"Cellular Anthropology" - Why do human and chimpanzee faces differ?

There is overwhelming evidence that the morphological differences between closely related species, including chimpanzees and humans, are not due to sequence changes in proteins, but to regulation of gene expression. Recently, researchers from Stanford University were interested in pinpointing how and when during development did differences in chimpanzee and human facial morphology manifest.

Using iPSCs (induced pluripotent stem cells), they created chimp and human cranial neural crest cells, and examined differences in gene enhancer regions. Published in Cell, their results suggest that there are around 1,000 species-biased enhancers near loci involved in craniofacial development and facial variation.