This is But Why a podcast podcast for Curious Kids from Vermont Public.

I'm Jane Linton.

On this show, we take questions from curious kids just like you and we find answers.

In making today's episode, I learned a lot, and I had my mind kind of changed. So I want to know at the end of the

episode, if you experience the same thing, let me know. Have you ever heard the word parasite?

A parasite is by definition bad. At least it's bad for its host. A parasite is a living organism that

uses a different organism. It either lives in or on this other organism called the host,

and the parasite uses its host to gain food or be able to reproduce in a way that's bad for the host.

Basically, the parasite thrives at the expense of the host.

Sounds bad, right? And it can be really bad.

Sometimes parasites make their hosts too weak to eat.

Sometimes they even kill their hosts. And sometimes humans can be the hosts to parasites. There's a lot of medicine designed to help us fight off and get rid of parasites. Of course, parasites aren't always super dangerous. Sometimes they're just really annoying and itchy, like head lice. But still,

I would say that those head lice are still thriving at our expense, right? But our special

guest today loves parasites. She says they're fascinating and often very beautiful.

And she says they're really important, even good for our planet.

She says without parasites, our ecosystems would fall apart.

So without further ado, let's meet this scientist and see if she can convince you to at least appreciate, if not love, the world of parasites.

I'm Chelsea Wood. I'm an associate professor in the School of Aquatic and Fishery Sciences at the University of Washington.

But I prefer to be known as a parasite ecologist because parasites are my favorite things.

What does that mean exactly?

Well, an ecologist is a person who studies living things, organisms, where they occur in the world and why.

And a parasite ecologist is someone who studies that question, but for parasites.

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