Typically, animal skin appendages including hair, feathers, and scales are controlled by specific genes when an embryo is developing. There are some exceptions to this rule–including in crocodile ...

How can we explain the morphological diversity of living organisms? Although genetics is the answer that typically springs to mind, it is not the only explanation. By combining observations of ...

The earliest days after fertilization, once a sperm cell meets an egg, are shrouded in scientific mystery. The process of how a humble single cell becomes an organism fascinates scientists across ...