This article published in Biological Psychiatry discusses a new technique to analyze phenotypic differences between humans and other non-human primates/hominids. For the purpose of studying human brain evolution and potential evolutionary links between humans and non-human primates, the researchers made use of induced pluripotent stem cells (iPSC). iPSCs are responsible for the formation of neocortical pyramidal neurons--which lead to species-specific phenotypes. These special category of neurons display morphological variations across various cortical layers in the brain, and are known to be species-specific. Therefore, neocortical pyramidal neurons may offer a unique neurological approach to test evolutionary hypotheses involving humans and non-human primates. This review article also underscores that the morphology of pyramidal neurons is impaired in neurological and psychiatric disorders; due to this characteristic, iPSCs may contribute insights towards to both human medicine and evolutionary relationships. Exciting!