Humpback whales, Maui, Hawaii

© Flip Nicklin/Minden Picture

Migrating giants. Humpback whales in Maui, Hawaii

If you ever want to feel insignificant, just think about the sheer size of a humpback whale. With adults growing up to 56 feet long, humpback whales are one of the biggest mammals on Earth. In February, Hawaii celebrates the return of these migrating giants with its Maui Whale Festival. This month-long event encourages people to get involved in conservation efforts and includes whale-watching tours, allowing closer views of these beautiful creatures.

A species of baleen whale, humpback whales are known for their haunting, elaborate songs, which travel vast distances through the ocean. It is only the males that sing and each whale population has its own song. Although the exact purpose is still a mystery, it is thought the songs might allow them to communicate with other whales over vast distances and help navigate new areas. These great leviathans of the deep also share a common ancestor with one of the world's biggest land mammals—they are distant relatives of the hippopotamus.