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  • You wanna know a word that bugs me? At least one that bugs me when people use it to talk about natural history.

  • Monster

  • You see it all the time, like in blog posts that describes some awesome mosasaur fossil as a sea monster

  • or articles that try to get more clicks by calling a pterosaur a flying monster. Now

  • don't get me wrong. In the right context, monsters are awesome. The Harry Potter books, Stranger Things, the collected works of JJ Abrams.

  • They'd all be basically meaningless

  • if they didn't have monsters. But the problem with referring to actual organisms that lived on this earth as monsters is that monsters are by definition

  • IMAGINARY. They're made-up creatures that are so terrifying and so threatening to our sanity that they can't possibly be real. And yet there are

  • animals in the fossil record that challenge some of the most basic ideas about what animals are supposed to look like.

  • If there ever was a monster on this planet that was ready of the name, it might have been this: the Tully Monster.

  • It lived in the Inland Seas of North America 300 million years ago at the very end of the carboniferous period. Back then

  • rainforest covered much of the land and the seas teemed with life ranging from sharks to tiny shell covered protozoans. The Tully Monster wasn't, like,

  • monstrously large for its time. It was maybe a foot long. What makes it strange to modern eyes is that it just looks imaginary.

  • It doesn't look remotely like anything that's alive today, or maybe it looks more like a bunch of other things put together.

  • Which is just as creepy. I mean things like Mosasaurs at least bear some resemblance to reptiles we know,

  • like crocodiles or snakes or Komodo dragons. But the Tully Monster?

  • I mean if George Lucas ate a pepperoni pizza, and then drank a whole thing of chocolate yoohoo before going to bed,

  • this is what he'd dream up. Its body was long and tapered, built for life in the water. Like a giant worm crossed with a

  • small squid. It also apparently had eyes that flopped around on the sides of its body attached to these fleshy stalks. And out of its head came

  • this long skinny appendage with a claw at the end, which may or may not have been a mouth.

  • But that's just one interpretation of it, because what exactly this thing looked like depends on what exactly it was, and

  • scientists have been fighting about that since Tullys were first discovered in Illinois in the

  • 1950s. To paleontologists, if anything is creepy about the Tully monster, is that it's missing the one thing that biologists value very highly.

  • Phylogeny. Phylogeny is evolutionary relationship that every organism has to its ancestors and its descendants.

  • But the Tully Monster doesn't have a permanent place in the evolutionary scheme of things that we call the Tree of Life.

  • Not yet anyway. In 2015 some paleontologists at Yale thought they had found a home for it. After analyzing more than 1,200 fossils of the Tully Monster

  • they determined that the creature was a vertebrate, probably an ancestor of Jawless fish like lampreys. They came to this conclusion in part because of

  • a telltale mark that they found in some of the fossils. A white line that ran down the middle much like a backbone.

  • But instead of being made out of bone that spine was probably made of something like cartilage.

  • Forming a notochord like those still found in some of today's jawless fish.

  • So, that was as close to an answer as paleontologists could get. The Tully Monster was a member of team vertebrate.

  • But then, in 2017, another team of researchers gave the fossils another pass and came to the exact opposite conclusion.

  • They determined that they actually don't know what it is... still.

  • But they said Tully definitely was not a vertebrate. For one thing, the white lines found on some of those fossils go past the eyestalks

  • where true notochord would end. And other fossils of vertebrates found from the same period, like fossils of lampreys,

  • didn't have those white lines at all. Even Tully's bizarre dangling eyes don't seem to have been true complex eyes like other vertebrates have.

  • Instead, they might have been so-called cup eyes, much more simple light-sensing organs that are found in things like worms and mollusks.

  • So we're left with a mystery. We don't know this thing was a worm or a fish or a mollusk.

  • And we don't know how it's related to us or to anything else. But guess what? In the fossil record,

  • there's a lot more where that came from. There are animals like Banffia,

  • a sea creature that look basically like a swimming hot water bottle; and Opabinia, a Cambrian animal with five eyes.

  • There are many organisms out there whose phylogeny is a total mystery to us.

  • So many, in fact, that scientists have a special category for fossils that defy classification.

  • They call them problematica. But if we can find a home for creatures like these in the Tree of Life,

  • we'll have a much better understanding of what the rules of life are on our planet.

  • So, animals like Tully Monster are weird, definitely. And for scientists, they're frustrating. Absolutely. But a monster?

  • I prefer to think of it as problematic.

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The Tully Monster & Other Problematic Creatures

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    joey joey posted on 2021/05/04
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