Things that go 'bonk' in the night: Bisexual deep-sea squid can't tell who's who in the murky depths


Love is blind: A female Octopoteuthis deletron is pictured. White dots on the dorsal arms show spermatangia is present on this squid

Male deep-sea squid end up mating with members of their own sex as they cannot see properly in the murky depths of the ocean, scientists believe.

Researchers discovered the mishap using a remote-controlled submarine in the Monterey canyon off California.

Their footage showed males belonging to the squid species Octopoteuthis deletron struggled to distinguish between potential mates and members of the same sex 800 metres down in the dimly lit Pacific.

Fun in the dark: The Octopoteuthis deletron struggle to distinguish between potential mates and members of the same sex

However, instead of evolving over the years to work out which squid are females, scientists found males adopt a strategy of mating with any deep sea squid they come across.

This is because some squid can drift for a lifetime under the sea without ever bumping into a potential sex-partner, experts believe.

Researchers said in a study published in the journal Biology Letters that males: 'routinely and indiscriminately mates with both males and females.'

Calling it 'a shot in the dark', the team realised the cost involved in wasting sperm on another male were probably smaller than the costs of developing courtship or the ability to discriminate between sexes.

In the study, they wrote: 'In the deep, dark habitat where O. deletron lives, potential mates are few and far between.'

During opposite-sex mating, males use a long tentacle-like appendage - a penis of sorts - to deposit small sperm-laden sacs, called spermatangia, onto females.

source: dailymail