Erectile Tissue Found in Octopus 'Fingers'

Researchers said on Wednesday they had found erectile tissue in the tentacle of a male octopus, the first time such tissue has been seen in an invertebrate. [...] Thompson, who called the finding weird, said biologists have looked for erectile tissue in other mollusks but not found them. "It is not surprising that no one has noticed this before," Thompson said. [...]

Observing their mating is difficult and often the females attack and eat the males during courtship. In fact, it was while watching a female turn on a male who was attempting to mate with her that Voight made the discovery. The male hurriedly withdrew his tentacle -- "because the female was probably eyeing him up as lunch," Thompson said. [...]

"We haven't gotten a male octopus to perform for us, as it were, in the lab," Thompson admitted. [...] "Erectile tissue might be a way to have a large copulatory organ when it is in use," Thompson said. When not in use, it would be small and out of the way.

"Running around with an erection potentially could be difficult."