Ask Dr. Universe: What are axolotl?

Dear Dr. Universe: What do axolotl eat? What species are they? Do you think they are cute? — Erin, 10, Florida

Dear Erin,

An axolotl (ax-a-lot-l) is a creature with big frilly gills like a lion’s mane, tiny eyes with no eyelids, and a mouth in the shape of a smile. They come in lots of colors: pink, black, golden, or grey.

These animals have been nicknamed “the walking fish,” but they are not really fish. An axolotl is a type of salamander.

That’s what I found out from my friend Ed Zalisko. Zalisko earned his Ph.D. at Washington State University and is now a biology professor at Blackburn College in Illinois.

A salamander is a type of amphibian, a cold-blooded animal that has gills, can breathe air, and lives under water. We find axolotls mainly in Lake Xochimilco and Lake Chalco in Mexico. The species name is Ambystoma mexicanum.

Because humans need water to survive, that means there is less water left for some of the amphibians. Axolotls are actually a critically endangered species, Zalisko said.

There are many species of salamander that are part of the group Ambystoma. About a decade ago, Zalisko discovered a new kind of axolotl. These particular axolotls can hold their breath for a whole year!

Axolotls breathe through their gills and lungs and sort of inflate like a balloon. The kind that Zalisko discovered don’t let the air out.

“No one knows why they hold their breath so long,” he said about the BC Axolotl, named after Blackburn College.

When they puff up, they flip over on their bellies. That means when they eat, they eat upside down.

Upside down or right side up, axolotls actually eat all kinds of different things, Zalisko said. They are carnivorous, which means they eat meat. Some axolotls like to snack on snails, worms, insects, fish, and sometimes even other kinds of salamanders.

Finally, we explored your third question about axolotl cuteness.

“I think they are spectacularly cute,” Zalisko said. “And you can quote me on that. They just sit around most the time and look as cute as can be.”

In the lab, researchers can watch these amphibians develop in real time because the axolotl eggs are see-through. It’s kind of like looking through a window.

In addition to being cute, axolotls may be able to teach us a thing or two about how to re-grow limbs, like arms and legs. If an axolotl loses a leg, it can regenerate it. Who knows? Maybe one day you can help us learn more about these creatures.


Dr. Universe

“Ask Dr. Universe” is a science education project based out of Washington State University. Send questions to Ed Zalisko gives a special thanks to his teachers John H. Larsen Junior at Washington State University and Ron Brandon at Southern Illinois University who studied salamanders for many years.