotype shapes ant-aphid interactions: implications for community structure and indirect plant defense.  

PubMed

Little is known about the mechanisms by which plant genotype shapes arthropod community structure. In a field experiment, we measured the effects of milkweed (Asclepias syriaca) genotype and ants on milkweed arthropods. Populations of the ant-tended aphid Aphis asclepiadis and the untended aphid Myzocallis asclepiadis varied eight- to 18-fold among milkweed genotypes, depending on aphid species and whether ants were present. There was no milkweed effect on predatory arthropods. Ants increased Aphis abundance 59%, decreased Myzocallis abundance 52%, and decreased predator abundance 56%. Milkweed genotype indirectly influenced ants via direct effects on Aphis and Myzocallis abundance. Milkweed genotype also modified ant-aphid interactions, influencing the number of ants attracted per Aphis and Myzocallis. While ant effects on Myzocallis were consistently negative, effects on Aphis ranged from antagonistic to mutualistic among milkweed genotypes. As a consequence of milkweed effects on ant-aphid interactions, ant abundance varied 13-fold among milkweed genotypes, and monarch caterpillar survival was negatively correlated with genetic variation in ant abundance. We speculate that heritable variation in milkweed phloem sap drives these effects on aphids, ants, and caterpillars. In summary, milkweed exerts genetic control over the interactions between aphids and an ant that provides defense against foliage-feeding caterpillars. PMID:18419551

Mooney, Kailen A; Agrawal, Anurag A

2008-06-01

434

Researcharticle Evolution at Two Levels in Fire Ants: The Relationship between  

E-print Network

Researcharticle Evolution at Two Levels in Fire Ants: The Relationship between Patterns of Gene the relationship between protein coding sequence evolution and gene expression patterns in the fire ants Solenopsis

Yi, Soojin

435

Yellow jackets may be an underestimated component of an ant-seed mutualism  

USGS Publications Warehouse

Yellow jackets (Hymenoptera: Vespidae) are attracted to the typically ant-dispersed seeds of trilliums and will take seeds from ants in the genus Aphaenogaster. To determine if yellow jacket, Vespula maculifrons (Buysson), presence interferes with seed foraging by ants, we presented seeds of Trillium discolor Wray to three species (A. texana carolinensis Wheeler, Formica schaufussi Mayr, and Solenopsis invicta Buren) of seed-carrying ants in areas where vespids were present or excluded. We found that interspecific aggression between yellow jackets and ants is species specific. Vespid presence decreased average foraging time and increased foraging efficiency of two of the three ant species studied, a situation that might reflect competition for a limited food source. We also found that yellow jackets removed more seeds than ants, suggestive that vespids are important, albeit underestimated, components of ant-seed mutualisms.

Bale, M.T.; Zettler, J.A.; Robinson, B.A.; Spira, T.P.; Allen, C.R.

2003-01-01

436

Renewed diversification is associated with new ecological opportunity in the Neotropical turtle ants  

E-print Network

Renewed diversification is associated with new ecological opportunity in the Neotropical turtle Keywords: biogeography; Cephalotes; Chacoan; community phylogenetics; phylogeny; radiation; speciation examine lineage diversification in the turtle ants (Cephalotes), a species-rich group of ants that has

Pierce, Naomi E.

437

Ant association facilitates the evolution of diet breadth in a lycaenid butterfly  

E-print Network

Ant association facilitates the evolution of diet breadth in a lycaenid butterfly Matthew L thoroughly examined. Lycaenid butterflies provide excellent systems for exploring mutualistic interactions by ants might facilitate host-range evolution. Specifically, experiments with the butterfly Lycaeides

Papaj, Daniel

438

Convergent evolution: the genetics of queen number in ants.  

PubMed

Large, non-recombining genomic regions underlie the polymorphism in colony queen number in two distantly related ant species. This illustrates that convergence in complex phenotypes can arise via convergence in general genomic architecture, rather than convergent changes in specific genes. PMID:25458216

Libbrecht, Romain; Kronauer, Daniel J C

2014-11-17

439

Bilingualism Aids Conflict Resolution: Evidence from the ANT Task  

ERIC Educational Resources Information Center

The need of bilinguals to continuously control two languages during speech production may exert general effects on their attentional networks. To explore this issue we compared the performance of bilinguals and monolinguals in the attentional network task (ANT) developed by Fan et al. [Fan, J., McCandliss, B.D. Sommer, T., Raz, A., Posner, M.I.…

Costa, Albert; Hernandez, Mirea; Sebastian-Galles, Nuria

2008-01-01

440

The number of queens: An important trait in ant evolution  

Microsoft Academic Search

The pervasive social and ecological differences between ant colonies that have a single queen and those that have multiple queens are defined. The evolutionary tendencies which lead to polygyny and the adaptive significance of multiple queens are examined. The discussion of the ecological consequences of polygyny and monogyny leads to a deeper understanding of territoriality, spacing and species packing in

Bert Hölldobler; Edward O. Wilson

1977-01-01

441

Elephants, giraffes and the ants in their plants  

NSDL National Science Digital Library

Nobody wants to see the elephants, giraffes and other grazing animals disappear from the eastern African savanna, but it's not just people who would miss them. Researchers have discovered that many of the ants and trees that share the mammals' turf would suffer, too.

