For example, in 1821, Geoffrey St. Hilaire was the first scientist to publish the observation that some bird embryos exhibited evidence of tooth formation, but his contemporaries considered his ...

All vertebrate embryos follow a common developmental path due to their common ancestry. All have a set of very similar genes (the homeobox genes) that define their basic body plan. As they grow ...

"We can begin to understand more about one of the most fascinating reproductive strategies that kangaroos have, which is that the embryo can stay in suspended animation for months inside the ...