Excuse me, dear, which octopus are you?

Male blue-ringed octopuses seem to get pretty far along in courtship before they know for sure whether they’ve found a genuine female, report California researchers.

Males reached out and touched another male as readily as a female, say Mary W. Cheng and Roy L. Caldwell of the University of California, Berkeley. In the July Animal Behaviour, the researchers discuss 15 close encounters between male octopuses and 9 between a male and a female.

Watching the Australian species Hapalochlaena lunulata in a lab revealed no apparent differences between male octopuses approaching another male and those flirting with a female.

Whatever the target’s gender, a male octopus placed its specialized sperm-transfer appendage, the hectocotylus, into the main body cavity of the other octopus.

Then things changed. The initiating male released a sperm package only into females.

Contact time differed, as well. A male stayed in position with a female for about 160 minutes—at which point she ended the contact, often with force. A male that had reached into another male, however, withdrew in about 30 seconds, no force required.

Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.

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