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Synopsis Recent studies in group-living species suggest that being a valuable group member (a source of information or other resources) should increase social connectedness. This is because individuals may recognize and associate more with valuable individuals to increase the chances of benefiting from their activity, a process we refer to here as adaptive social plasticity. However, it is still unclear what minimum cognitive abilities are required for animals to alter their social interactions based on the value provided by different group members. We varied the cognitive skills of individuals in an agent-based model and evaluated changes in how access to a food resource impacts an informed agent's social connectedness. We modeled a social foraging scenario in an arena with one food patch, which only one informed individual (i.e., producer) can make accessible. Agents’ movement decisions were driven by three cognitive-based parameters: attention (probability of perceiving successful foragers), preference (probability of following successful foragers), and memory (number of time steps a successful forager was remembered). To understand what combination of these parameters may facilitate adaptive social plasticity, we compared the producer's strength (number of interactions) in a proximity network and the foraging success of non-producers between simulations with different combinations of parameter values. We found that non-zero values of each of our parameters are necessary for increases in producer strength and non-producer foraging success to occur. The largest increases in producer strength were seen at intermediate memory values and high values of attention and preference. Unless foragers were programmed to be able to move directly to the food patch when it was accessible to them, a non-zero value of memory was needed for them to experience an increase in foraging success. Furthermore, relationships between attention, memory, and foraging success were influenced by preference values, with the highest foraging success achieved at low to intermediate values of preference. Our results highlight the necessity of certain cognitive skills for animals to take advantage of the foraging success of their group mates, and scenarios in which rigid following behavior may lead to less beneficial results for foragers. This model lays the groundwork for further investigations into the cognitive and environmental factors expected to influence a feedback process between social connections and the value provided and received by group members.
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Sensory perception plays a larger role in foraging efficiency than does heavy-tailed movement strategies.
Animals must balance their rates of energetic intake and expenditure while foraging. Several mathematical models have been put forward as energetically optimal foraging strategies when the food environment is sparse (i.e., the distance between food patches in the environment is much larger than the distance from which the forager can perceive food). In particular, Lévy walks with a power law exponent approaching 1 are considered optimal for destructive foragers. However, these models have yet to explore the role of sensory perception in foraging success as the distance between food patches approaches the distance from which the forager can perceive food. Here, we used an agent-based modeling approach to address this question. Our results concur that lower values of the power law exponent (i.e. values approaching 1) result in the most food found, but in contrast to previous studies, we note that, in many cases, lower exponents are not optimal when we consider food found per unit distance traveled. For example, higher values of the exponent resulted in comparable or higher foraging success relative to lower values when the forager's range of sensory perception was restricted to an angle±30° from its current heading. In addition, we find that sensory perception has a larger effect on foraging success than the power law exponent. These results suggest that a deeper examination of how animals perceive food sources from a distance may affect longstanding assumptions regarding the optimality of Lévy walk foraging patterns, and lend support to the developing theoretical shift towards models that place increasing emphasis on how organisms interact with their environments.
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- Award ID(s):
- 1655529
- PAR ID:
- 10135146
- Date Published:
- Journal Name:
- Ecological modelling
- Volume:
- 404
- ISSN:
- 0304-3800
- Page Range / eLocation ID:
- 69-82
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/doi:10.1016/j.ecolmodel.2019.02.015
