The thyroid gland is part of the endocrine system (along with the adrenal glands, hypothalamus, pituitary, ovaries, and testes, and other endocrine organs). The thyroid gland releases hormones into ...

A worm-like creature preserved in ancient rock has just been identified as the oldest known relative of insects, spiders and crustaceans.

The integumentary system is the body’s outermost layer. Composed of skin, hair, nails, glands, and nerves, its main job is to protect your insides from elements in your environment, like pollution and ...

So what are these strange creatures, and what are their captive requirements? They are actually annelids, which means they are related to earthworms. However, unlike the free-living members of that ...