American Association for the Advancement of Science (AAAS;)

2008-01-10

442

Worker termite Winged termite Winged Ant Termites in Wisconsin  

E-print Network

Worker termite Winged termite Winged Ant Termites in Wisconsin Insect Diagnostic Lab Note In the last five years there has been a dramatic increase in the number of sites that have active termite, Columbia, Brown, Trempealeau, Juneau and Winnebago counties. Termites have been moving northward since

Balser, Teri C.

443

Stabilities of ant nests and their adjacent soils  

NASA Astrophysics Data System (ADS)

Nests habour ants and termites and protect them from harsh environmental conditions. The structural stabilities of nests were studied to ascertain their relative vulnerability to environmental stresses. Arboreal-ant nests were pried from different trees, while epigeous-termite nests were excavated from soil surface within the sample area. Soils without any visible sign of ant or termite activity were also sampled 6 m away from the nests as control. Laboratory analysis result showed that irrespective of the tree hosts, the aggregate stabilities of the ant nests were lower than those of the ground termite, with nests formed on Cola nitida significantly showing lower aggregate stability (19.7%) than other antnest structures. Clay dispersion ratio, moisture content, water stable aggregate class <0.25mm and sand mass were each negatively correlated with aggregate stability, while water stable aggregate class1.00-0.50 mm gave a positive correlation. Nest structures were dominated more by water stable aggregate class >2.00 mm but path analysis demonstrated that water stable aggregate class <0.25 mm contributed most to the higher aggregate stability of the termite nest than the other nest. Nest aggregates had greater structural stability compared to the control soil. The higher structural stability of termite nests over other nest and soil was considered a better adaptive mechanism against body desiccation.

Echezona, B. C.; Igwe, C. A.

2012-10-01

444

Mapping the navigational knowledge of individually foraging ants, Myrmecia croslandi  

PubMed Central

Ants are efficient navigators, guided by path integration and visual landmarks. Path integration is the primary strategy in landmark-poor habitats, but landmarks are readily used when available. The landmark panorama provides reliable information about heading direction, routes and specific location. Visual memories for guidance are often acquired along routes or near to significant places. Over what area can such locally acquired memories provide information for reaching a place? This question is unusually approachable in the solitary foraging Australian jack jumper ant, since individual foragers typically travel to one or two nest-specific foraging trees. We find that within 10 m from the nest, ants both with and without home vector information available from path integration return directly to the nest from all compass directions, after briefly scanning the panorama. By reconstructing panoramic views within the successful homing range, we show that in the open woodland habitat of these ants, snapshot memories acquired close to the nest provide sufficient navigational information to determine nest-directed heading direction over a surprisingly large area, including areas that animals may have not visited previously. PMID:23804615

Narendra, Ajay; Gourmaud, Sarah; Zeil, Jochen

2013-01-01

445

Ant-like task allocation and recruitment in cooperative robots  

Microsoft Academic Search

One of the greatest challenges in robotics is to create machines that are able to interact with unpredictable environments in real time. A possible solution may be to use swarms of robots behaving in a self-organized manner, similar to workers in an ant colony. Efficient mechanisms of division of labour, in particular series-parallel operation and transfer of information among group

Michael J. B. Krieger; Jean-Bernard Billeter; Laurent Keller

2000-01-01

446

Mitochondrial genome evolution in fire ants (Hymenoptera: Formicidae)  

Microsoft Academic Search

BACKGROUND: Complete mitochondrial genome sequences have become important tools for the study of genome architecture, phylogeny, and molecular evolution. Despite the rapid increase in available mitogenomes, the taxonomic sampling often poorly reflects phylogenetic diversity and is often also biased to represent deeper (family-level) evolutionary relationships. RESULTS: We present the first fully sequenced ant (Hymenoptera: Formicidae) mitochondrial genomes. We sampled four

Dietrich Gotzek; Jessica Clarke; DeWayne Shoemaker

2010-01-01

447

Sex ratio and Wolbachia infection in the ant Formica exsecta  

E-print Network

Sex ratio and Wolbachia infection in the ant Formica exsecta LAURENT KELLER* , CATHY LIAUTARD , MAX, Division of Population Biology, PO Box 17, FIN-00014 Helsinki, Finland Sex allocation data in social Hymenoptera provide some of the best tests of kin selection, parent± ospring con¯ict and sex ratio theories

Alvarez, Nadir

448

Optimization, conflict, and nonoverlapping foraging ranges in ants.  

PubMed

An organism's foraging range depends on the behavior of neighbors, the dynamics of resources, and the availability of information. We use a well-studied population of the red harvester ant Pogonomyrmex barbatus to develop and independently parameterize models that include these three factors. The models solve for an allocation of foraging ants in the area around the nest in response to other colonies. We compare formulations that optimize at the colony or individual level and those that do or do not include costs of conflict. Model predictions were compared with data collected on ant time budgets and ant density. The strategy that optimizes at the colony level but neglects costs of conflict predicts unrealistic levels of overlap. In contrast, the strategy that optimizes at the individual level predicts realistic foraging ranges with or without inclusion of conflict costs. Both the individual model and the colony model that includes conflict costs show good quantitative agreement with data. Thus, an optimal foraging response to a combination of exploitation and interference competition can largely explain how individual foraging behavior creates the foraging range of a colony. Deviations between model predictions and data indicate that colonies might allocate a larger than optimal number of foragers to areas near boundaries between foraging ranges. PMID:14618533

