The classic theory of why giraffes have such weirdly long necks goes like this: competition for food meant giraffes with the longest necks were more likely to survive. If longer necked giraffes could access the highest leaves and enjoy lunch even during hard times when leaves were scarce.
But there are other theories about the evolutionary driver of giraffes’ ridiculously long necks.
One theory suggests bigger, longer necks are better for battle. Male giraffes fight for dominance by swinging their necks and whacking each other. Hard. It’s incredible to watch—so graceful yet so vicious. Since longer necks with more muscle pack a bigger punch, the theory goes that bigger-necked giraffes who gain dominance were more likely to mate and pass on their genes.
But then a group of scientists decided to measure the differences in necks between male and female giraffes and discovered that female giraffes actually have proportionally longer necks than males.
The scientists suggested the females used their long necks to probe deeper into bushes to find the most nutritious food. Giraffes are notoriously picky eaters and only feed on the freshest leaves. Since female giraffes spend most of their adult lives either pregnant or providing milk for their calves—the longest neck could provide the bestest, freshest diet for mums. Maybe the evolutionary driver of long necks wasn’t male battles for dominance, but mama giraffes’ dietary needs.
And then, don’t forget that a very, very long neck gives giraffes a very, very good view of any predators. Giraffes also have enormous eyeballs on the end of those long necks—all the better to see you with.
I also have a theory. I have zero scientific evidence, but I think my theory is by and far the best.
Here goes:
I’ve long believed that giraffes don’t make noise. I wrote about this in my Beastly Puzzles: An Animal Guessing Game. “Giraffes can make noise, but rarely do.” Take another peak at the giraffe fight video. Despite all the whacking, they don’t make a single sound. Strange and amazing.
But I was wrong! Scientists have discovered that giraffes are making noise—we just can’t hear it. Giraffes hum at super low frequencies! Scientists believe these infrasonic sounds might be used for long-range communication.
So here’s my theory of the evolutionary driver of giraffes’ ridiculously long necks: like the world’s longest, most impressive infrasonic didgeridoo, giraffes’ necks evolved to produce better communications. Longer necks made better, more handsome sounds that travelled further for better herd communication. (Remember, this is just my theory—so quote me with caution.) This could explain why females have proportionally longer necks—they live in groups and need to communicate with their herd—whereas older, male giraffes are often solitary.
So which theory is right?
Maybe none of them. Or maybe they are all a little bit right. I’m no scientist, but I say more the merrier!
And to giraffes everywhere, I say “Keep those necks long and weird!”
Want to know more?
Here’s some reading:
Why do giraffes have long necks: https://www.wired.com/story/why-do-giraffes-have-long-necks/
Giraffes may be long-necked for fights: https://www.nytimes.com/2022/06/02/science/giraffe-neck-evolution.html
Female giraffes drove evolution to feed on most nutritious leaves: https://theconversation.com/female-giraffes-drove-the-evolution-of-long-giraffe-necks-in-order-to-feed-on-the-most-nutritious-leaves-new-research-suggests-227029
Giraffes spend their evenings humming to each other : https://www.newscientist.com/article/2058123-giraffes-spend-their-evenings-humming-to-each-other/
And a good video overview: