Why are giraffes’ necks so tall?

There are two main scientific theories as to why giraffes’ necks are so tall. The first was proposed by Charles Darwin and suggests that due to intense competition from rival creatures for foliage under two metres high, giraffes’ common ancestor slowly evolved a longer neck in order to access untapped leaf reserves – with only the more successful, longer necked animals feeding efficiently. The second theory is that giraffes evolved long necks as a secondary sexual characteristic, giving males an advantage in physical combat and therefore granting access to more sexually receptive females to reproduce.