Schematic of the differentiation protocol and the stages at which single-cell RNA-seq data were collected (A), along with descriptions of the human and chimpanzee cell lines used (B), a diagram of the overall study design (C), and cell images from one human cell line and one chimpanzee cell line at each stage of differentiation (D). Pluripotent cells (Time 0) and mesenchymal cells (Time 1) are phase contrast images at 4X magnification, and osteogenic cells (Time 2) are stained with Alizarin Red and zoomed out to display the entire cell culture well. Silhouette images were adapted from http://phylopic.org/ and courtesy of T. Michael Keesey and Tony Hisgett (http://creativecommons.org/licenses/by/3.0/).</p
