When Aretha Franklin and Annie Lennox said “sisters are doin’ it for themselves,” perhaps they were imagining two female eagle rays at a New Zealand aquarium getting pregnant without needing a male eagle ray.

Two whai repo, or eagle rays, Nibble and Spot, at Kelly Tarlton’s aquarium in Auckland became pregnant despite there being no male ray in their tank for two years. Then, like two best friends who vowed that their children would also become best friends, they gave birth to eleven pups at the same time on New Year’s Eve. How these births happened remains a mystery for the team at the aquarium.

Yes, Nibble and Spot may be hiding clandestine eagle ray dick appointments from the aquarium’s workers, but another possibility is that they became pregnant through a process called parthenogenesis. This is a rare form of reproduction where an embryo develops without fertilisation by a sperm.

Another theory is that the sperm came from a male eagle ray that was in the tank two years ago.

“Nibble and Spot could have stored sperm inside their bodies for the last two years. Sperm storage has been recorded in several shark and ray species, so we think this is the more likely scenario,” says Andrew Christie, a curator at Kelly Tarlton’s.

These are all hypotheses at this stage and the aquarium plans to conduct research on the rays’ mystery pregnancies to find a conclusive answer. Until then, we can hold onto the belief that Nibble and Spot have sussed that men are not necessary for the continuation of their species.