Japanesse snakes and toads

snakes and toads.m...

So what's this story about snakes that are robbing toads of their toxins?

Mark - Most animals tend to steer clear of poisonous toads, but scientists have found that there's a species of Japanese snake, the Japanese colubrid snake, that actually seeks out toads because it wants to eat them. This is so it can steal their toxins and use them to kill its prey.

Chris - But why doesn't the snake end up succumbing to the toxin?

Mark - Well that's the interesting thing. Now that the scientists involved have actually found out that it's able to do this, they hope now that they're going to be able to work out why it does this. What they did was analyse two different groups of snake. One of them was fed on these toads and the other one didn't have the toads in its diet. They found that it was only the ones that were able to eat toads that ended up being poisonous.

Chris - So it's not a genetic difference, it's purely a dietary difference.

Mark - That's right. There's a small island off Japan where these snakes don't have access to toads, and they found that if they took snakes from that island and gave them toads, they ultimately became poisonous after a relatively short time. When they looked at exactly what molecules the snake was using, they found that they'd actually changed the molecule slightly. So they'd taken them in in one form from the toads and tweaked them chemically. Now that, the scientists speculate, might be the reason why the snake isn't poisoned by the toads because it can rapidly change their chemistry to stop it doing them damage.