The excessiveness of the giraffes’ necks did not arouse the slightest debate for a long time. Darwin himself was convinced that it had gradually appeared in this ruminant to facilitate its access to food from large trees. However, this theory is no longer unanimous today, and a discovery published in the journal Science brings a whole new reading to this evolution.
Study scientists analyzed the skull and vertebrae of fossilized bones of a very ancient herbivore, Discokeryx xiezhi, discovered a few years ago in northern China. The species, which lived around 16.9 million years ago in the savannah, is considered the first version of the giraffe. His anatomical analysis revealed some particularly interesting things, especially about the primary purpose of his unique neck.
The neck of the Discokeryx xiezhi was indeed not designed to grapple the foliage in height, but rather to strike. And hit hard. Enough to beat all his congeners and mate first with the females.
Concrete cervical vertebrae
Scientists have indeed discovered that this ancestor of the giraffe had a kind of helmet with thick bones on the top of the skull and extremely thickened cervical vertebrae. A complex structure particularly suitable for high-speed headbutts.
For the members of the study, no doubt: like deer, sheep or even bison, this bone structure was used in a kind of mating duels. The males with stronger and longer necks beat their rivals every time, mate with the females and, gradually, transmitted their genes from generation to generation, describes the German media Deutsche Welle. Natural selection has done the rest through the ages, lengthening the necks of these elegant mammals to extreme proportions.