Scientists solve mystery of prehistoric "monster"

[jpak]

http://www.cbsnews.com/news/tully-monster-mystery-scientists-identify-strange-prehistoric-creature/

A prehistoric creature known as the Tully Monster (official name: Tullimonstrum gregarium) has puzzled scientists since it was first discovered by an amateur fossil collector in Illinois in 1958. The bizarre aquatic creature, which lived more than 300 million years ago, possessed a tube-shaped body and a long proboscis, or snout, tipped with a tiny jaw with teeth. Its eyes dangled at the end of short stalks. Paleontologists, who characterized the creature as a soft-bodied invertebrate, didn't know if it was a worm, a mollusk or a shell-less snail.

But now, after an analysis of over 2,000 specimens from the Field Museum in Chicago, this monster has its place on the tree of life.

Yale graduate student Victoria McCoy and colleagues from the Field Museum of Chicago, Argonne National Laboratory, and the American Museum of Natural History say their research shows that the animal was a vertebrate similar to today's lamprey.

"This is important because it confirms our general view that by 300 million years ago, most animals fell within the major groups we know today," McCoy told CBS News via email. "Also, the group of modern lampreys today is just a remnant of a much larger, more diverse group that existed in the past. By identifying the Tully Monster as a stem lamprey, we are beginning to see the range of diversity that existed in that group."

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a lamprey with jaws - WTF?

[petronius]

1. That reconstruction is creepy/awesome! I'm morbidly curious about its eating

habits: was that proboscis used to snare prey, or did it root around inside the carcass of larger carrion?

[jpak]

2. modern lampreys are jawless - they have a nasty oral disk with lots of denticles

and a nasty rasping tongue.

This monster had "jaws" that may or may not be homologous with true jaws.

Reminds me of Anomalocaris



Very strange...

[Retrograde]

3. They've let all sorts of weird critters into our phylum

Lampreys - well, they're kinda fishlike. Hagfish - that's pushing it: they're not the sort of relative I'd invite to Thanksgiving dinner. Sea squirts - they consume their own brains on reaching adulthood, so I suppose they're sorta like neo-cons. And now this - a poster critter against Intelligent Design!

It's a fascinating creature. What was it after with that long snout with the jaw on the end? Are those teeth out there at the end? Why did our ancestors get rid of eyes on stalks?

[muriel_volestrangler]

4. It's not really ancestral to us - it seems to have developed the eyes on stalks

and I can see the similarity to a lamprey, just with a narrow section between the eyes and jawless mouth (the Tully monster didn't have a true 'jaw' with bone):



The eyes weren't on very flexible stalks, but a rigid bar.

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature16992.html

This guy lived just over 300 million years ago, but jawed fish developed over 400 million years ago: http://www.earthlife.net/fish/evolution.html
http://www.reuters.com/article/us-science-fish-idUSBREA1B22Q20140213

[Orrex]

5. I really thought we were talking about this guy: