KNOXVILLE, Tenn. — Inside a small clear tube, a naked mole-rat decides to change direction. Contorting its wrinkled, hot-dog-shaped body, the animal nearly somersaults over itself and pokes out its head on the other side. It shows off four big teeth, sniffs the air and turns around again.
Watch a naked mole-rat for a while, and you’ll see this happen over and over and over. The nonstop movement and unusual characteristics — certainly not beauty — are what make mole-rats a hit with zoo visitors, especially children.
“They’re so ugly, they’re cute,” says Knoxville Zoo keeper Cathleen Wise. “You can’t help [look at them]. There’s always something to watch.”
The Knoxville Zoo joined a handful of zoos across the country showing off the strange creatures when it opened the “Naturally Naked Mole-Rats” exhibit on March 31.
Natives of Africa, naked mole-rats are the only eusocial mammals, meaning they live in a colony ruled by a queen, the only female who reproduces.
In the wild, they spend nearly all their time underground, but despite their name, they are neither moles nor rats. Mole-rats are more closely related to chinchillas, guinea pigs and porcupines.
There are several species of mole-rats, but only naked mole-rats are, well, naked or nearly hairless. Some other types of mole-rats are not eusocial and live alone or in smaller groups.
Naked mole-rats are about 3 to 4 inches long and can look — to put it politely — downright homely in large, up-close photographs that emphasize their wrinkly skin, walruslike teeth and lack of hair.
Zoos are spreading the critters to other zoos when their colonies grow too large and need to be split.
Knoxville got one colony of 16 animals from the Brevard Zoo in Melbourne, Fla., late last year and then another of 39 animals in March from the Rio Grande Zoo in Albuquerque, N.M.
The queen of the first colony already has had a litter, in which three babies survived. She’s pregnant again and is expected to give birth in the next few weeks.
The critters have been a big hit in Albuquerque, says Rick Janser, the zoo’s mammal curator. “There’s the gross-out factor, but once [people] start watching them, they’re fascinated by how active they are,” Mr. Janser says. “It’s not like the gorillas, but you usually have a large group of people watching them.”
Besides Brevard, the closest zoos to Knoxville with naked mole-rats include Louisville, Ky., Cincinnati and the National Zoo in the District.
“They’ve always been very popular, especially with kids, because they’re very active and unusual, always very busy,” says Sarah Glass, Knoxville’s curator of special exhibits and red pandas. “They’re just odd.”
The animals are displayed in a series of clear tubes and boxes.
“I love them. I just think they’re fascinating,” Miss Glass says. “It’s like watching mole-rat TV. Just watch them run around and do all the things they do.”
Children and their parents may know more about naked mole-rats than other zoo visitors. Disney’s cartoon show “Kim Possible” features Rufus, a naked mole-rat who likes to eat nachos.
Real naked mole-rats are vegetarians, do not live alone and would not make good pets — and they squeak and chirp.
Knoxville Zoo, 3500 Knoxville Zoo Drive, Knoxville, Tenn.; Exit 392 from Interstate 40; visit www.knoxville-zoo.org or call 865/637-5331.