They’re mouse-sized mammals, live in colonies, have a plant-based diet . . . any guesses? No? Okay, a few more clues—they’re native to the Horn of Africa, live underground, and have their own exhibit at the Seneca Park Zoo. Ding, ding, ding! That’s it—naked mole-rats. Residents at the zoo since 2018, they’re becoming more and more popular, and it’s easy to understand why.
Naked mole-rats are one of only two known eusocial mammals in the world, the other being the Damaraland mole-rat. Eusocial means that the animals live in large colonies with an intricate social organization system. Think of bees and ants—these insects are eusocial just like naked mole-rats and behave similarly. One female in the colony is responsible for breeding, and all the other members take part in caring for the offspring and colony. The Seneca Park Zoo has two colonies which add up to a total of twenty-two naked mole-rats, but they don’t intermingle—Zoologist Ryan Statt explains how tight-knit these colonies are and why.
“Besides the penguins, they’re probably the second most high maintenance animals we have here,” Statt says. “We have to wear gloves when we handle them and clean, because if one doesn’t smell like the rest of the colony, they’ll get kicked out. They’re territorial and will fill their colonies to the capacity they’re comfortable with based on how much room they have to work with.”
So, where are these colonies? Naked mole-rats burrow underground and create tunnel systems, delegating certain areas for certain things. Think of it in terms of a house.
“They have one chamber that we put food in, they have one that they use to go to the bathroom, and they have one that they all sleep in,” Statt says. “A dining room, bathroom, and bedroom. And they dictate how they orient themselves. When we first got them, we put the food in one box, and as a group, they systematically all moved the food to a different box and then they started eating it.”
Just as the naked mole-rats determine their own living arrangements, they determine their jobs as well. The group will choose a queen, and she will soon become larger than the others, making it easy to stand out. Whereas people can choose their careers—a teacher, a custodian, an astronaut— naked mole-rats are born into theirs.
“When they’re born, they do a job, and that’s all they do. They might dig tunnels for the rest of their life, gather food, or protect the colony form predators, but that’s all they do,” Statt says.
Living underground, there’s the chance that their tunnels may collapse. Statt believes this environment relates to their adaptation of prolonged breath holding.
“They can go without oxygen and hold their breath for almost twenty minutes, which is almost unheard of unless you’re talking about a whale or seal or something like that. And they don’t seem to have any ill effects from going without oxygen for that long,” Statt says.
The list of why these animals are so intriguing seems to be never-ending, and one big reason on that list is that they don’t get cancer. With a documented lifespan of up to thirty years, Statt explains they’re one of the few animals that don’t get the disease at all, and while the reason is unknown, it may be tied to their diet. “
They’re strict vegetarians,” Statt says. “They love sweet potatoes and things with a lot of water in them like watermelon, oranges, grapes, and cantaloupe, but water outside of their food is actually bad for them. If we were to spray them or get excess water in their home while cleaning and they walked through it, it can actually cause them to have seizures.”
Interested yet? There is so much more that can be learned about naked mole-rats at the Seneca Park Zoo. These little animals are located in the Animals of the Savanna building which also houses the giraffes, zebras, and white rhino. Find out more information online at senecaparkzoo.org
