#primelephas

Primelephas — Late Miocene- Early Pliocene (7-2 Ma)

I love elephants. I came out of hiatus just to say that. They’ve always been one of my favorite animals, and prehistoric proboscideans were one of the first paleontology topics I was really interested in as a kid. That probably shows, considering this is the third one I’ve drawn for this blog. BUT, this is the first true elephant to be featured here, and fittingly enough, its name means “first elephant.” Let’s pretend I did that on purpose and didn’t realize it as I was typing this just now.

Primelephas is pretty mysterious, even though it only went extinct pretty recently. We know a lot about the Miocene/Pliocene as a whole, but we only have a few remains of Primelephas. Those few remains have been found in Africa, although it was probably more widespread than that. It packed the setup we’ve come to expect of an elephant: A long, grasping trunk that doubled as a bendy straw, big, sturdy legs, and a stocky body. We can pretty reasonably assume it was mostly hairless, too, considering the environment it lived in. It sounds an awful lot like a modern elephant, doesn’t it? The main difference is the pair of tusks on the tip of its jaw. Elephant tusks come in all shapes and sizes, so I tried to draw this one with a pair of upper tusks that properly show off the bottom pair.  

Oh, also, Primelephas is the common ancestor of three genera of elephant: Mammuthus, Elephas, and Loxodonta. I mention this because those are, in order, the Woolly Mammoth, the Asian Elephant, and the African Elephant. That’s why it looks so much like a modern elephant, because it’s only one step removed. The best part about the Cenozoic is how well we understand the taxonomy of the animals who live in it. Not to mention, cats evolved during the Cenozoic, and I personally find that very important.

If you don’t know elephant taxonomy (and I don’t blame you if you don’t), you might find it weird that 1) African and Asian elephants are different genera, I didn’t know that until recently, and, 2) the Woolly Mammoth shares such a recent common ancestor with them. The other furry proboscideans, the Mastodons, diverged from their modern cousins during the Oligocene, around 30 million years ago, so it would make sense if mammoths did that, too. Except, they didn’t, because there are no rules in biology. Here’s a chart showing the family tree of modern elephants. Like the last time I did one of these, it’s very simplified and only shows the stuff that’s relevant.

So, as you can see, mammoths are descended from Primelephas, just like modern elephants. Not only that, but mammoths are more closely-related to Asian elephants than Asian elephants are to African elephants. Considering mammoths evolved so recently from an ancestor who most likely only had sparse hair like a modern elephant, and considering just how close they are to Asian elephants, it’s very likely that heavier fur is a trait that’s relatively easy for natural selection to “turn on” or “turn off” in proboscideans. Also keep in mind this happened more than once, because Mastodons did it too. This is something we’ve studied pretty closely, and this is actually tapping on the window of a really cool subject that will have to be covered another day. For now, I have to crawl back into my hiatus cave and do some more research. I’ll see you all next week!

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