Reconstruction of ancient kiwi-sized primate skulls helped University of Florida researchers to solve an age-old miystery of evolution of large brains in apes into human species.
University of Florida paleontologists found clues in lemur-like primate skulls from the tropical forests of Wyoming about 50 million years ago, thought to be a link between primitive and advanced primates.
Arianna Harrington, a master’s student at the Florida Museum of Natural History on the UF campus, used CT technology to create the eight virtually reconstructed and dissected brains to show how an evolutionary burst including improved vision and more complex neurological function preceded an increase in brain size.
The findings, published in the Journal of Human Evolution, reconfirms the earlier findings by researchers who compared Australopithecus afarensis, the oldest hominid known and Victoriapithecus macinnesi, an Old World monkey skull showing similar brain sizes.
“It may be that these early specializations allowed primate brains to expand later in time. The idea is that any patterns we find in primate brain evolution could lead to a better understanding of the early evolution that led to the human brain,” said Harrington.
Adapiforms evolved from the earliest primate ancestors plesiadapiforms, which lived about 65 million years ago.
Adapiforms’ skulls differ from the earlier plesiadapiforms in having more forward-facing eyes.
The antomical features show that, while adapiforms placed relatively less emphasis on smell more similar to modern primate brains, the relative brain size was not so different from that of plesiadapiforms, said study co-author Jonathan Bloch, curator of vertebrate paleontology at the Florida Museum.