Matching Items (63)
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Description
This project aims to better understand aggression in a cooperative social system, specifically within the ant species Pogonomyrmex Californicus. The queens of some populations of these ants form cooperative associations of unrelated queens during nest foundation, while others prefer to form solitary nests and may show aggression towards unwanted nest

This project aims to better understand aggression in a cooperative social system, specifically within the ant species Pogonomyrmex Californicus. The queens of some populations of these ants form cooperative associations of unrelated queens during nest foundation, while others prefer to form solitary nests and may show aggression towards unwanted nest mates. Because it is difficult to collect large amounts of data from a wild population and laboratory environments cannot capture the scale of nature, we created a computer simulation based on data collected in the lab and the field that emulates the life cycle of this species of ants. By manipulating behavioral and environmental conditions and observing the results we were able to better understand the advantages and disadvantages of showing aggression in this cooperative social system.
Created2016-05
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Description

Investigating local-scale interactions within a network makes it possible to test hypotheses about the mechanisms of global network connectivity and to ask whether there are general rules underlying network function across systems. Here we use motif analysis to determine whether the interactions within social insect colonies resemble the patterns exhibited

Investigating local-scale interactions within a network makes it possible to test hypotheses about the mechanisms of global network connectivity and to ask whether there are general rules underlying network function across systems. Here we use motif analysis to determine whether the interactions within social insect colonies resemble the patterns exhibited by other animal associations or if they exhibit characteristics of biological regulatory systems. Colonies exhibit a predominance of feed-forward interaction motifs, in contrast to the densely interconnected clique patterns that characterize human interaction and animal social networks. The regulatory motif signature supports the hypothesis that social insect colonies are shaped by selection for network patterns that integrate colony functionality at the group rather than individual level, and demonstrates the utility of this approach for analysis of selection effects on complex systems across biological levels of organization.

ContributorsWaters, James (Author) / Fewell, Jennifer (Author) / College of Liberal Arts and Sciences (Contributor)
Created2012-07-16
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Description

We asked how team dynamics can be captured in relation to function by considering games in the first round of the NBA 2010 play-offs as networks. Defining players as nodes and ball movements as links, we analyzed the network properties of degree centrality, clustering, entropy and flow centrality across teams

We asked how team dynamics can be captured in relation to function by considering games in the first round of the NBA 2010 play-offs as networks. Defining players as nodes and ball movements as links, we analyzed the network properties of degree centrality, clustering, entropy and flow centrality across teams and positions, to characterize the game from a network perspective and to determine whether we can assess differences in team offensive strategy by their network properties. The compiled network structure across teams reflected a fundamental attribute of basketball strategy. They primarily showed a centralized ball distribution pattern with the point guard in a leadership role.

However, individual play-off teams showed variation in their relative involvement of other players/positions in ball distribution, reflected quantitatively by differences in clustering and degree centrality. We also characterized two potential alternate offensive strategies by associated variation in network structure: (1) whether teams consistently moved the ball towards their shooting specialists, measured as “uphill/downhill” flux, and (2) whether they distributed the ball in a way that reduced predictability, measured as team entropy.

These network metrics quantified different aspects of team strategy, with no single metric wholly predictive of success. However, in the context of the 2010 play-offs, the values of clustering (connectedness across players) and network entropy (unpredictability of ball movement) had the most consistent association with team advancement. Our analyses demonstrate the utility of network approaches in quantifying team strategy and show that testable hypotheses can be evaluated using this approach. These analyses also highlight the richness of basketball networks as a dataset for exploring the relationships between network structure and dynamics with team organization and effectiveness.

ContributorsFewell, Jennifer (Author) / Armbruster, Dieter (Author) / Ingraham, John (Author) / Petersen, Alexander (Author) / Waters, James (Author) / College of Liberal Arts and Sciences (Contributor)
Created2012-11-06