This is scientific American 60 Second Science. I'm Annie Sneed.

When humans take the drug MDMA best known as ecstasy,

they feel a deeper connection to others, emotionally and physically, because

MDMA affects serotonin, a nervous system chemical.

Serotonin is, you know, one of the oldest neurotransmitters.

Gool Dolan, an assistant professor of neuroscience at Johns Hopkins University who studies

social behaviors.

It's been implicated of all kinds of functions, lots of them having nothing to do with

social.

And so we wanted to know, well, how long ago was serotonin's function, you know, really about encoding social behaviors.

So Dolan and her colleague did what any scientist would do.

They gave MDMA to octopuses.

Octopuses are aes social creatures and their last common ancestor with us

lived more than a half billion years ago, which made them a good test subject for the question

at hand. The researchers set up a simple test.

We have a large chamber, which is basically an aquarium, tank, and then we divided into three chambers.

And on one side, we put a little overturned flower pot that's

clear and plastic and has lots of holes in it and underneath that overturned pot we

have a toy object and on the other side we have that overturned orchid pot, but this one has an octopus in it.

The researchers put an octopus in the middle chamber and watched it swim around for 30 minutes.

They measured how much it interacted with one side of the chamber, the one with the other octopus,

versus the chamber with the toy.

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