Saturday, September 13, 2008

You can't possibly still think hyenas are ugly (part 2)

Due to formatting complications, this post had to be in two parts. Part 1 was the photos. This is part 2.

So after seeing all these pictures, it seems inconceivable that you could still think that hyenas are ugly. Are all of them gorgeous? Heavens, no, some of them are mangy, ragged, and certainly not pictures of grace. But isn't that true for any species (um, hello Amy Winehouse)? There's always a spectrum of variation... thankfully, because if there weren't, we'd all be bored silly.

Personally, I think hyenas look a lot like dogs, and what's not cute about that? Interestingly, they are more closely related to cats than dogs, although they aren't really closely related to either, as you can see in the carnivore phylogeny I've so cleverly ripped off from http://whozoo.org/mammals/.

The four species of hyenas (brown, striped, aardwolf, and our beloved spotted) are actually their own family. No, not "family" like June, Ward, Wally, and the Beav...there are no potluck dinners among this group. I mean "family" in the phylogenetic sense, as in "kingdom-phylum- class-order-FAMILY-genus-species" (perhaps you remember the mnemonic from high school biology, "King Philip Comes Over For Good Soup"?). These are taxonomic categories of increasing specificity—it's how scientists keep the millions of species in the world organized. So spotted hyenas are in the kingdom Animalia, the phylum Chordata, the class Mammalia, the order Carnivora, the family Hyaenidae, the genus Crocuta, and the species crocuta. But that's a bit of a mouthful, so species are typically referred to by just their genus and species name, a la Homo sapiens. Phylogenetic trees, like the one above, show the evolutionary paths of species...when and where they diverged from other species, and who their closest relatives are. This particular tree moves from left (oldest) to right (most recent). For example, you can see that the hyena's closest relative is, surprisingly, the mongoose. Fur seals are more closely related to sea lions than they are to walruses because the divergence between fur seals and sea lions is more recent than the divergence between their ancestors and walruses. And it's possible that that sentence made no sense to anyone but me.

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Coming soon...

1 comment:

DPP said...

You're an edgy Bill Nye and I love it.


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