NARRATOR: I wanna introduce you to two fascinating individuals.

This is Kelly Brenner, a writer from Seattle.

They can pop up anywhere, almost overnight.

NARRATOR: And this is Crow Vecchio, a volunteer ranger at Mount Rainier National Park.

CROW: Never overlook any piece of rotting wood.

NARRATOR: They're not formally accredited scientists, but rather naturalists in the classic sense.

Nope, nothing there.

NARRATOR: Their curiosity of the natural world inspires them to explore, observe, record, and share their findings.

Nope, nobody home.

[quirky music] NARRATOR: And though they work individually and have never met, they are on a similar hunt.

KELLY: I think that is just fungus.

NARRATOR: They share a common obsession.

CROW: What have we got here?

for an obscure and overlooked organism.

This is good.

CROW: Oh yeah, there we go.

NARRATOR: Slime mold.

[footsteps thudding] KELLY: People walk past me on the trail and they just, once they see the camera, they mostly ignore me.

[laughs] Hi!

Hello.

Most of the time when I'm in the forest and somebody says, "What are you doing?

Looking for mushrooms?"

I'm like, "No, I'm looking for slime molds."

"Okay, bye."

[laughs] PASSERBY: What are you filming?

Slime molds.

PASSERBY: Okay.

[laughs] Nobody ever stops to ask what's a slime mold.

I don't know why.

Anytime I'm out in the woods, I have my eye tuned to looking for a slime mold.

[quirky music] NARRATOR: Anyone who has hiked in the Northwest has seen a slime mold, but likely didn't know what they were looking at.

Some look like tiny balls of fungus on rotting logs, or strange patches of gooey orange globs.

Some look like fuzzy white mold, and some are a slimy, bright yellow blob, descriptively nicknamed dog vomit.

Everybody should go hunting for dog vomit.

Slime molds have a PR problem because for one, they're called slime molds and that's not appealing and it's not representative of how beautiful they really are.

[inquisitive music] The sporangia, the fruiting bodies, are absolutely gorgeous.

Just gorgeous.

I mean, they are so stunningly beautiful.

There's iridescent.

There's like the cotton candy pink ones.

There's some that look like champagne flutes with fireworks in them.

But you look closer and closer and closer, and the closer you get, the more it reveals and the more spectacular they are.

Okay, with the hand lens, you can actually observe the openings in the tips of the tubes, which is where they emit the spores.

KELLY: The orbs on this one, on the top of these skinny stalks, a lot of them nod like they're tired.

NARRATOR: Slime molds are decomposers of the forest.

Often found on rotting logs, they're commonly mistaken for fungus.

It's interesting to note that slime molds were originally believed to be fungal, but they do things that fungi don't do.

They move.

NARRATOR: When we learned that slime molds move, we had to see this for ourselves.

[intriguing music] We ordered a smile mold kit online and set up our cameras for a time-lapse.

The yellow is a sample of living slime molds.

Next to them are oats, one of their favorite foods.

When one of them finds a tasty little bit of bacteria, it sends out a chemical signal and others of its kind that are in the area, they congregate, and they consume whatever that food source is.

Somehow, without a brain, they can contract or expand the cell membrane so that it forces the cytoplasm forward or in retreat.

Somehow that action gets coded into their genetics so that they can actually remember where a food source is.

They can also remember what time they were fed in the lab.

If you feed them, say, at 2:00 in the afternoon, give them an oat, keep doing this for two weeks, then one day don't give them an oat at 2:00, guess what?

They're going to still show up because they're expecting their lunch.

And that's for real.

How can it do that without a brain?

Just looking with a bare eye, they might all look the same.

But once you look under the microscope, it really reveals a lot of differences.

And this is also the best way to learn to identify the species, because some of them are so similar that the only way to distinguish them is by looking at their spores.

It's a microscopic time.

It's like a whole different world.

I leave this world behind, and living in that little tiny world, it's like going to another universe.

[laughs] [quirky music] NARRATOR: More than 900 species of slime molds have been discovered.

They can be found all over the earth, including deserts and in the Arctic.

They are one of the planet's oldest living organisms, dating back to the time of the dinosaurs.

They first appeared in scientific literature in the 1700s, yet 300 years later, very little is known about them.

And very few people study them.

KELLY: Locally, I don't know hardly anybody who, you know, goes out looking for slime mold.

So it's not like I have a friend I can call up, "Hey, let's go on a slime mold date."

NARRATOR: When Kelly wanted to learn more about slime molds, she searched for a collection in an herbarium.

The closest that she could find was in Canada, so she started a collection of her own.

[quirky music] I'm here in the Northwest with my slime mold collection because nobody else has one.

[laughs] So I have two drawers of this size, and I had to get another cabinet in my closet and start new drawers.

I've probably got about this many, four times over.

I would guess my collection is roughly in the 200, 500 range, thereabouts, maybe [laughs], for now, and counting.

But there's not a lot of people collecting slime molds in the whole world, actually.

NARRATOR: One of Kelly's inspirations and role models was a British naturalist in the 1800s.

Gulielma Lister and her father published the first definitive book on slime molds, which she illustrated herself.

KELLY: The description of hundreds of species, and then just the amount of art, all of these species that she illustrated.

[pages rustling] And there's so many.

Miss Lister was an amateur and not a professional scientist.

NARRATOR: From Lister's time to today, it has been passionate amateur naturalists, often working in isolation- Oh my goodness.

Who've taken it upon themselves to champion the little-known and under-appreciated slime molds.

I am not a slime mold expert.

I'm a slime mold hobbyist.

I don't have any credentials.

The only college I have was audited courses because I grew up in poverty.

I have found in the park that people appreciate the knowledge that I have gleaned on my own.

I have found people that appreciate me, so I think slime molds need to be appreciated, you know?

They're under-appreciated.

[birds singing] So I am definitely like reclusive and I love to hide in the forest and I love to be unobserved.

And maybe I haven't interviewed yet, I don't know, but I love just the weird quirkiness of slime molds.

That's also why I love things like lichens or nudibranchs because they're just kind of weird and quirky and overlooked, vastly overlooked.

I can relate to that.

I can relate to the organisms that people don't care about.

[laughs] It's like a personal thing, like bringing awareness to something that's been overlooked that is deserving of attention is just something that I feel strongly about.

I mean, slime molds, yeah, they deserve attention.

[laughs] Look at these guys, they're cool!

How cool can you get?

You're orange, you live in the woods, you're structurally absolutely beautiful.

What's not to like about a slime mold?

[warm music]