Community Evolution and the Origin of Mammals

  title={Community Evolution and the Origin of Mammals},
  author={Everett Claire Olson},
  • E. C. Olson
  • Published 1 March 1966
  • Environmental Science, Geography
  • Ecology
The evolutionary course from primitive pelycosaurian reptiles through therapsids to mammals can be profitably studied in relationship to modifications of the structure of the communities in which these reptiles existed. For this purpose the community is defined in very board terms. Three types of communities are recognized upon the basis of the nature of the food chain. Each has an important tetrapod component. Early phases of the evolution that culminated in mammals took place in communities… 

The environment of Ramapithecus in Africa

Comparisons with the community structure of modern habitats suggest that the environment of the early Miocene fauna of Songhor, and the primitive apes associated with it, was probably a type of lowland forest, and that several genera of Eurasian apes, including Ramapithecus, made a similar environmental change at the same time.

The Oldest Caseid Synapsid from the Late Pennsylvanian of Kansas, and the Evolution of Herbivory in Terrestrial Vertebrates

These results demonstrate for the first time that large caseid herbivores evolved from small, non-herbivorous caseids, and are mirrored by three other clades, documenting multiple, independent, but temporally staggered origins of herbivory and increase in body size among early terrestrial tetrapods, leading to patterns consistent with modern terrestrial ecosystem.

The origin and early radiation of the therapsid mammal‐like reptiles: a palaeobiological hypothesis

  • T. Kemp
  • Environmental Science, Geography
    Journal of evolutionary biology
  • 2006
An hypothesis is presented in which the origin of the therapsids resulted from a correlated progression of character evolution leading to higher levels of metabolic activity and homeostatic regulation of the body.

Mesozoic Mammalian Evolution

The evolutionary history of Triassic terrestrial vertebrate faunas is one of change from dominance of the mammallike reptiles, therapsids, in the Early Triassic to archosaurian dominance at the end of the period.


The Mesozoic history of the Mammalia is approximately twice as long as the Cenozoic. Because of their small size the remains of early mammals were often overlooked. In the last two decades

Dinocephalian stage in the history of the Permian tetrapod fauna of Eastern Europe

  • V. Golubev
  • Environmental Science, Geography
    Paleontological Journal
  • 2015
The first tetrapods entered continental communities as consumers of the highest order, forming the subdominant and aquatic tetrapod communities. At the end of the Carboniferous, herbivorous tetrapods


  • M. Benton
  • Environmental Science, Geography
  • 2002
Benton, M. J., 1979. Ecological succession among Late Palaeozoic and Mesozoic tetrapods. Palaeogeogr., Palaeoclimatol., Palaeoeco!., 26: 127--150. Natural selection and the development of new taxa

Evolution of Herbivory in Terrestrial Vertebrates: Herbivory in terrestrial vertebrates: an introduction

  • H. Sues
  • Environmental Science, Geography
  • 2000
Chemical analyses of hard tissues (such as extraction of preserved stable carbon isotopes) increasingly are providing significant new data for inferring diet in extinct animals, increasing confidence in the robustness of these reconstructions.