Evolution of Human Brain

The correlation suggests that scientists studying the evolution of the human brain should look to genes considered recent by evolutionary standards and early stages of brain development.
"There is a correlation between the new gene origination and the evolution of the brain," said Manyuan Long, PhD, Professor of Ecology & Evolution at the University of Chicago and senior author of the study in PLoS Biology. "We're not talking about one or two genes, we're talking about many genes. This is a process that is continually moving and changing our brain."
Scientists have long sought to solve how the brain evolved to have the anatomical features and functional ability that separate humans from their primate ancestors. With the completion of the Human Genome Project in 2003 and the growing availability of genome sequences for primates and other species, researchers have looked to genetics for answers on brain evolution.
From these studies, many scientists have hypothesized that differential regulation of conserved genes shared across species, rather than the arrival of new species-specific protein-encoding genes, was responsible for the dramatically different human brain. But in a 2010 study, Long's laboratory discovered that the younger species-specific genes could be just as important as older conserved genes to an organism's development.
For the PLoS Biology paper, researchers merged a database of gene age with transcription data from humans and mice to look for when and where young genes specific to each species were expressed.