Adler, Frederick R; Gordon, Deborah M

2003-11-01

449

Reproductive phenologies in a diverse temperate ant fauna  

USGS Publications Warehouse

1. Ant nuptial flights are central to understanding ant life history and ecology but have been little studied. This study examined the timing of nuptial flights, the synchronicity of nuptial flights (as a potential index of mating strategy), and variation in nuptial flights with elevation and among years in a diverse temperate ant fauna. 2. Flights occurred throughout the year, but were concentrated in the beginning of summer and in early fall (autumn). Relative to the entire flight season, closely related species tended to be more likely than expected by chance to fly at similar times, perhaps because of phylogenetic constraints on life history evolution. 3. Flights were relatively synchronous within species for nearly all species considered, but synchronicity did not appear to be a robust estimate of overall mating strategy. 4. Overall patterns in nuptial flights among species and the timing of flights for individual species varied with elevation, but did not vary greatly among years. 5. Although this study is one of the most comprehensive on the reproductive flight phenologies of ants, much remains to be learned about the causes and consequences of such spatial and temporal variation in flight phenology. ?? 2007 The Royal Entomological Society.

Dunn, R.R.; Parker, C.R.; Geraghty, M.; Sanders, N.J.

2007-01-01

450

In search of ant ancestors Ted R. Schultz*  

E-print Network

of earthworms in this role. They are among the leading predators of inver- tebrates in most ecosystems of biological disciplines, it is especially important that we understand the unique evolutionary history- atics and, indeed, for ant biology in general by Ho¨lldobler and Wilson (4) (exhaustive biological

Schultz, Ted

451

Host specificity among Maculinea butterflies in Myrmica ant nests  

Microsoft Academic Search

Ecological studies have been made of all 5 European species of Maculinea. These confirm that M. nausithous and M. rebeli live underground in Myrmica ant nests for 10 months of the year, as has long been known for the other 3 species. The main discovery was that each Maculinea species depends on a single, and different, host species of Myrmica.

J. A. Thomas; G. W. Elmes; J. C. Wardlaw; M. Woyciechowski

1989-01-01

452

Heavy metal pollution disturbs immune response in wild ant populations  

Microsoft Academic Search

Concern about the effects of environmental contaminants on immune function in both humans and wildlife is growing and practically nothing is known about this impact on terrestrial invertebrates, even though they are known to easily accumulate pollutants. We studied the effect of industrial heavy metal contamination on immune defense of a free-living wood ant (Formica aquilonia). To find out whether

Jouni Sorvari; Liisa M. Rantala; Markus J. Rantala; Harri Hakkarainen; Tapio Eeva

2007-01-01

453

SHORT COMMUNICATION Attraction of ants by an invasive Acacia  

E-print Network

SHORT COMMUNICATION Attraction of ants by an invasive Acacia MARKUS P. EICHHORN, LOUISE C. RATLIFFE be deprived of their co-evolved mutualists. In southern Portugal Acacia dealbata has become naturalised induction, extra-floral nectaries, invasive species, Linepithema humile, Portugal. Introduction Acacia trees

Nottingham, University of

454

Evolutionary patterns of proteinase activity in attine ant fungus gardens  

Microsoft Academic Search

BACKGROUND: Attine ants live in symbiosis with a basidiomycetous fungus that they rear on a substrate of plant material. This indirect herbivory implies that the symbiosis is likely to be nitrogen deprived, so that specific mechanisms may have evolved to enhance protein availability. We therefore hypothesized that fungal proteinase activity may have been under selection for efficiency and that different

Tatyana A Semenova; David P Hughes; Jacobus J Boomsma; Morten Schiøtt

2011-01-01

455

AUTOMATED RADIO NETWORK DESIGN USING ANT COLONY OPTIMIZATION  

E-print Network

AUTOMATED RADIO NETWORK DESIGN USING ANT COLONY OPTIMIZATION by Jeffrey Allen Sharkey A thesis by each member of the thesis committee and has been found to be satisfactory regarding content, English help as I learned about radio systems and propagation algorithms. I would like to thank Dr. John Paxton

Dyer, Bill

456

VideoANT: Extending Online Video Annotation beyond Content Delivery  

ERIC Educational Resources Information Center

This paper expands the boundaries of video annotation in education by outlining the need for extended interaction in online video use, identifying the challenges faced by existing video annotation tools, and introducing Video-ANT, a tool designed to create text-based annotations integrated within the time line of a video hosted online. Several…

Hosack, Bradford

2010-01-01

457

The economy of worker reproduction in Acromyrmex leafcutter ants  

Microsoft Academic Search

Workers of most eusocial Hymenoptera can produce sons but rarely do so in the presence of the queen, despite the potentially high fitness payoff of direct reproduction. It has often been suggested that col- ony-level productivity costs may outweigh the fitness advantages of worker reproduction, but this has never been shown. We estimated these costs in two ant species with

Michiel B. Dijkstra; Jacobus J. Boomsma

2007-01-01

458

Global invasion history of the Fire Ant Solenopsis invicta  

Technology Transfer Automated Retrieval System (TEKTRAN)

The fire ant Solenopsis invicta is a serious agricultural, ecological, and public health pest that was inadvertently introduced into the southern USA almost a century ago and into California and other regions of the world more recently. An assessment of genetic variation at a diverse set of molecula...

