Why the long mantle?


Oh, and coincidentally, another ehljayer posted a link to an article about how those blue ringed octopuses copulate:

H. lunulata is a pretty (and poisonous) Asian octopus with lovely iridescent blue rings, and since the octopus has a highly developed visual system, the authors wondered if there were any interesting sexual and courtship behaviors in this species. The experiment was simple: octopuses were paired, and their behavior observed and recorded. There is little obvious sexual dimorphism here other than size and the presence of an enlarged hectocotyl arm in the male, that he uses to insert into the female mantle and deposit a spermatophore. The expectation was that the male might engage in some signalling with that arm, and that the two individuals might do something to assert their sex and negotiate before mating.

But no. These octopuses seem to be able to recognize that the other is a conspecific, but do not recognize whether the other is male or female, at least not until after they begin copulation. Put two octopuses together, and within 3-4 minutes, a male will have pounced on the other, whether it is male or female, and inserted his hectocotyl arm into it's mantle. There didn't seem to be much in the way of perceptible preliminaries.

Once copulation began, the male would figure out whether he was having sex with a male or a female. Male-male copulations typically only lasted 30 seconds and did not culminate in spermatophore release (nor did the aggressive male beg pardon of his partner), although in one instance copulation continued for 44 hours. Male-female copulations were significantly more prolonged, typically lasting over two and a half hours, and did result in release of one to four spermatophores.

Copulations always ended at the female's insistence: she would forcibly reach back with her arms and pull the male away. Furthermore, she didn't seem entirely happy with the event. Half the time, the female would actively attack the male afterwards:

In one instance, the female killed the male by pinning him down against the aquarium wall for over 10 h while cannibalizing most of his arms. This was also the male-female pair in which duration of copulation was noticeably shorter, lasting only 25 min.

(Reply to this) (Thread)

Verrry interesting, quite similar to my own procedure.

(Reply to this) (Parent) (Thread)

I'm quite fascinated. Hopefully one of your partners doesn't end up cannibalising your limbs. That would like totally suck.

(Reply to this) (Parent) (Thread)

Not if I eat their head first.

Wait...

Edited at 2008-04-20 07:42 am (UTC)

(Reply to this) (Parent) (Thread)

NOM, NOM, NOM!

(Reply to this) (Parent) (Thread)

Indeed, I can see your blog is so not worksafe! Darn cephalopods!


Something about design of the swirling things in head on this one vaguely reminds me of diagrams of the reproductive tract.

(Reply to this) (Thread)

It's vaguely fallopian and therefore unsuitable for minors!

(Reply to this) (Parent) (Thread)

He looks like one of the aliens from the Star Trek episode(s) The Cage/The Menagerie.

(Reply to this) (Thread)

I shall have to go a-looking!

(Reply to this) (Parent) (Thread)

How about the famed blue ringed octopus of your region?

And, being an Aussie, maybe a few sharks? They must be interesting characters worthy of a series.

(Reply to this) (Thread)

I'd do seahorses before sharks. Sharks are weird in ways that aren't as compelling to me - like being able to throw their jaws out to catch prey and that their skin when rubbed against the grain is as abrasive as the teeth of a saw. The hammerhead is cool though.

(Reply to this) (Parent) (Thread)

They're bizarre. I'm imagining funny cartoon sharks, not the kind that bite your leg and have you bleed to death through your femoral artery. Happened to a scientist not so long ago swimming her daily laps in central California.

(Reply to this) (Parent) (Thread)

Dat's peerty.

(Reply to this) (Thread)

Thanks Jess! Your icon is completely mesmerising.

(Reply to this) (Parent) (Thread)

Kyooooooooooot. I wants ta hug him, and kiss him, and make him my bestest friennd. Then I can die from his neurotoxin, like the people who play with those blue ring octopussies.

(Reply to this) (Thread)

Haha! And septicemia from being viciously beaked.

(Reply to this) (Parent) (Thread)

Ow. The cute burns us.

:D I think he's my favorite so far.

(Reply to this) (Thread)

cutecutecuteycutecute!

(Reply to this) (Thread)

...plus he can kill you with his brain.

(Reply to this) (Thread)

*hands a cephalopod cookie*

...it looked at me with his big, pretty eyes... and I couldn't say no... 83

(Reply to this) (Thread)

i want to pet its fallopian braintubes! ♥

(Reply to this) (Thread)

Mwahahaha!!!!! World domination by cuteness! :) I love the glowing effect you got. I got a wacom pad here recently and am still plodding slowly at learning to get decent art via computer..lol...slow but sure I'll learn the ins and outs of it. Your work is awesome.

(Reply to this) (Thread)

This one is particularly cute. :) I've been collecting them all.

(Reply to this) (Thread)