Tiktaalik

evolution · ancient fish · transitional species · Devonian Period

Fish with limbs. Tiktaalik had the body of a fish but also had front limbs that looked like arms and hands, making it perfectly suited to live both in water and on land.

Living fossil bridge. Scientists call Tiktaalik a missing link because it shows exactly how fish gradually transformed into tetrapods, the first four-legged animals that could walk on dry ground.

Bigger than you'd think. Tiktaalik grew to be about 4 to 9 feet long, roughly the size of a modern crocodile, making it a pretty hefty creature for its time.

Clever design. It had a flat head like a crocodile and strong neck muscles, which helped it prop itself up and move across shallow water or muddy ground.