Testing the Frog Glue

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You're listening to Strange by Nature, your guide to the strange, weird, unbelievable and improbable wonders of the natural world.

**Kirk Mona** (0:52)
Hello, everyone, and thanks for being here today. I'm Kirk Mona, and joining me are Rachel Gimza and Victoria Thompson. We're all naturalists who together have scoured the world for weird and wonderful wonders, just to please your mammalian brain's desire for novelty. Isn't that nice? Let's do this.

**Victoria Thompson** (1:12)
Well, hey everybody, welcome to the show. Good to see you guys.

**Rachel Gimza** (1:15)
Good to see you too.

**Kirk Mona** (1:16)
Hey, good to be here.

**Rachel Gimza** (1:18)
Love it.

**Victoria Thompson** (1:19)
I am starting things off this week. And obviously, you two are still working as naturalists. I'm not, I don't know about other states, but... In your heart, you are. Yeah, in my heart, I am. Pretty much every nature center in Minnesota has a collection of reptiles and amphibians. Our ambassador animals, right?

**Kirk Mona** (1:39)
Right, yeah.

**Victoria Thompson** (1:40)
And their terrariums give visitors something fun to look at. But also many of the animals are used in educational programs. It's a really great way to engage kids and teach about different types of animals and their different adaptations and stuff.

**Kirk Mona** (1:54)
Absolutely, yeah.

**Victoria Thompson** (1:55)
And as you guys know, one of the most common animals that we use is the American toad. Oh, yes. For a few reasons. That's right. They're easy to take care of, for one. They're pretty robust. Yeah, pretty robust for an amphibian. Like, they can tolerate being touched by a bunch of kids. And unlike some other types of frogs, they are pretty slow. They don't jump very high, so they're not going to escape super easily when you have them out on the floor.

**Kirk Mona** (2:25)
Yeah.

**Victoria Thompson** (2:27)
In addition, they have a lot of cool defenses that you can talk about. Because frogs and toads in general seem very vulnerable to predators. They don't have thick skin, scales, teeth, claws, any of that. Yeah.

**Kirk Mona** (2:41)
Right. Right.

**Victoria Thompson** (2:43)
So we get to talk about some of the cool things that the toad can do. It's got that bumpy brown skin that's great for camouflage with the forest floor. They can puff themselves up with air to make themselves both bigger and more intimidating and also more difficult to swallow for predators. They can also play dead since many predators only try to attack moving prey. And then there are those two bigger bumps on the back of their head, the parotid glands that secrete a horrible tasting bitter poison that means most predators will only try to mess with a toad once. And of course, what almost anyone who has ever picked up a wild toad will have experienced, which is that they pee on you.

**Kirk Mona** (3:27)
Yeah they will.

**Rachel Gimza** (3:27)
I was waiting for you to mention that one.

**Victoria Thompson** (3:32)
And you know, that's a lot for one species of toad. Of course, other species of frogs have other defenses. Poison dart frogs are famous, of course, for their bright colors and deadly poisonous skins. And even non-poison dart species, there are many species of frogs that have come some kind of toxicity on the outside of their body and their bucus to deter predators. More recently, I learned that there are several species of frog that can admit a very loud yell when they are threatened or surprised.
Which might be enough to startle a predator into dropping them. You can see some videos on YouTube. The main thing I want to talk about today, though, is an unusual defense that a few species of frog have developed, which is glue.

**Rachel Gimza** (4:25)
What?

**Kirk Mona** (4:26)
Frog glue.

**Rachel Gimza** (4:28)
Frog glue? I've not heard of this. What? Frog glue.

**Victoria Thompson** (4:32)
Yeah, a number of otherwise relatively unremarkable frogs and toads all can, when threatened, to create a special white fluid from their backs that quickly becomes incredibly sticky. So field researchers that handle these frogs, like their fingers get stuck together, their fingers get stuck to their flashlight, their notebooks, anything they try to handle.