Marsupials are a missing link in vertebrate development

Marsupials were popular models for early development in the early 1900s , with classic morphological studies performed by notable embryologists such as J.P. Hill, C.G. Hartman, T.T. Flynn (Errol Flynn’s father) and E. McCrady. These workers were fascinated by the marsupial mode of blastocyst formation, which contrasts starkly with that of eutherians. One key difference [...]