Thanks to a cold environment, which causes a slow metabolism, bowhead whales (Balaena mysticetus) can live for more than 200 years - nearly 3 times longer than the average human, making it the longest-lived mammal.

Bowhead whales can grow 14 to 18 m (46 to 59 ft) in length, and unlike most whales, they lack a dorsal fin. This thick-bodied species can weigh from 75 to 100 tonnes (82 to 110 US tons). They live entirely in fertile Arctic and sub-Arctic waters, unlike other whales that migrate to low latitude waters to feed or reproduce. The bowhead also has the largest mouth of any animal.

Of course, following around a whale to measure how long it lives is practically impossible. Researchers discovered this amazing feature in 2007, when a 15 m ...

Meet the cassowary. These are flightless birds native to the tropical forests of New Guinea and northeastern Australia. There are three extant species. The most common of these, the southern cassowary, is the third tallest and second heaviest living bird, smaller only than the ostrich and emu.

All three species have horn-like but soft and spongy crests called casques on their heads, up to 18 cm (7 inches), which serves several purposes. The most interesting being that the wedge-shaped casque may have evolved to protect the head of this animal by deflecting falling fruit, since cassowaries spend a lot of time under trees where seeds the size of golfballs or larger fall from heights of up to 30 metres! ...