Dr. Sinead English

Hi, I'm Sinead English, and I'm a future leaders fellow and a associate professor at the University of Bristol in the UK.

Baby on board, that kind of thing.

So they're the Diploptera punctata, and they're known as the Pacific beetle mimic cockroach.

You know, they don't look like cockroaches that might scuttle across the floor.

They're quite pretty, like they have this beetle-like carapace on their back.

But of all the cockroach species, they're the only ones which are pregnant.

So they're the only truly viviparous cockroaches.

It's more common in flies compared to cockroaches.

It could be that there might be particularly high predation against that early life stage and then kind of keeping them inside until they're a bit more developed.

And then they come out a little bit less vulnerable to those predators, helps increase the general evolutionary success of that species.

But it comes at a big cost because you can't do that for 100 nymphs.

So then you have to kind of put a little bit more in investing and fewer that come out even more protected.

Mm-hmm.

I think that actually that resource uncertainty aspect is really interesting because that's one of the evolutionary reasons why they think lactation has evolved in mammals.

And I think just to follow on, a really interesting aspect of that is this link between pregnancy and lactation and when they occur.

So in a lot of the insects, they're producing this milk, but it's during pregnancy.

So it's a bit different to the way we have it in mammals where you have

the nourishing that happens in utero, and then you have lactation afterwards.

I think that's a really amazing thing about cockroaches is that they manage to make quite a lot from not very much.

So, you know, they don't feed anything particularly nutritious.