Dr Ann Jones

They say that sex isn't a chance just to repair your faults.

It's a chance to genetically outrun threats.

So this is the Red Queen.

The Red Queen hypothesis is named after the Lewis Carroll character from Through the Looking Glass that runs and runs as hard as she can just to stay on the spot.

Amanda Gibson is an assistant professor at the University of Virginia.

Because as a clone, you're not using sex to change your DNA between generations.

So the parasites get your mark.

They know your ins and outs.

They know your every play.

running as genetically fast as you can just to stay ahead of parasites.

What snails, I hear you ask?

Just some of the most highly studied snails in evolutionary science, New Zealand mud snails.

Obviously.

And they're powerful, at least in theory, because since the 1980s, the snails have been studied by successive generations of scientists because they have some weird sex stuff going on.

The snails, not the scientists.

There are males and females, and then thousands of female-only clones of different genetic make-ups.

They're appearing all of the time, all over the place.

And having these two types of reproduction in the one environment gives the scientists perfect conditions to study some really core questions about the costs of sexual versus asexual reproduction.

Like, what is the cost of males?

One male, one female, on average, it's half-half every generation.