459

A BARREL of fun in AntARcticA  

E-print Network

A BARREL of fun in AntARcticA National Aeronautics and Space Administration www.nasa.gov Volume 10 their own remote balloon field campaigns. This is the second time BARREL has taken to the skies over over Halley station to float above Antarctica and observe magnetic fields. Balloon Array for Radiation

Christian, Eric

460

The genome of the fire ant Solenopsis invicta  

PubMed Central

Ants have evolved very complex societies and are key ecosystem members. Some ants, such as the fire ant Solenopsis invicta, are also major pests. Here, we present a draft genome of S. invicta, assembled from Roche 454 and Illumina sequencing reads obtained from a focal haploid male and his brothers. We used comparative genomic methods to obtain insight into the unique features of the S. invicta genome. For example, we found that this genome harbors four adjacent copies of vitellogenin. A phylogenetic analysis revealed that an ancestral vitellogenin gene first underwent a duplication that was followed by possibly independent duplications of each of the daughter vitellogenins. The vitellogenin genes have undergone subfunctionalization with queen- and worker-specific expression, possibly reflecting differential selection acting on the queen and worker castes. Additionally, we identified more than 400 putative olfactory receptors of which at least 297 are intact. This represents the largest repertoire reported so far in insects. S. invicta also harbors an expansion of a specific family of lipid-processing genes, two putative orthologs to the transformer/feminizer sex differentiation gene, a functional DNA methylation system, and a single putative telomerase ortholog. EST data indicate that this S. invicta telomerase ortholog has at least four spliceforms that differ in their use of two sets of mutually exclusive exons. Some of these and other unique aspects of the fire ant genome are likely linked to the complex social behavior of this species. PMID:21282665

Wurm, Yannick; Wang, John; Riba-Grognuz, Oksana; Corona, Miguel; Nygaard, Sanne; Hunt, Brendan G.; Ingram, Krista K.; Falquet, Laurent; Nipitwattanaphon, Mingkwan; Gotzek, Dietrich; Dijkstra, Michiel B.; Oettler, Jan; Comtesse, Fabien; Shih, Cheng-Jen; Wu, Wen-Jer; Yang, Chin-Cheng; Thomas, Jerome; Beaudoing, Emmanuel; Pradervand, Sylvain; Flegel, Volker; Cook, Erin D.; Fabbretti, Roberto; Stockinger, Heinz; Long, Li; Farmerie, William G.; Oakey, Jane; Boomsma, Jacobus J.; Pamilo, Pekka; Yi, Soojin V.; Heinze, Jürgen; Goodisman, Michael A. D.; Farinelli, Laurent; Harshman, Keith; Hulo, Nicolas; Cerutti, Lorenzo; Xenarios, Ioannis; Shoemaker, DeWayne; Keller, Laurent

2011-01-01

461

Three-dimensional sampling method for characterizing ant mounds  

Technology Transfer Automated Retrieval System (TEKTRAN)

A field-portable 3D laser scanner was employed as a means of digitizing the surface of fire ant (Solenopsis invicta Buren) mounds for analysis of shape and orientation in Mississippi and Oklahoma. Estimates of above-ground mound volume obtained through manual measurements of mound length, width, an...

462

Fire ant baits and biocontrol with pathogens update  

Technology Transfer Automated Retrieval System (TEKTRAN)

The insect growth regulator (IGR) methoprene (isopropyl-(2E,4E,7R,S)-11-methoxy-3,7,11-trimethyldodeca-2,4-dienoate) has been shown to have deleterious effects on red imported fire ants, Solenopsis invicta. It interferes with normal development of worker caste brood and reduces queen egg production...

463

Thermal ecology of the neotropical army ant Eciton burchellii.  

PubMed

I explored the thermal ecology of Eciton burchellii, a New World army ant, in primary forest and forest fragments in the Atlantic lowlands of Costa Rica in 2002 and 2003. My primary objective was to determine whether high surface temperatures in pastures surrounding forest fragments posed a thermal barrier to ant colonies within those fragments; secondarily, I assessed whether thermal gradients within continuous moist forest were sufficient to elicit avoidance reactions from foraging colonies. E. burchellii colonies in forest fragments avoided entering open pasture in full sun (51.3 degrees C) on 100% of all edge interactions; however, edges were readily crossed where artificial shaded areas had previously been installed. Ant raids in primary forest avoided artificially established temperatures >43 degrees C but tolerated 45.5 degrees C in the presence of prey baits. Captive ants held at 43 degrees C survived 18.5 min; at temperatures of 51.3 degrees C survival time was only 2.8 min. Ants running on established foraging trails increased running velocity by 18% when substrate temperature was raised from 28.4 degrees to 38.0 degrees C, and they abandoned trails at temperatures >43 degrees C. The standard deviation (s) of temperatures on active raid trails in continuous forest was 2.13 degrees C, while nearby systematic sampling revealed a greater background standard deviation of 4.13 degrees C. E. burchellii colonies in this region appear to be living surprisingly near their upper limits of thermal tolerance. The heat of open pastures alone is sufficient to prevent their exiting forest fragments, or entering similarly hot areas within continuous forest. Shaded vegetative corridors are sufficient to permit mobility between isolated fragments, and their preservation should be encouraged. Despite views that tropical lowland moist forests have an essentially homogenous microclimate, army ants appear to avoid local hot spots on the forest floor, steering daily foraging trails to follow cooler routes than would be expected by chance. As deforestation remakes tropical landscapes worldwide, it is important to consider the thermal consequences of these actions and their effect on keystone organisms such as army ants. Changes in global climate patterns are likely to affect even evergreen tropical systems whose organisms may be sensitive to finer microclimatic variation than previously suspected. PMID:16826991

Meisel, Joe E

2006-06-01

464

An improved ant colony optimization approach for optimization of process planning.  

