How Necking Shaped the Giraffe
The first time I saw a free-living giraffe was in Tanzania’s Arusha National Park, where I was astounded by a yellow-and-brown head gliding gracefully and, it seemed, impossibly high above the tops of tall acacia trees. That was 11 years ago and underscored why the giraffe has remained one of my favorite animals. But it wasn’t just my African experiences that kept the giraffe in my graces.
As an evolutionary biologist and professor, I have put Giraffa camelopardalis on stage in my classrooms—well, not literally—as the embodiment of how natural selection has produced a creature that on the one hand is spectacularly adapted to its peculiar ecological niche and on the other is an example of evolution’s “clumsy, wasteful and blundering” process, to borrow Darwin’s own words. It’s sometimes assumed those blunders result from mutations or evolutionary errors. But in fact they result from history: the fact that at any given point natural selection has no choice but to work from what is already available. More than most animals, giraffes reflect the fact that organisms have not been created from scratch (or if they were, the Special Creator was notably inept). Rather, they have been cobbled together, via trial and success, from their historical antecedents.
Giraffes have long enjoyed a special place in the hearts of evolutionists for another reason: as a real-life example of how to distinguish Darwinian from Lamarckian evolution. It turns out, however, the story isn’t quite so simple; indeed, nothing about these fascinating and bizarre animals is. A close look at their private
