Dr. Poppy Crum

So they've evolved very interesting systems to be able to achieve what they needed to, which one,

If you ever see marmosets, they're very stoic, unlike macaque monkeys that often have a lot of visual expression of how they're feeling.

Marmosets always look about the same.

But their vocalizations are almost like birdsong, and they're very rich in the information that they're communicating.

They also have a pheromonal system.

Like, you know, you can have a dominant female in the colony who may not be – because you have to have ways of – when one sense is compromised, the other senses sort of rise up to help assure that the success of what that species or system needs is going to be – you know, thrive.

Right.

And in the case of marmosets, you can have the dominant female effectively causes the ovulation of like the biology to change of all the other females.

And you can have a female that you put just in the same proximity, but now as part of a different group.

group and her biology will change.

I mean, it's very powerful, the pheromonal interactions that happen because those are things that can travel even when I can't see you.

One thing when I was working with them that I thought was, and I never, I like writing pads more than publishing papers.

But these things are real because I was studying pupillometry is understanding the power of their saccades.

I could know what they were hearing based on their eye movements.

So if I play – marmosets have – some of their calls are really antiphonal.

They're to see, hey, are you out there?

Am I alone?

Who else is around?

Yeah, and sometimes it's light or sometimes it might be like, oh, from –

Be careful.