20150922_R4

Source: BBC Radio 4: Today

URL: N/A

Date: 22/09/2015

Event: Beetle evolution "in this time of rapid climate change"

Credit: BBC Radio 4

People:

• Mishal Husain: Presenter, BBC Radio 4 Today programme
• Professor Rebecca Kilner: Professor of Evolutionary Biology, Cambridge University

Mishal Husain: Bad parenting creates bad future parents - a conclusion drawn not about humans but from a study of beetles, published in the journal eLife. Professor Rebecca Kilner, Professor of Evolutionary Biology at Cambridge University, led the research and she's in our Cambridge studio - good morning.

Rebecca Kilner: Good morning.

Mishal Husain: Explain the study - you were looking at burying beetles and how they look after their young.

Rebecca Kilner: That's right - so, burying beetles are unusual, for insects, because they provide care for their offspring. And in this study, we engineered two different sorts of burying beetles. So we created good parents and bad parents, and we did that simply by changing the kind of care that they received when they were larvae. So larvae that got good levels of care went on to become good parents themselves, and then they had offspring that were also good parents, but when larvae had poor care, they went on to become poor parents and they had offspring that became poor parents.

Mishal Husain: Well, what is "good levels of care" or "poor levels of care", for a burying beetle?

Rebecca Kilner: Well, it's simply to do with the amount of nutrition that they receive. So the parents, they breed on a small dead mammal, the parents will regurgitate - it's probably not ideal for breakfast time, this - the parents regurgitate small bits of dead flesh into the mouths of their larvae, and we can vary the amount that they do this, and that has substantial consequences for the rest of their offspring's lives.

Mishal Husain: So in layman's terms, is this purely then saying that this is about nurture rather than nature?

Rebecca Kilner: I suppose so - so I think the most fascinating part of this study is that we show that simply by changing the environment, we could create two different lines of behaviour, and then those very different behaviours were immediately passed on from generation to generation. And I think that's interesting, because it speaks to the nature of how evolution might work. And that's obviously important in this time of rapid climate change - to understand how world populations are going to cope with climate change, we need to understand more about how evolution works. And what our study suggests is that evolution might actually work more rapidly than was previously supposed - while the traditional view is that it involves the slow and gradual accumulation of random and beneficial genetic mutations, and what we've shown is that the environment can induce rapid inherited change in behaviour -

Mishal Husain: Rapid being in one generation, in this case.

Rebecca Kilner: Exactly, and that is passed on to the next generation, and so that could potentially increase the pace of evolution. And so that, potentially, means that under some circumstances, animals could adapt rapidly to a rapidly changing world, although we need to do much more work to identify the conditions under which this will happen.

Mishal Husain: What would you do next, to try and test your theory further?

Rebecca Kilner: Um, that's a very good question. So I think it would be good to, kind of, simulate in the lab to find out more about how adaptive, how beneficial these changes in behaviour are, and therefore the kinds of conditions in which we could see in nature these divergent behaviours evolving in the real world.

Mishal Husain: Well, because, as far as your beetles were concerned, some of them that were good parents sort of paid a price for it.

Rebecca Kilner: That's right - so the result that you've highlighted there is what we found when we brought the parents from each line back together again. So we had a good parent paired with a bad parent, and then we let them work together to raise larvae. And then, under these conditions, it was the good parent that suffered. And we think the reason was, was because it had to work hard to compensate for the -

Mishal Husain: For the other one -

Rebecca Kilner: - lower [?] level of care - exactly - provided by its partner, and it paid the price, and it died at a younger age.

Mishal Husain: Oh dear. Professor Rebecca Kilner, thanks very much.

Rebecca Kilner: Thank you.