PubMed

Computer-aided process planning (CAPP) is an important interface between computer-aided design (CAD) and computer-aided manufacturing (CAM) in computer-integrated manufacturing environments (CIMs). In this paper, process planning problem is described based on a weighted graph, and an ant colony optimization (ACO) approach is improved to deal with it effectively. The weighted graph consists of nodes, directed arcs, and undirected arcs, which denote operations, precedence constraints among operation, and the possible visited path among operations, respectively. Ant colony goes through the necessary nodes on the graph to achieve the optimal solution with the objective of minimizing total production costs (TPCs). A pheromone updating strategy proposed in this paper is incorporated in the standard ACO, which includes Global Update Rule and Local Update Rule. A simple method by controlling the repeated number of the same process plans is designed to avoid the local convergence. A case has been carried out to study the influence of various parameters of ACO on the system performance. Extensive comparative experiments have been carried out to validate the feasibility and efficiency of the proposed approach. PMID:25097874

Wang, JinFeng; Fan, XiaoLiang; Ding, Haimin

2014-01-01

465

Tooth hardness increases with zinc-content in mandibles of young adult leaf-cutter ants.  

PubMed

A wide variety of arthropods and members of other phyla have elevated concentrations of Zn, Mn, other heavy metals and halogens in their jaws, leg claws, and other "tools" for interacting with the environment. While measured Zn concentrations reach 25% of dry mass in scorpion stings, concentrations are often lower than this and the enriched structures are not heavily biomineralized like vertebrate teeth and the radula of mollusks. For this reason, the degree to which the inorganic components of these structures modify their mechanical properties is in question. Here we address this problem by measuring hardness during the development of Zn accumulations in ant mandibles. We found that Zn is incorporated into the mandibular teeth of leaf-cutter ants during early adult life, reaching concentrations of about 16% of dry mass. We show that the hardness of the mandibular teeth increases nearly three-fold as the adults age and that hardness correlates with Zn content ( r=0.91). We suggest that young adults rarely cut leaves partly because their mandibles are not yet rich in Zn. Zinc enrichment (along with enrichment by other heavy metals and halogens) may play an unrecognized role in the behavioral ecology and evolution of a wide variety of invertebrates. PMID:12536282

Schofield, Robert M S; Nesson, Michael H; Richardson, Kathleen A

2002-12-01

466

Complex host-pathogen coevolution in the Apterostigma fungus-growing ant-microbe symbiosis  

Microsoft Academic Search

BACKGROUND: The fungus-growing ant-microbe symbiosis consists of coevolving microbial mutualists and pathogens. The diverse fungal lineages that these ants cultivate are attacked by parasitic microfungi of the genus Escovopsis. Previous molecular analyses have demonstrated strong phylogenetic congruence between the ants, the ants-cultivated fungi and the garden pathogen Escovopsis at ancient phylogenetic levels, suggesting coevolution of these symbionts. However, few studies

Nicole M Gerardo; Ulrich G Mueller; Cameron R Currie

2006-01-01

467

Ants on swollen-thorn acacias: species coexistence in a simple system  

Microsoft Academic Search

On the black cotton soils of the Laikipia ecosystem in Kenya, two swollen-thorn acacia species support nine ant species,\\u000a four of which are apparently obligate plant-ants. Among the ants, there are five species of Crematogaster, two species of Camponotus, and one each of Tetraponera and Lepisota. Acacia drepanolobium is host to four ant species that are both common and mutually

T. P. Young; Cynthia H. Stubblefield; Lynne A. Isbell

1996-01-01

468

Microbial Community Structure of Leaf-Cutter Ant Fungus Gardens and Refuse Dumps  

Microsoft Academic Search

BackgroundLeaf-cutter ants use fresh plant material to grow a mutualistic fungus that serves as the ants' primary food source. Within fungus gardens, various plant compounds are metabolized and transformed into nutrients suitable for ant consumption. This symbiotic association produces a large amount of refuse consisting primarily of partly degraded plant material. A leaf-cutter ant colony is thus divided into two

Jarrod J. Scott; Kevin J. Budsberg; Garret Suen; Devin L. Wixon; Teri C. Balser; Cameron R. Currie

2010-01-01

469

Nutritional Benefits of Crematogaster mimosae Ants and Acacia drepanolobium Gum for Patas  

E-print Network

Nutritional Benefits of Crematogaster mimosae Ants and Acacia drepanolobium Gum for Patas Monkeys (Erythrocebus patas) are midsized primates that feed extensively on the gum of Acacia drepanolobium and the ants their feeding behavior on ants and gum with that of closely related, sympatric vervets (Chlorocebus pygeryth

470

Ant Colony Optimization and its Application to Boolean Satisfiability for Digital VLSI Circuits  

E-print Network

Ant Colony Optimization and its Application to Boolean Satisfiability for Digital VLSI Circuits and Computer Engineering Dept., Rutgers University Piscataway, NJ 08854, USA Abstract Ant Colony Optimization (ACO) [8] is a non- deterministic algorithm framework that mimics the forag- ing behavior of ants

Parashar, Manish

471

POPULATION GENETICS STUDY OF THE IMPORTED FIRE ANTS (FORMICIDAE: SOLENOPSIS SPP.)  

