Primate Sociality In Evolutionary Theory
The Role of Primate Sociality in Evolutionary Theory
Introduction
Some animals, and more specifically primates, have been noted for having brains of an uncommonly large size. One explanation for this phenomenon is the ‘social brain’ or ‘social intelligence’ hypothesis, which states that brain sizes have increased in order to handle the demands of sociality (Lindenfors 2005; Pérez-Barbería et al. 2007). The increase in brain size can be attributed to the computational power needed to track others in the group and ensure individual and species survival (Müller & Soligo 2005; Pérez-Barbería et al. 2007). Sociality in primates – and thus also in humans – has then some evolutionary basis. This bibliography, and my final literature review, …show more content…
Here we determine correlates of sociality and nonsociality in rodents as a model to infer causes of sociality in primates. We found sociality to be most strongly associated with large-bodied arboreal species that include a significant portion of fruit in their diet. Fruits and other plant products, such as flowers, seeds, and young leaves, are patchily distributed in time and space and are therefore difficult to find. These food resources are, however, predictable and dependable when their location is known. Hence, membership in a social unit can maximize food exploitation if information on feeding sites is shared. Whether sociality evolved in the primate stem lineage or whether it was already present earlier in the evolution of Euarchontoglires remains uncertain, although tentative evidence points to the former scenario. In either case, frugivory is likely to have played an important role in maintaining the presence of a social lifestyle throughout primate evolution. Am J Phys Anthropol
128:399–414, 2005. © 2005 Wiley-Liss, Inc.
Neocortex evolution in primates: the ‘social brain’ is for females
Patrik Lindenfors*,†
Department of Biology, University of Virginia, Gilmer …show more content…
The “social brain hypothesis” argues that maintaining group cohesion is cognitively demanding as individuals living in groups need to be able to resolve conflicts that impact on their ability to meet resource requirements. If sociality does impose cognitive demands, we expect changes in relative brain size and sociality to be coupled over evolutionary time. In this study, we analyze data on sociality and relative brain size for 206 species of ungulates, carnivores, and primates and provide, for the first time, evidence that changes in sociality and relative brain size are closely correlated over evolutionary time for all three mammalian orders. This suggests a process of coevolution and provides support for the social brain theory. However, differences between taxonomic orders in the stability of the transition between small-brained/nonsocial and large-brained/social imply that, although sociality is cognitively demanding, sociality and relative brain size can become decoupled in some cases. Carnivores seem to have been especially prone to this.
Social Bonds of Female
Introduction
Some animals, and more specifically primates, have been noted for having brains of an uncommonly large size. One explanation for this phenomenon is the ‘social brain’ or ‘social intelligence’ hypothesis, which states that brain sizes have increased in order to handle the demands of sociality (Lindenfors 2005; Pérez-Barbería et al. 2007). The increase in brain size can be attributed to the computational power needed to track others in the group and ensure individual and species survival (Müller & Soligo 2005; Pérez-Barbería et al. 2007). Sociality in primates – and thus also in humans – has then some evolutionary basis. This bibliography, and my final literature review, …show more content…
Here we determine correlates of sociality and nonsociality in rodents as a model to infer causes of sociality in primates. We found sociality to be most strongly associated with large-bodied arboreal species that include a significant portion of fruit in their diet. Fruits and other plant products, such as flowers, seeds, and young leaves, are patchily distributed in time and space and are therefore difficult to find. These food resources are, however, predictable and dependable when their location is known. Hence, membership in a social unit can maximize food exploitation if information on feeding sites is shared. Whether sociality evolved in the primate stem lineage or whether it was already present earlier in the evolution of Euarchontoglires remains uncertain, although tentative evidence points to the former scenario. In either case, frugivory is likely to have played an important role in maintaining the presence of a social lifestyle throughout primate evolution. Am J Phys Anthropol
128:399–414, 2005. © 2005 Wiley-Liss, Inc.
Neocortex evolution in primates: the ‘social brain’ is for females
Patrik Lindenfors*,†
Department of Biology, University of Virginia, Gilmer …show more content…
The “social brain hypothesis” argues that maintaining group cohesion is cognitively demanding as individuals living in groups need to be able to resolve conflicts that impact on their ability to meet resource requirements. If sociality does impose cognitive demands, we expect changes in relative brain size and sociality to be coupled over evolutionary time. In this study, we analyze data on sociality and relative brain size for 206 species of ungulates, carnivores, and primates and provide, for the first time, evidence that changes in sociality and relative brain size are closely correlated over evolutionary time for all three mammalian orders. This suggests a process of coevolution and provides support for the social brain theory. However, differences between taxonomic orders in the stability of the transition between small-brained/nonsocial and large-brained/social imply that, although sociality is cognitively demanding, sociality and relative brain size can become decoupled in some cases. Carnivores seem to have been especially prone to this.
Social Bonds of Female