It is generally thought that the plesiadapiformes were not true primates but perhaps led to them. These earliest primates relied much more on sense of smell than later primates did.
"Most explanations on the evolution of primate brains are based on data from living primates," said lead author Mary Silcox, an anthropologist at the University of Winnipeg and research associate at UF's Florida Museum of Natural History. "There have been all these inferences about what the brains of the earliest primates would look like, and it turns out that most of those inferences are wrong."
Researchers used CT scans to take more than 1,200 cross-sectional X-ray images of the skull, which were combined into a 3-D model of the brain.
"A large and complex brain has long been regarded as one of the major steps that sets primates apart from the rest of mammals," said Florida Museum vertebrate paleontologist and study co-author Jonathan Bloch. "At our very humble beginnings, we weren't so special. That happened over tens of millions of years."
Thursday, June 25, 2009
Brain Evolution in Early Primates
Work by University of Florida vertebrate palaeontologists Mary Silcox and Jonathan Bloch suggest that the early primate brain may not have evolved in quite the way we think it did. The story, in Science Daily, has this to say: