#Hints at jaw evolution found in marsupials and monotremes
“#Hints at jaw evolution found in marsupials and monotremes” Images of the join between the ear bones and upper jaw in the echidna at hatching. The left image shows the cartilages in blue, while the right shows the expression of type II collagen (green) and Sox9 (red), both necessary for cartilage development. Credit: Anthwal et…