The punk rock life of cephalopods

Flora Lichtman (0:02)

Hey, it's Flora, and you're listening to Science Friday.

In case you missed the memo, it is Cephalopod Week, the most wonderful time of the year. And if you're a long-time listener or just an ocean nerd, you might be thinking, oh, that's cute, but how much more is there really to learn about squid, octopus and cuttlefish? Well, strap in, because I think this conversation is going to blow you right out of the water.

These soft-bodied creatures, it turns out they have a hard edge. Have you heard of octopus death spirals? Cephalopod cannibalism? Here to take us into the deep end are two Cephsperts, Heather Judkins, who's a marine ecologist and taxonomist at the University of South Florida, and neuroethologist Yan Wang, who studies the brains and behaviors of Cephalopods at the University of Washington, Seattle. Thank you both for being here.

Heather Judkins (1:00)

Thanks for having us.

Yan Wang (1:01)

Thanks so much for having us.

Flora Lichtman (1:02)

Happy Cephalopod Week.

Yan Wang (1:04)

Thanks.

Flora Lichtman (1:04)

Do you celebrate?

Yan Wang (1:06)

What's funny this year is that our lab is actually getting a shipment of octopuses on Thursday, so that'll be really exciting.

Flora Lichtman (1:14)

On World Octopus Day.

Yan Wang (1:16)

Exactly.

Flora Lichtman (1:16)

The very day this podcast comes out, the day before this goes on broadcast. How do you even get a shipment of octopuses? What does that look like?

Yan Wang (1:25)

Different labs, different researchers do it different ways.

Here in Washington, we work with a collector who's out in California, because that's where the species of octopus that we study lives. He is able to get octopuses for us by diving for them, and then they get shipped overnight FedEx in their dens, and we're there waiting for them bright and early in the morning to acclimate them to our system.

Flora Lichtman (1:52)

They get shipped FedEx.

What does it look like when you open the package? Is it like an aquarium, like a Tupperware? What should I picture?

Yan Wang (2:00)

Yeah, they come in double plastic baggies, essentially.

And yeah, they've got lots of water in there. They've got their homes, plenty of oxygen. Yeah, so they come in a big styrofoam box, and then kind of like an aquarium baggie.

Flora Lichtman (2:21)

Wow, okay.

We have to talk about death spirals right off the bat. This is something you study, Yan, right?

Yan Wang (2:28)

Yeah, that's right.

Flora Lichtman (2:29)

What is it? What's an octopus death spiral?

Yan Wang (2:32)

Yeah, so for the majority of octopus species that we know about on this earth, something really unique happens after they mate and reproduce, which is that they undergo these really dramatic behavioral changes that always ultimately lead to their death. And these changes are really striking from how they normally would behave. So octopuses are really voracious predators. During this time, they stop eating. The females are primarily taking care of their eggs.

As they get closer and closer to death, these females will abandon their eggs often, or spend a lot of time outside of their pot. They will eat their arm tips, they will rip skin off of their mantles.

Oftentimes, they engage in behaviors that will rub the skin or damage their skin on their body. And all of this inevitably leads to their death. And while other animals also die after reproduction, this is a process called semiparity. What's really unique about octopuses is that it's a part of their nervous system that controls this and it appears to be reversible. So if that part of the brain is not functioning, then these behaviors and this death spiral doesn't happen.

SPEAKER_5 (3:54)

Wow.

Flora Lichtman (3:55)

Why would this be the way they meet their end?

Yan Wang (3:58)

I think why questions are really, they're so interesting because you can kind of tug at them forever.

So I don't have an answer to why because it can be really hard to test and falsify why questions. But I'll say this. One thing we know about is that cephalopods are highly, highly cannibalistic. So for example, young octopus hatchlings will, if they're close to each other, will often cannibalize each other. And so researchers in the 70s have put forth this idea that this is a very effective means of population control to ensure that the previous generation dies off and that their offspring are able to grow up and survive.

Flora Lichtman (4:47)

This is really changing my perspective on cephalopods. Like I think of them as like majestic and I don't know. This is very punk rock. Related to Living Hard and Dying Young, we got this question from a listener.