Danielle de Carle

So the fossil that we found, it wasn't found alongside any real large vertebrates.

So we think that instead of parasitizing vertebrates, which is sort of the prevailing hypothesis for what the oldest leeches did, we think that our fossil instead would have either preyed on other animals by kind of swallowing them whole, or it might have been a parasite of invertebrates, of larger animals like trilobites.

They also included photos of some fossils that were beautifully preserved, but they weren't entirely sure yet exactly what they might be.

OK.

Another mystery.

Karma saw one of them.

Yes.

Another mystery.

So Karma saw one and he thought it might be a leech.

So he brought it to myself and our other co-author, Rafael Luama, who's also a leech scientist.

And he was very excited about how this might be a leech.

And instantly, Rafa and I both were like, no, I don't think so.

After we rejected Karma and we threw his first hunch out the window, we decided to get in touch with Andrew and Lauren.

And they were kind enough to share some photos of a lot of animals that they, or a lot of fossils from the Waukesha site that they hadn't yet identified, which included some other segmented worms.

And one that immediately leapt out at us was this one that we ended up describing as Macromizon, as the first fossil leech.

And this one did, in karma's defense, have lots of similarities to that first fossil.

But it wasn't the one he showed you, is what you're telling me.

Yeah, it had a little bit of extra detail in there that sort of made us feel really confident.

And the first thing in particular that we noticed was that big sucker that it has at the posterior end, which is something that's a huge hallmark of leeches today as well.

But you know, it's courage, right?