New study shows how friendlier facial expressions may have helped humans evolve

A new study suggest that ability to convey kindness through facial expressions may have been a key factor in human evolution. The study was conducted by Matteo Zanella and a team of researchers at the University of Milan, and published this week in Science Advances. The team compared genetic data from human stem cells with samples from the remains of two Neanderthals and one Denisovan, a sister species to Neanderthals found in central Asia. They specifically focused on the BAZ1B gene, which has been connected to Williams-Beuren syndrome, a condition that causes people to develop wide mouths and small noses that give a generally kind and welcoming impression. The BAZ1B gene has also been associated with the evolution of two extra muscles in dogs that allow them to widen and narrow their eyes in expressive ways, something wolves aren't able to do.