MADELEINE BRAND, host:
Hey ladies, ever felt your date was more octopus than men, arms everywhere? Well, female octopuses maybe they feel your pain. A new UC Berkley on octopus mating habits has some surprising findings. Christine Huffard is the lead author of that study. She observed the octopuses' behavior firsthand while conducting research in Indonesia. And she joins us now from the Monterey Bay Aquarium Research Institute. Thanks for joining us.
Dr. CHRISTINE HUFFARD (Lead Author, UC Berkeley Study; Postdoctoral Fellow, Monterey Bay Aquarium Research Institute): Thank you for having me.
BRAND: Well, I'll tell you what piqued our interest. We read the press release that UC Berkeley sent out, and in the first paragraph it said that your research found at least one species of octopus, quote, "engages in such sophisticated lovemaking tactics as flirting, passionate hand-holding and keeping rivals at arms length." Now, what did you observe?
Dr. HUFFARD: Flirting really is - it's a type of courtship. The hand-holding is definitely a bit of a stretch, but it does look like it, because when we look at the two individuals mating, we can see that there's one big long arm stretched in between them, and that looks like they might be holding hands.
But what that actually is is the male's specialized mating arm. One of his eight arms has a groove along the back that's used to pass sperm packets from his body to the female. And so, by little waves of muscle action, almost like peristalsis in our guts, the little sperm packets are passed from the base of the arm all the way to the tip into the female.
BRAND: Now, you also observed male octopuses exhibiting what we might like to call "macho" behavior.
Dr. HUFFARD: Oh, yeah. There's no doubt that males fight over females. They fight very intensely. We saw them strangling each other - so, actually cutting off the flow of water over each others' gills. We saw them wrestling to the ground and rolling around on the bottom of the sea floor.
These octopuses actually are able to drop their arms off the way a lizard does its tail. And what we found most surprising was that males have to - they have a trade-off. They can either be really choosy and find something that's really valuable and stick with it and keep at it, or they can spend their time actually looking for lots and lots of mates. So, these males...
BRAND: So, it's like being monogamous or playing the field?
Dr. HUFFARD: Right. They will definitely spend most of their time with a big female. Once they find her, they'll stay with her as long as they can, and they don't go out seeking other females. But if smaller females happen to come across their path, they certainly don't turn down the chance to mate.
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BRAND: They're not stupid after all.
Dr. HUFFARD: But really - exactly.
BRAND: What I also was interested in, in reading about your study, were these so-called "sneaker males." They moved in on unsuspecting conquests by masquerading as females.
Dr. HUFFARD: It seems that these octopuses are able to tell each other's sex, so, whether they're male or female, by the color patterns that they're showing. So, the sneaker males, in order to mate, they actually showed the more female-typical color, so, the more camouflaged coloring, rather than showing off the male-typical coloring.
And that allowed them to mate with females right in front of the males. But they also did other behaviors like hiding behind rocks and waiting for the big male to go away, and they were really just avoiding an aggression any way they could...
BRAND: Didn't want to lose an arm over it.
Dr. HUFFARD: Exactly.
(Soundbite of laughter)
BRAND: Yeah. Why is this so surprising? Because a lot of animals exhibit these aggressive tendencies when it comes to mating. What were you surprised by when you observed the octopuses?
Dr. HUFFARD: So many different animals fight over mates, but we were not expecting to see them in octopuses. People had generally thought that octopuses were solitary, and then after mating, it was just assumed that they went about their daily lives separately. It was also assumed that males didn't compete for females and this really just turned those ideas upside down.
BRAND: Christine Huffard, Thanks for joining us.
Dr. HUFFARD: Thank you so much.
BRAND: That's Christine Huffard. She studies the mating habits of octopuses at the Monterey Bay Aquarium Research Institute and she joined us from member station KAZU in Monterey, California.
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BRAND: There's more to come on Day to Day.