A new Yale study provides a fuller picture of the genetic changes that shaped the evolution of the human brain, and how the process differed from the evolution of chimpanzees. Using advanced techniques, researchers also were able to track how HARs interact with genes and human neural stem cells, which allowed them to identify gene targets for nearly all HARs — a significant advance in the study of human evolution. Many HAR gene targets are active in the developing human brain and are linked to processes such as formation of neurons and maintaining communication between neurons. “Our findings also show that HAR gene targets are expressed in particular cell types in the developing human brain, including cell types that may have contributed to the increased size of our brain,” Pal concluded. Now, this opens up many new avenues for us to understand how HARs contributed to the evolution of the brain.”