Scientists already know enough about naked mole rats to put them in the "strange" category. The hairless ground-dwelling wonders are notable for being cold-blooded mammals that are practically immune to cancer and far outlive other rodents, reports Science Daily. Now scientists say they've observed the creatures surviving without oxygen, too—for as long as 18 minutes, reports NPR. How? They use an alternative fuel, and in a way that has never before been observed in vertebrates. Reporting in the journal Science, researchers explain they put naked mole-rats in a chamber with just 5% oxygen, a quarter of normal levels, which kills mice in minutes. The mole-rats were fine.
"They had more stamina than the researchers," says researcher Thomas Park, who called it quits after watching for five hours. Next they took away all oxygen, which kills a mouse in 45 seconds. The mole-rats passed out after 30 seconds but their hearts beat for the 18-minute experiment and they were back to normal once exposed to normal air again. (Those deprived for 30 minutes did not survive.) Turns out that instead of running on glucose for energy, which requires oxygen, they turn to fructose, something humans have but can't use in this way. "They have a social structure like insects, they're cold-blooded like reptiles, and now we found that they use fructose like a plant," Park says. It's possible the research could ultimately lead to methods of treating humans who are experiencing oxygen deprivation. (Could the animals help us fight cancer, too?)