rationalskepticism.org

Alan B wrote:

scott1328 wrote:

Alan B wrote:And, of course, any offspring under these circumstances would always be female.

Sharks use ZW sex determination system. the shark pups were likely male.

Ah! Didn't know that.

Might not be a wise evolutionary move...

Depends on the relative importance of sexual reproduction to the shark population. In the long term, it is obviously important, but the sharks wouldn't "know" that, would they?
Also, I would like to have a more definitive answer than "the shark pups were likely male".
It is unfortunate that Alice didn't mention the gender, but IIRC, sharks only give birth to one live animal at a time - two develop initially, but the first to develop eats the other one, and then there is one!

EDIT: Ah, maybe this only applies to great whites?