E-print Network

POPULATION GENETICS STUDY OF THE IMPORTED FIRE ANTS (FORMICIDAE: SOLENOPSIS SPP.) By Rajesh Babu Pathology Mississippi State, Mississippi August 2009 #12;POPULATION GENETICS STUDY OF THE IMPORTED FIRE ANTS. Caprio Title of Study: POPULATION GENETICS STUDY OF THE IMPORTED FIRE ANTS (FORMICIDAE: SOLENOPSIS SPP

Ray, David

472

Bahamas Naturalist & Journal of Science September 2006 27 THE ANTS OF SMALL  

E-print Network

Bahamas Naturalist & Journal of Science September 2006 27 THE ANTS OF SMALL BAHAMIAN CAYS Lloyd Morrison Missouri State University, Ohio Abstract Ants are ubiquitous in the Bahamas, and are found even on the smallest cays, Surveys for ants on over 260 small cays in four archipelagos (Exuma Cays, Great Exuma

Morrison, Lloyd W.

473

BIOTROPICA 35(2): 295300 2003 Contrasting Responses to Induction Cues by Ants Inhabiting  

E-print Network

295 BIOTROPICA 35(2): 295­300 2003 Contrasting Responses to Induction Cues by Ants Inhabiting Maieta guianensis (Melastomataceae)1 ABSTRACT The two most common ant associates of the understory-plants by ants. RESUMO As duas formigas que mais comumente se associam com a mirmeco´fita de sub-bosque Maieta

Bruna, Emilio M.

474

Ant Ecology Lori Lach, Catherine L. Parr, and Kirsti L. Abbott  

E-print Network

Ant Ecology EDITED BY Lori Lach, Catherine L. Parr, and Kirsti L. Abbott 1 #12;Contents Foreword of Abbreviations xvii Part I: Global Ant Diversity and Conservation 1 1. Taxonomy, Phylogenetics, and Evolution 3 Philip S. Ward Box 1.1 Applications of taxonomy: why should we name ants? 11 Philip S. Ward Box 1.2 How

Mooney, Kailen A.

475

Individual Rules for Trail Pattern Formation in Argentine Ants (Linepithema humile)  

E-print Network

Individual Rules for Trail Pattern Formation in Argentine Ants (Linepithema humile) Andrea Perna1 by Argentine ants exploring an empty arena. Using a novel imaging and analysis technique we estimated pheromone the response function of individual ants to pheromone concentrations by looking at correlations between

Theraulaz, Guy

476

Evaluating alternative hypotheses for the early evolution and diversification of ants  

E-print Network

Evaluating alternative hypotheses for the early evolution and diversification of ants Sea´n G (received for review July 12, 2006) Ants are the world's most diverse and ecologically dominant eusocial organisms. Resolving the phylogeny and timescale for major ant lineages is vital to understanding how

Schultz, Ted

477

Arboreal Ants Use the ``VelcroH Principle'' to Capture Very Large Prey  

E-print Network

Arboreal Ants Use the ``VelcroH Principle'' to Capture Very Large Prey Alain Dejean1 *, Ce Biologi´a Animal, Facultad de Ciencias, Universidad de Granada, Granada, Spain Abstract Plant-ants live and sometimes with extra-floral nectar (EFN) and/or food bodies (FBs); the ants can also attend sap

Paris-Sud XI, Université de

478

Comparing Adaptivity of Ants using NEAT and Teo Gelles & Mario Sanchez  

E-print Network

Comparing Adaptivity of Ants using NEAT and rtNEAT Teo Gelles & Mario Sanchez Swarthmore College Class of 2016 Abstract Although individual ants have an extremely basic intelligence, and are completely incapable of surviving on their own, colonies of ants can develop remarkably sophisticated and biologically

Meeden, Lisa A.

479

Ecological consequences of interactions between ants and honeydew-producing insects  

E-print Network

Review Ecological consequences of interactions between ants and honeydew-producing insects John D 36849, USA Interactions between ants and honeydew-producing hemipteran insects are abundant and widespread in arthropod food webs, yet their ecological consequences are very poorly known. Ant

Behmer, Spencer T.

