Yoko the swell shark was born in a habitat of all-female sharks who hadn't seen a male in years. The aquarium has two possible explanations — and hopes to get confirmation in the coming months.

In one of the longest known cases, scientists discovered in 2015 that a female brownbanded bamboo shark at a San Francisco aquarium had stored sperm for at least 45 months — it gave birth nearly ...

Happy Presidents Day and Valentine's Day weekend! See Penguin Valentines at Cal Academy, where felt hearts line the nests of ...

In one of the longest known cases, scientists discovered in 2015 that a female brownbanded bamboo shark at a San Francisco aquarium had stored sperm for at least 45 months — it gave birth nearly ...

In one of the longest known cases, scientists discovered in 2015 that a female brownbanded bamboo shark at a San Francisco aquarium had stored sperm for at least 45 months — it gave birth nearly four ...