Why is the giraffe an example of evolution?
Likewise, how would Darwin explain the evolution of giraffes?
In terms of the giraffe example, Darwin's theory of evolution through natural selection would suggest that a giraffe was born with a longer neck by random chance. Having access to more food allowed the giraffe to live longer and reproduce more, ultimately leading to more long-neck giraffes.
Beside above, what animal did the giraffe evolve from? Some scientists have long presumed today's giraffe (Giraffa camelopardalis, right), which includes a handful of subspecies scattered throughout sub-Saharan Africa, evolved from an animal that looked like its close cousin the okapi (Okapia johnstoni, left), which lives in the tropical forests of central Africa.
In this way, why did giraffes necks get longer?
The latest theory – and it's a surprise this hasn't come up before, given biologists' fixation with it – is that the long necks are the result of sexual selection: that is, they evolved in males as a way of competing for females. Male giraffes fight for females by “necking”.
How would Lamarck explain giraffes?
If a giraffe stretched its neck for leaves, for example, a "nervous fluid" would flow into its neck and make it longer. Lamarck believed that the long necks of giraffes evolved as generations of giraffes reached for ever higher leaves.