480

Research article Protein marking reveals predation on termites by the woodland ant,  

E-print Network

Research article Protein marking reveals predation on termites by the woodland ant, Aphaenogaster; accepted 26 March 2007. Published Online First 20 April 2007 Abstract. Subterranean termites provide a major poten- tial food source for forest-dwelling ants, yet the inter- actions between ants and termites

Buczkowski, Grzegorz

481

An improved feature selection method based on ant colony optimization (ACO) evaluated on face recognition system  

Microsoft Academic Search

Feature selection (FS) is a most important step which can affect the performance of a pattern recognition system. This paper proposes a novel feature selection method based on ant colony optimization (ACO). ACO algorithm is inspired of ant’s social behavior in their search for the shortest paths to food sources. Most common techniques for ACO-based feature selection use the priori

Hamidreza Rashidy Kanan; Karim Faez

2008-01-01

482

Do Desert Ants Use Partial Image Matching for Landmark Navigation? \\Lambda  

E-print Network

Do Desert Ants Use Partial Image Matching for Landmark Navigation? \\Lambda Ralf M¨oller 1 of Zoology University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland Desert ants (genus in desert ants, Cataglyphis bicolor (Hymenoptera: Formici­ dae). Experientia, 35:1569--1571, 1979. \\Lambda

Moeller, Ralf

483

ANTS AS BIOLOGICAL INDICATORS FOR MONITORING CHANGES IN ARID ENVIRONMENTS: LESSONS FOR MONITORING PROTECTED AREAS  

EPA Science Inventory

The responses of ant communities to structural change (removal of an invasive were studied in a replicated experiment in a Chihuahuan Desert grassland. The results from sampling of ant communities by pit-fall trapping were validated by mapping ant colonies on the experimental plo...

484

ANTS AS BIOLOGICAL INDICATORS FOR MONITORING CHANGES IN ARID ENVIRONMENTS: LESSONS FOR MONITORING PROTECTED AREAS  

EPA Science Inventory

The responses of ant communities to structural change (removal of an invasive were studied in a replicated experiment in a Chihuahuan Desert grassland. The results from sampling of ant communities by pit-fall trapping were validated by mapping ant colonies on the expe...

485

COMPARISON OF ANOVA AND KRIGING IN DETECTING ANT RESPONSES TO ENVIRONMENTAL STRESSORS  

EPA Science Inventory

In an ecosystems, ants effect ecosystem functions such as water infiltration, soil nutrient distribution and composition of the soil seed bank. Ants have also been used as indicators of ecosystems health. In a study, we hypothesized that some ant species would respond to changes ...

486

Are flower-visiting ants mutualists or antagonists? A study in a gynodioecious wild strawberry  

Microsoft Academic Search

Ants are common flower visitors, but their effects on plant reproductive fitness have not often been assessed. Flower-visiting ants were studied to determine whether they are antagonists or mutualists and whether they could influence floral or breeding system evolution in gynodioecious wild strawberry (Fragaria virginiana). Ant and flying pollinator (bees\\/flies) access to plants was manip- ulated, and visitation, fruit, and

TIA-LYNN ASHMAN; EMILEY A. KING

2005-01-01

487

Rainfall facilitates the spread, and time alters the impact, of the invasive Argentine ant.  

PubMed

Climate change may exacerbate invasions by making conditions more favorable to introduced species relative to native species. Here we used data obtained during a long-term biannual survey of the distribution of ant species in a 481-ha preserve in northern California to assess the influence of interannual variation in rainfall on the spread of invasive Argentine ants, Linepithema humile, and the displacement of native ant species. Since the survey began in 1993, Argentine ants have expanded their range into 74 new hectares. Many invaded hectares were later abandoned, so the range of Argentine ants increased in some years and decreased in others. Rainfall predicted both range expansion and interannual changes in the distribution of Argentine ants: high rainfall, particularly in summer months, promoted their spread in the summer. This suggests that an increase in rainfall will promote a wider distribution of Argentine ants and increase their spread into new areas in California. Surprisingly, the distribution of two native ant species also increased following high rainfall, but only in areas of the preserve that were invaded by L. humile. Rainfall did not have a negative impact on total native ant species richness in invaded areas. Instead, native ant species richness in invaded areas increased significantly over the 13 years of observation. This suggests that the impact of Argentine ants on naïve ant communities may be most severe early in the invasion process. PMID:18004595

Heller, Nicole E; Sanders, Nathan J; Shors, Jessica Wade; Gordon, Deborah M

2008-03-01

488

Cooperation, conflict, and coevolution in the attine ant-fungus symbiosis  

Microsoft Academic Search

Fungus-growing ants in the tribe Attini represent a classic example of a mutualism. These ants obligately depend on fungus as their major food source, while the fungus receives both vegetative substrate (nourishment) from the ants and protection from pathogens. Here, we try to identify both benefits and costs of the association by using cultivar switch experiments. We assessed the benefits

Natasha J. Mehdiabadi; Benjamin Hughes; Ulrich G. Mueller

2005-01-01

489

Single class of queen pheromones stops worker reproduction in ants, bees and wasps  

E-print Network

Single class of queen pheromones stops worker reproduction in ants, bees and wasps A new study pheromones in wasps, ants and some bees is strikingly similar, even though these insects are separated in representative species of wasps, bees, and ants. After identifying candidate queen pheromones by analysing

Wenseleers, Tom

490

Study: Honeybees make ruthless relatives Many species of ants, wasps and bees conduct in cannibalism  

E-print Network

Study: Honeybees make ruthless relatives Many species of ants, wasps and bees conduct. The same applies to wasps and ants. But many don't survive. In all of these cannibalistic acts, each eater to a new survey of more than 100 species of ants, bees and wasps conducted by Wenseleers and Francis

