Evolution

The coelacanth (Latimeria chalumnae and Latimeria menadoensis) is called a living fossil because it closely resembles its ancestors, which lived 300 million years ago. Long thought extinct, the coelacanth resurfaced in 1938 when it was caught in a net off the coast of Africa. Even now, it's difficult to find a coelacanth because these ancient fish live deep in the ocean, often in caves.

Coelacanths also have four very large, thick fins, which scientists have long thought were a sign that this fish was a stepping stone in the move from water to land.

Researchers sequenced the genome of coelacanths, and compared coelacanths and lungfish (a fish with lungs) to land based animals. As it turns out, lungfish were more closely related to land based animals, suggesting that perhaps lungs were more important than legs in getting animals out of the water.

Photo courtesy of:

http://vertebrates.si.edu/fishes/coelacanth/coelacanth_wider.html

Sources:

http://www.bbc.co.uk/news/science-environment-22184556

http://www.sciencenews.org/view/generic/id/349739/description/News_in_Brief_Coelacanth_is_not_closest_fishy_relative_of_terrestrial_animals

http://vertebrates.si.edu/fishes/coelacanth/coelacanth_wider.html