rock, n.Trivia

Crocodiles swallow rocks to help them dive deeper

Dinosaurs swallowed large rocks that stayed in their stomach to help churn and digest food.

There are microscopic living things in solid rock up to 7 km deep, called Endoliths. So little energy is available they undergo cell division once every 100 years, and some may only divide once every 10,000 years.

Otters often have a favorite rock which they store under their arm in a little pouch when not in use