Mosaic evolution of brain structure in mammals

  title={Mosaic evolution of brain structure in mammals},
  author={Robert A. Barton and Paul H. Harvey},
The mammalian brain comprises a number of functionally distinct systems. It might therefore be expected that natural selection on particular behavioural capacities would have caused size changes selectively, in the systems mediating those capacities. It has been claimed, however, that developmental constraints limited such mosaic evolution, causing co-ordinated size change among individual brain components. Here we analyse comparative data to demonstrate that mosaic change has been an important… 

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Primate mosaic brain evolution reflects selection on sensory and cognitive specialization

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  • R. Barton
  • Biology, Psychology
    Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 1998
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Linked regularities in the development and evolution of mammalian brains.

Analysis of data collected on 131 species of primates, bats, and insectivores showed that the sizes of brain components, from medulla to forebrain, are highly predictable from absolute brain size by

Evolution of the Cerebellum in Primates: Differences in Relative Volume among Monkeys, Apes and Humans

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Neocortex size and behavioural ecology in primates

  • R. Barton
  • Biology, Psychology
    Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 1996
It is confirmed that neocortex size and social group size are positively correlated once phylogenetic associations and overall brain size are taken into account, and among diurnal haplorhines its size is positively correlated with the degree of frugivory.

Cortical Organization in Insectivora: The Parallel Evolution of the Sensory Periphery and the Brain

  • K. Catania
  • Biology
    Brain, Behavior and Evolution
  • 2000
Insectivores are traditionally described as a primitive group that has not changed much in the course of mammalian evolution. In contrast, recent studies reveal a great diversity of sensorimotor

The evolution of isocortex.

  • J. Kaas
  • Biology
    Brain, behavior and evolution
  • 1995
Numbers of areas have increased independently in several branches of mammalian evolution, and the functioning of large brains may be enhanced by having more subdivisions, over many generations new areas may emerge from old by the formation of functionally distinct modules within areas, followed by the fusion of modules to ultimately form separate ones.

Evolutionary radiation of visual and olfactory brain systems in primates, bats and insectivores.

  • R. BartonA. PurvisP. Harvey
  • Biology, Environmental Science
    Philosophical transactions of the Royal Society of London. Series B, Biological sciences
  • 1995
It is concluded that activity timing, diet and habitat have each played a role in the evolutionary radiation of mammalian sensory systems, but with varying effects in the different taxa.

Relative Volume of the Cerebellum in Dolphins and Comparison with Anthropoid Primates

Compared relative cerebellum volumes in two cetacean species, the bottlenose dolphin and the common dolphin, are compared with published data from anthropoid primates to suggest that there is possibly expansion of brain structures independent of strictly allometric processes.

A universal scaling law between gray matter and white matter of cerebral cortex.

  • K. ZhangT. Sejnowski
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2000
The predicted power law with an exponent of 4/3 minus a small correction for the thickness of the cortex accurately accounts for empirical data spanning several orders of magnitude in brain sizes for various mammalian species, including human and nonhuman primates.

Volume comparisons in the cerebellar complex of primates. II. Cerebellar nuclei.

From Insectivora to man, the MCN was the least progressive and the LCN the most progressive, and with reference to evolutionary trends in primate phylogeny.