The World's Smallest, Cutest...Rodent

May 27, 2009 — -- Stand up -- or, perhaps, lean in very closely -- and meet the Pigmy Jerboa, a little critter described as the world's smallest rodent.

If you live in western Pakistan, you probably won't be impressed. They're all over the place there. But they qualify as pretty amazing animals. And the rest of the world saw very little of them until a video was posted on YouTube --- and is now all over the Web.

"Behold the pygmy jerboa," wrote columnist Andrew Sullivan in his "Daily Dish" blog at The Atlantic, "like a rabbit's face on tweety-pie's body."

In fact, say scientists, that's what makes them seem cute to us. "People have a strong tendency to like short faces and big eyes," said Rob Voss, curator of mammalogy at New York's American Museum of Natural History, "because they resemble human babies."

Hopping Mad

But why those big hind legs? The better to hop with, my dear.

It can jump more than nine feet, says the World Wildlife Fund -- pretty good when you consider that it's only about an inch long, on average. It uses its long tail to balance.

"Generally, you find hopping animals in deserts," said Voss. "There's not a lot of overgrowth, so they don't bump into things. Hopping is a very energy-efficient way of avoiding predators." The pygmy jerboa is native to Pakistan and Afghanistan, but it has cousins living from the Sahara Desert to Kazakhstan.

Jerboas are afraid, above all, of owls, which swoop down from the sky almost silently and snatch them in an instant.

As a matter of self-protection, most jerboas have highly evolved hearing. If you took an X-ray of one, said Voss, you'd see the skull is "a set of teeth -- mounted in front of giant ears."

The Tale of the Pygmy Jerboa

Voss also points out that the jerboas are a great example of convergent evolution -- unrelated animals that develop similar characteristics because they live in similar conditions.

In all the world's major desert regions, he points out -- from Australia to central Asia to northern Africa to the desert southwest of the United States -- you'll find hopping rodents. They hop because if they didn't, they'd die out.

But enough seriousness. Sullivan, after all, labeled his Jerboa post as a "mental health break." The real bottom line is all the people who left comments like:

"Ahhh!! He is so, so, so, so cute!"