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Sociological and urban studies have consistently reported that human behavior exhibits a discernible correlation with population size, following a power-law function. Individuals residing in larger communities exhibit significantly higher levels of activity in contrast to their counterparts in smaller communities. However, the underlying processes responsible for such behavioral patterns remain unclear. The authors propose that organizational crowding tends to generate competitive pressure that results in social overload for individuals, who in turn divide time and energy among many groups while reducing the time spent in each. The social overload thesis predicts integration, rather than mutual exclusion of groups, when experiencing competition. A large-scale event participation dataset from 11 major U.S. technology clusters over a period of 10 years is used to test these hypotheses. The results support the mediating role of competition in the relationship between population size and participation intensity. The authors demonstrate the impact of competition on network structure.
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Ecological Interactions Drive a Power‐Law Relationship Between Group Size and Population Density in Social Foragers
ABSTRACT Past work has shown that group formation in foraging animals aids in resource acquisition and reduces the number of interactions with predators. However, group formation can also increase competition for resources among group members. Here, we model how the individual costs and benefits of group formation drive group size. Our model predicts that when competition for resources occurs within and between groups, forager group size will exhibit a one‐third power‐law relationship with population abundance. However, if groups form due to intragroup competition and predation, we predict either a one‐half power‐law relationship with population abundance or a constant group size depending on the coupling between predator and prey. Using empirical data on group foraging birds and ungulates, we found a scaling relationship consistent with the one‐third power‐law, suggesting that hierarchical competition drives the average group size. Our results support work highlighting the importance of density‐dependent group formation in maintaining population stability.
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- Award ID(s):
- 2316602
- PAR ID:
- 10593800
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 28
- Issue:
- 4
- ISSN:
- 1461-023X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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