Octopoteuthis is a curious animal. As the name suggests, it's a squid that looks like an octopus. Babies have eight arms and two tentacles, but they lose the tentacles as they grow up--becoming the only adult squid with eight appendages.
They have other intriguing features as well. We tend to think of squid as relatively sociable animals traveling in schools or shoals, but Octopoteuthis lives a solitary life in the deep sea, rarely coming across another member of the same species.
Which brings us to this very cool study. Henk-Jan Hoving (with whom I have had the pleasure to drink lemonade and geek out about cephalopods) and his colleagues found that males of Octopoteuthis deletron hedge their bets by mating with any conspecific* they find--male or female. Scandalous!
It's not the first time male squid have been known to deposit sperm with other male squid--I've even seen it in our gregarious friend the Humboldt squid. But it's rare. In O. deletron mating is truly indiscriminate--the authors found sperm in equal proportions in males and females.
When you think about it, it's not too surprising. I certainly can't tell the sexes apart in most species of squid; why should I expect them to be able to? Anyway, sperm is cheap--better to err on the side of accidentally inseminating a male than to miss your chance to inseminate a female. Especially when deep-sea encounters are few and far between.
But once you start thinking along these lines, you have to wonder--just how indiscriminate are they? Would a male O. deletron mate with any old squid he came across, even if it isn't the same species? After all, inseminating a member of a different species (male or female) is no more of a dead end than inseminating a male of the same species. And telling the different between species may be just as much effort as telling the difference between genders. So, I wonder . . .
* I really wrestled with this sentence! Conspecific is horrid biological jargon, and I rebelled against using it, but it's just so much more succinct than "member of the same species." Eventually I weakened, and left it in. Forgive me.
Squid Seeking Squid, Any Sex . . . Or Species?