Eleanor Drinkwater: amazing insects

Beetle enthusiast doing research on woodlice personalities, Eleanor Drinkwater told Chris Smith about the wonderful world of insects...

Chris - So Eleanor, we had a quiz on the Naked Scientists the other day and one of the questions was that "all the spiders on Earth could eat all the humans on Earth in a year" (true or false). Do you know what the answer was?

Eleanor - No, I don't, but I would love to know that.

Chris - Who thinks it's true? Hands up. A handful of people. Actually it's true! Because if you work out how many hundreds of millions of spiders there are and how much the spider eats, when you scale that to the population of spiders on Earth, they would actually easily devour all 7.7 billion humans in under a year.

Eleanor - But the question is would they want to, because a fly or something like that to many spiders be very tasty. But take a look at a human, we're gusting in comparison.

Chris - So you're saying, human vs blue bottle, you'd rather eat a blue bottle?

Eleanor - If I was a spider!

Chris - Where I was going with this, is that there are extraordinary numbers when we actually add up the scale of the insect world, of the microscopic world. It's enormous in terms of the numbers, isn't it?

Eleanor - Yeah, I absolutely love thinking about it. So, so for example, insects alone, this is not including anybody like snails or anything like that, just insects alone. We know about 1 million species on the planet, but actually estimates put the actual number of species at about 10 million. So just the number of un-described species is absolutely phenomenal. And that's species. If you got a giant set of weighing scales and you put all of the insects - again, just insects, no snails or anything like that. Just insects - on one side of the weighing scales and all the people on the other side of the weighing scales, the insects would probably weigh about 70 times the amount of people, which is just wonderful to think about.

Ljiljana - We are still learning so much from insects. For example, there is a new type of colours that we make, new types of kind of dye like materials that were inspired by butterflies and the way how they create their own colours. Or spiders. We are working now also in my lab a little bit with materials which are inspired by silk that spiders make. So they make an amazing number of chemicals and structures that we are really learning about them now.

Eleanor - And the thing that I find phenomenal is the fact that we just know so little about so many, even all the really big charismatic species like you know, my favorite beetle is, is the Titan beetle, biggest beetle on the planet. No one has ever seen it's larvae.

Chris - How big is it?

Eleanor - So it grows to about 17 centimeters. And the crazy crazy thing is that yeah, that's big, but baby beetles are bigger than the adult beetles.

David - How do they give birth then?

Eleanor - That would be cool to see. But no, no, no. They lay an egg. The life cycles are just remarkable. So taking something like the Titan beetle, would probably have the case that the eggs are laid, and it will grow into a larvae and then it will stay as a larvae in the soil, in the rotting rotting wood for like perhaps five to 10 years as a larvae, but for emerging into an adult, in which its adult lifespan is perhaps maybe two or three weeks. Just remarkable that they've evolved this really wonderful life cycle.

Chris - I remember going to New Zealand to Waitomo, which I think is a wonder of the world really, the modern world. I don't know if you've been there, but it's the glow worm caves there and there are so many glow worms in this cave that you can read under the light that they produce. It's really stunning and I interviewed one of the people who was taking us round on this tour and he said, it's a pretty miserable life if you're a glow worm though, because you live in the roof of this cave and you produce this light and dangle down your fishing line, thread to catch insects and things which you then eat and devour, your sole aim being to get big enough to then turn into a fly, which doesn't actually have a mouth. So you're born and you live as long as you can survive with the energy you've already packed in, in order to just find a mate, mate and die!

David - But you don't have to take her out for a meal before you get what you want.

Chris - David, I can see you're clearly a romantic. When's your next anniversary?

Chris - What about intelligence in insects though? Because we think of ourselves, we have this very, very kind of superlative view of ourselves, and we think we're the pinnacle of intelligence and things. Are insects, particularly clever?

Eleanor - There is so much more going on in invertebrate cognition than perhaps many people are aware of. I always feel like we're just beginning to scratch the surface of what many species are capable of. So taking, for example, bees, there's always so many lovely experiments done on bees. There was this absolutely lovely experiment that was done showing that you can train bees to tell the difference between paintings done by Monet and paintings done Picasso. And if that's not a like higher cognitive ability, I don't know what is!

Chris - Which do they prefer?

Eleanor - Ah, I don't think they went that far! Or wasps. They can tell the difference between individuals by their different facial markings. Again, bumblebees. There was another lovely experiment done in which they essentially trained them how to play golf, which was just a great experiment. They, they trained them to push a little ball to go down a hole and then they get treated. They got it and they're very capable of, of learning.

Chris - I remember reading that because that was done at Queen Mary University of London. We talked to them about that and they said, not only could you train a bee, but a bee will train another bee. So the bees will watch the first one do it and then they can copy, so they can play golf and waste their life away too. Questions? This one came in from Stephanie. Stephanie says, "I read that an endangered komodo dragon can give birth without a male. If so, how?"

Eleanor - Wow, that is a very good question. I don't know anything about komodo dragons, but I do know something about snails. This is relevant, I promise! So snails like Shellock Holmes here, is both simultaneously male and female. So has the ability when they can't find a mate self-fertilise themselves with their own sperm. So I know that's what snails do. Do you know how komodo dragons do it? Is it the same?

Chris - Yeah, it was 2006 and it was actually London zoo and they had a komodo dragon that was female and they were most surprised when they got another komodo dragon from one single female komodo dragon. This is a process called parthenogenesis. And unlike humans, when we have sex and you mix eggs and sperm, if you have an X chromosome and a Y chromosome, you get a man. If you have an X and an X, so an X sperm and an X egg, you get a female. Now with komodo dragons, there's actually three different combinations of genes they can have, but we'll leave that to one side for one moment. It suffices to say if you have the equivalent of two X chromosomes in a komodo dragon, you are male. If you have two different chromosomes, you are female. So if you have a female komodo dragon that say washes up on a beach and it's one female on its own, it's going to have two different chromosomes, but because it's got the ability to then make an egg, which has only got one of them in it, that egg can then turn into by, copying the chromosomes, one that's got two sets of the same type of chromosome X, X and so it has a male baby. And that means you've then introduced into a population of what would be exclusively females a male and they can then reproduce sexually again, and introduce genetic diversity. So yes, that's how they do it Stephanie.