WoRMS

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Emily: This episode is made possible through a partnership

with the Smithsonian’s National Museum of Natural History in Washington DC

and the Field Museum in Chicago, Illinois.

Emily: What comes to mind when I mention worm?

My initial thought is of these creatures, earthworms.

The species most individuals recognize is a "Lumbricus terrestris,"

often called night crawlers.

However, I recently discovered that there are about six thousand identified and classified species of earthworm alone.

This merely scratches the surface of the worm topic.

There's so much more to learn about them,

primarily because the term worm is a deceptively ambiguous notion with no straightforward definition or description.

In reality,

there may be as many as a few

hundred thousand species of worms, with some being as distinct from one another as you or I are from a

starfish. To assist me in addressing the question What constitutes a worm?

I visited the Smithsonian’s National Museum of Natural History to speak

with Dr. Anna Phillips, one of the three curators of worms.

Emily: We are here; in which collection are we located?

Anna: We are in the invertebrate zoology collections at the

National Museum of Natural History, the Smithsonian; this room contains everything from mollusks to

arthropods and crustaceans to worms.

Emily: How many worms are there in the collection here?

I mean the Smithsonian Museum possesses some of the largest collections

in the world, if not the largest worm collection.

Anna: We have at least four hundred and twenty-seven thousand specimens of worms;

we likely have more.

Emily: So, can you clarify what constitutes a worm?

Anna: There are organisms that tend to be long and thin and

lack backbones.

There are many entities that can fit that description that may not actually be classified as worms,

so it’s somewhat of a complex question. It’s a broad term that refers to a kind of body structure.

It might be surprising to some, but there are numerous types of worms

present. It turns out there are about 12 phyla of worms globally.

Emily: So if you visualize the taxonomic tree of life, what does it signify to belong to a

distinct phylum?

Anna: It goes from kingdom, phylum, class, order,

family, genus, species. The phylum indicates that they’re all within the animal kingdom

and they all have significant differences from one another.

Emily: So which phylum do humans belong to?

Anna: We belong to Chordata, yes.

Emily: Thus, we are more closely related to

squirrels, lizards, and snakes.

Anna: And fish.

Emily: And fish,

than any of these worms are connected to each other.

Anna: Correct.

Emily: Can we now discuss some of these various worms since we understand

that the term worm serves as a broad

label?

Anna: Here we have a selection of some worms; some of these are the larger specimens.

We possess a variety that includes some Polychaetas; these are aquatic worms, and we also have worms that inhabit vertebrates such as

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Autoscroll

Emily: This episode is made possible through a partnership with the Smithsonian's National Museum of Natural History in Washington DC and the Field Museum in Chicago, Illinois.

Emily: What comes to your mind when I mention worm?

My initial thought is of these creatures, earthworms.

The species that most people recognize is the "Lumbricus terrestris," often called night crawlers.

However, I recently discovered that there are approximately six thousand identified and described species of earthworm alone.

This only scratches the surface of the worm iceberg.

There is a vast amount more to learn about them.

Primarily because the term worm is a surprisingly ambiguous concept with no straightforward definition or description.

In reality,

there might be as many as a few

hundred thousand species of worms, and some can vary as much from each other as you or I do from a

starfish. To assist me in answering the question, What is a worm?

I visited the Smithsonian's National Museum of Natural History to speak

with Dr. Anna Phillips, who is one of three curators specializing in worms.

Emily: We are here, which collection are we in?

Anna: We are in the invertebrate zoology collections at the

National Museum of Natural History, the Smithsonian. This room contains everything from mollusks to

arthropods and crustaceans to worms.

Emily: How many worms are in the collection here?

I mean, the Smithsonian Museum has some of the largest collections

in the world, if not the most extensive worm collection.

Anna: We have at least four hundred and twenty-seven thousand specimens of worms;

we likely have more.

Emily: Can you explain what a worm is?

Anna: There are organisms that tend to be long and thin,

and they lack backbones.

There are many things that might resemble that but may not be true worms,

so it's a somewhat challenging question. It's a broad term that refers to a specific body plan.

It might surprise some, but there are numerous kinds of worms

in existence. It appears there are about 12 phyla of worms around the world.

Emily: And if you picture the taxonomic tree of life, I guess what does it signify to belong to a

distinct phylum?

Anna: The hierarchy goes from kingdom, phylum, class, order,

family, genus, species. A phylum indicates that they’re all part of the animal kingdom,

and they are all quite distinct from each other.

Emily: So which phylum do humans belong to?

Anna: We are in Chordata, yes.

Emily: Therefore, we are more closely related to

squirrels, lizards, and snakes.

Anna: And fish.

Emily: And fish,

than any of these worms are related to each other.

Anna: Correct.

Emily: Can we discuss some of these various worms now that we understand

that the term worm is essentially a broad

description?

Anna: Here we have a collection of various worms. Some of these are the larger examples.

We have everything from some Polychaetas.

These are marine worms and then we also have worms that live inside vertebrates like

Nematodes,

Tapeworms, and several larval stages of parasitic worms.

Emily: Like this one, these strange balloon-shaped things.

Anna: So these are larvae of tapeworms.

Emily: Those are young tapeworms.

Anna: Yeah.

Emily: Really adorable.

Anna: It’s a bit different because they have intricate life cycles so they will go through this larval stage

On their path to becoming an adult in a different host.

You wouldn’t easily recognize that this worm closely resembles this.

Emily: Yeah, like I mean this resembles some spaghetti.

Anna: Yeah, many people liken it to pasta.

Emily: We probably shouldn’t say that; it could ruin pasta for some people.

Anna: Don’t eat tapeworms.

Emily: Yeah, no, no, that’s a bad idea.

Do not, not a good, not a good

Anna: Not an endorsed weight loss strategy.

Emily: What other worms are we discussing today?

Well, check out this guy!

Anna: Yeah, this is one of my favorite specimens.

Emily: Who is this?

Anna: This is a giant leech.So this is the giant Amazonian leech, so you can guess where they are found. Generally in the wild,they’re a bit smaller, so this one lived in a lab and had an abundance of food.

Emily: And when you say food, i mean, are you placing kibble in its tank?

Anna: No, this one feeds on blood. We fondly refer to this leech as Grandma Moses because she is quite large.

Emily: How long did she reside in the lab?

Anna: I’m not sure, but there’s a very famous photograph of a well-known leech biologist with Grandma Moses resting on his arm.

Emily: I, you know,I really feel as if I’ve encountered acelebrity leech today,and they’re part what type of worm are they?

Anna: They belong to the phylum annelida. So,leeches, they are our closest relatives to earthworms. They appear a bit different to a scientist because we know to look for certain characteristics, namely because they have that blood-sucking trait, whereas earthworms do not, but one thing that connects earthworms and leeches is that they are hermaphrodites, so they possess both sexes at once. Oh, while the next closest relatives are the polychaetes.So like your marine worms, the bristle worms, many of those have separate sexes.

Emily: How does one gather leeches?

Anna: It depends on which type of leech you are trying to collect. So my research focused on medicinal leeches that prefer to feed on humans. That involves venturing into locations where you anticipate finding leeches,such as lakes, ponds, and streams,rolling up your pant legs and wading in. You create some movement,you perform the leech dance, as I like to call it.