White-bellied pangolins have second-highest number of chromosomes among mammals

[Still Waters]

There's a lot scientists don't know about the pangolin—a peculiar, scaly mammal that looks like a cross between an aardvark and an armadillo. Now, a new paper published in the journal Chromosome Research reveals what UCLA researcher Jen Tinsman calls a "scientific surprise" that underscores how unusual the animal is.

The scientists discovered that the female white-bellied pangolin has 114 chromosomes, more than any mammal except the Bolivian bamboo rat, which has 118—and far more than humans, who have 46. Other pangolin species have more typical numbers of chromosomes, ranging from 36 to 42.

The scientists also identified another genetic quirk. Male white-bellied pangolins have a different number of chromosomes, 113, than their female counterparts; in most species, males and females have the same number.

"There's nothing else like them on the planet; they're in their own order, their own family," said Tinsman, a UCLA research fellow and co-author of the study, adding that pangolins' closest relatives include cats and rhinoceroses.

https://phys.org/news/2023-05-white-bellied-pangolins-second-highest-chromosomes-mammals.html