Question

Do all animals develop from embryos?

Answer 1

Human embryos resemble those of many other species because all animals carry very ancient genes. These genes date back to the origin of cells, which are expressed during a middle phase of embryonic development, according to two separate papers published in this week's Nature.

Answer 2

Human embryos resemble those of many other species because all animals carry very ancient genes. These genes date back to the origin of cells, which are expressed during a middle phase of embryonic development, according to two separate papers published in this week's Nature.