Wenseleers, Tom

491

Codebook design by a hybridization of ant colony with improved LBG algorithm  

Microsoft Academic Search

Ant colony algorithm is a newly emerged stochastic searching optimization algorithm in recent years. In this paper, an appropriately adapted ant colony system embedded with a simple improved LBG algorithm is proposed for vector quantization codebook design. The emphasis is put on the design of the probability transfer function and the tabu list in the ant colony algorithm, the utilization

Li Xia; Luo Xuehui; Zhang Jihong

2003-01-01

492

Ant semiochemicals limit apterous aphid dispersal Thomas H. Oliver1,*, Alla Mashanova2  

E-print Network

Ant semiochemicals limit apterous aphid dispersal Thomas H. Oliver1,*, Alla Mashanova2 , Simon R in order to obtain benefit. Ants are known to limit alate aphid dispersal by physically removing wings dispersal and higher local densities of aphids, which benefit ants in terms of increased honeydew and prey

493

Aphid-tending Ants Affect Secondary Users in Leaf Shelters and Rates of Herbivory on  

E-print Network

Aphid-tending Ants Affect Secondary Users in Leaf Shelters and Rates of Herbivory on Salix. We studied the effects of a keystone species, the aphid-tending ant (Formica obscuripes California. Leaf shelters on branches with aphid-tending ants had 54% more individuals than shelters

Sanders, Nathan J.

494

Lasius niger ants discriminate aphids based on their cuticular hydrocarbons Corsin Langa,1  

E-print Network

Lasius niger ants discriminate aphids based on their cuticular hydrocarbons Corsin Langa,1 2011 Final acceptance 22 August 2011 Available online xxx MS. number: 11-00421R Keywords: ant aphid partner to recognize the other. In anteaphid mutualisms, ants have to recognize whether an aphid colony

Richner, Heinz

495

Sensitivity and feeding efficiency of the black garden ant Lasius niger to sugar resources  

E-print Network

. The feeding behavior of ants appears to be primarily regulated by the energy content of the food solution and honeydew represent the main source of energy for many ant species and contribute towards maintaining response curve and food intake efficiency of the aphid tending ant, Lasius niger for major sugars found

Boyer, Edmond

496

Interactions between granivorous and omnivorous ants in a desert grassland: results from a long-term  

E-print Network

, Forelius cf pruinosus and Dorymyr- mex insana, in a desert grassland were analysed. The food competitionInteractions between granivorous and omnivorous ants in a desert grassland: results from a long evidence that granivorous ants compete for seeds in desert ecosystems. But ants that diverge in diet may

Kaspari, Mike

497

The influence of ants on host plant selection by Jalmenus evagoras , a myrmecophilous lycaenid butterfly  

Microsoft Academic Search

(1) Females of the myrmecophilous lycaenid butterfly, Jalmenus evagoras are far more likely to lay eggs on plants that contain their attendant ants, Iridomyrmex sp. 25 than on plants without ants, although the clutch sizes of individual egg masses laid in either situation is the same. (2) Ovipositing females respond to the presence or absence of ants before they alight

Naomi E. Pierce; Mark A. Elgar

1985-01-01

498

78 FR 70530 - Notice of Determination; New and Revised Treatments for the Imported Fire Ant Program  

Federal Register 2010, 2011, 2012, 2013

...and Revised Treatments for the Imported Fire Ant Program AGENCY: Animal and Plant Health...certain treatment schedules for the Imported Fire Ant Program in the Plant Protection and...and revised treatments in the imported fire ant program. Based on the treatment...

2013-11-26

499

Of Robot Ants and Elephants Asaf Shiloni, Noa Agmon and Gal A. Kaminka  

E-print Network

Of Robot Ants and Elephants Asaf Shiloni, Noa Agmon and Gal A. Kaminka The MAVERICK Group Computer computational classes of robots emerge as focal points of recent research: Robot Ants and robot Elephants. Ants, in effect turning their work area into a shared memory. By comparison, elephants are com- putationally

Kaminka, Gal A.

500

An orb-weaver spider exploits an ant–acacia mutualism for enemy-free space  

PubMed Central

Exploiters of protection mutualisms are assumed to represent an important threat for the stability of those mutualisms, but empirical evidence for the commonness or relevance of exploiters is limited. Here, I describe results from a manipulative study showing that an orb-weaver spider, Eustala oblonga, inhabits an ant-acacia for protection from predators. This spider is unique in the orb-weaver family in that it associates closely with both a specific host plant and ants. I tested the protective effect of acacia ants on E.?oblonga by comparing spider abundance over time on acacias with ants and on acacias from which entire ant colonies were experimentally removed. Both juvenile and adult spider abundance significantly decreased over time on acacias without ants. Concomitantly, the combined abundance of potential spider predators increased over time on acacias without ants. These results suggest that ant protection of the ant-acacia Acacia melanocerus also protects the spiders, thus supporting the hypothesis that E.?oblonga exploits the ant–acacia mutualism for enemy-free space. Although E.?oblonga takes advantage of the protection services of ants, it likely exacts little to no cost and should not threaten the stability of the ant–acacia mutualism. Indeed, the potential threat of exploiter species to protection mutualisms in general may be limited to species that exploit the material rewards traded in such mutualisms rather than the protection services. PMID:24558583

Styrsky, John D

2014-01-01