Cool Critter: Aye-aye
Years ago, when my high school played our rival high school, we had a cheer that began, “Aye Aye Aye Aye….” The rest of the cheer is totally inappropriate for this post, but I hear that opening line whenever I think of this month’s cool critter, the aye-aye.
The aye-aye (pronounced “eye-eye”), a native of Madagascar, is the largest nocturnal primate* in the world. That’s not particularly impressive since the little guys tip the scales somewhere between 5 ½ and 6 ½ pounds, but ya know, it could come in handy on “Jeopardy” someday.
Aye-ayes are adorable gremlin-like critters with long bushy tails, big eyes, huge ears, large hands and middle fingers that are three times longer than their other fingers. They spend their days sleeping in nests high in the rain forest canopy and spend their nights foraging for nuts, fruit, fungi, nectar, seeds, and insect larvae (a.k.a. grubs).
As our devoted readers know, our standards for the coolness of our Cool Critters are pretty freaking high. The aye-aye, like the African Wild Ass, has a fabulous name, but it’s the aye-aye’s grub-hunting style that earns it Cool Critter status.
To find grubs in trees, aye-ayes use a technique known as “percussive foraging.” They walk along a branch and tap their extra long middle finger quickly against the wood, and then they listen. When the aye-aye hears the sounds of a grub tunnel inside the wood, it goes to town, gnawing through the branch until the tunnel is visible. To get the grubs, the aye-aye sticks its middle finger into the hole, hooks a few grubs, and brings the snack to its mouth.
Aye-ayes’ bodies are totally designed for this style of foraging. Their long, skinny middle fingers move independently of the rest of the aye-aye’s fingers, like a built-in tool. Aye-ayes use their middle fingers to skewer prey, to groom and to drink (by dipping their fingers in liquid and quickly bringing it to their mouths). The aye-aye’s large hands allow it to use one hand to tap and extract prey while the other hand keeps the aye-aye from falling. Its huge, moveable ears allow the foraging animal to tune into the echoes from the tapping to locate insect tunnels. Its long incisors never stop growing, all the better to gnaw through branches. And finally, aye-ayes have a nictitating membrane—also known as a third eyelid—to keep their big eyes moist and to protect them from flying wood shards (a hazard of vigorous gnawing).
All the things that make the aye-aye a Cool Critter have earned it a very different reputation in its native land. According to legend, the aye-aye is a symbol of evil and death. Some say that an aye-aye’s appearance in a village means that a villager will die. Others say that aye-ayes sneak into houses during the night and puncture peoples’ aortas with their middle fingers. Either way, it is believed that the only way to protect oneself and one’s village from the evil aye-aye is by killing the aye-aye immediately.
This threat has never stopped the aye-ayes. The mischievous little critters have always sauntered through villages and raided coconut plantations. Of course, they have been killed. Now, as the aye-ayes’ rainforest habitat is being destroyed, more and more aye-ayes are sneaking into villages—and more and more aye-ayes are killed. And so the aye-aye is endangered.**
*The aye-aye is actually a prosimian, a suborder of primates that aren’t monkeys or apes. Lemurs, bushbabies and tarsiers are also prosimians. Aye-ayes have the largest brain of the prosimians. By the way, aye-ayes have color vision, a unique trait for a nocturnal animal.
** The aye-aye is listed as “near threatened” on the IUCN Red List.