This explanation also makes clear to the question why giraffes develop more necks than their limbs. If giraffes evolved simply to feed on the taller branches, their legs would have elongated as well, commensurate with the increase in their necks.
Simmons and Altwegg, the proponents of the idea, argue that giraffes initially developed for the purpose of foraging but later turned to the goal of acquiring mating subjects. To support their theory, these two scientists led a study done in “The American Naturalist in Namibia”. This study concludes that male giraffes have a heavier neck than females (with the same body mass). This study also showed that only in the case of males, the neck continued to develop throughout their lives.
There is only a small difference in the length of the male and female giraffes so the scientific community is not fully convinced by the above theory. Therefore, this centuries-old puzzle still needs more research for a more convincing answer.
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