The Mysterious ‘Tully Monster’ Fossil Just Got More Mysterious

Posted by on November 12, 2019 in Sci-Tech, Science with 0 Comments
image_pdfimage_print

Artist’s impression of Tullimonstrum. Credit: PaleoEquii/Wikipedia, CC BY-SA

By Chris Rogers | Phys.org

Every now and again, scientists discover fossils that are so bizarre they defy classification, their body plans, unlike any other living animals or plants. Tullimonstrum (also known as the Tully Monster), a 300m-year-old fossil discovered in the Mazon Creek fossil beds in Illinois, US, is one such creature.

At first glance, Tully looks superficially slug-like. But where you would expect its mouth to be, the creature has a long thin appendage ending in what looks like a pair of grasping claws. Then there are its eyes, which protrude outward from its body on stalks.

Tully is so strange that scientists have even been unable to agree on whether it is a vertebrate (with a backbone, like mammals, birds, reptiles, and fish) or an invertebrate (without a backbone, like insects, crustaceans, octopuses and all other ). In 2016, a group of scientists claimed to have solved the mystery of Tully, providing the strongest evidence yet that it was a vertebrate. But my colleagues and I have conducted a new study that calls this conclusion into question, meaning this monster is as mysterious as ever.

The Tully Monster was originally discovered in the 1950s by a fossil collector named Francis Tully. Ever since its discovery scientists have puzzled over which group of modern animals Tully belongs to. The enigma of Tully's true evolutionary relationships has added to its popularity, ultimately leading it to become the state fossil of Illinois.

The mysterious 'Tully Monster' fossil just got more mysterious

The Tullimonstrum fossil. Credit: Ghedoghedo/Wikimedia, CC BY-SA

There have been many attempts to classify the Tully Monster. The majority of these studies have focused on the appearance of some of its more prominent features. These include a linear feature in the fossil interpreted as evidence of a gut, the light and dark banding of the fossil and the peculiar grasping claws of its mouth. The body plan of the Tully Monster is so unusual in its entirety that it will greatly expand the diversity of whatever group it ultimately belongs to, changing the way we think about that group of animals.

The 2016 research argued the animal should be grouped with vertebrates because its eyes contain  called melanosomes, which are arranged by shape and size in the same way as those in vertebrate eyes. But our research shows that the eyes of some invertebrates such as octopus and squid also contain melanosomes partitioned by shape and size in a similar way to Tully's eyes and that these can also be preserved in fossils.

Particle accelerator research

To do this, we used a type of particle accelerator called a  light source located at Stanford University in California. This allowed us to explore the chemical makeup of samples from fossils and from animals living today. The synchrotron bombards specimens with intense bursts of radiation to “excite” the elements within them. When excited, each element releases X-rays with a specific signature. By detecting the emitted X-ray signatures, we can tell what elements were excited and ultimately what the specimen we're interested in is made of.

The mysterious 'Tully Monster' fossil just got more mysterious

Another possible look for the Tully Monster. Credit: Nobu Tamura/Wikimedia, CC BY-SA

First, we found that melanosomes from the eyes of modern vertebrates have a higher ratio of zinc to copper than the modern invertebrates we studied. To our surprise, we then found the same pattern could be seen in fossilized vertebrates and invertebrates found at Mazon Creek.


We then analyzed the chemistry of Tully's eyes and the ratio of zinc to copper was more similar to that of invertebrates than vertebrates. This suggests the animal may not have been a vertebrate, contradicting previous efforts to classify it.

We also found that Tully's eyes contain a different type of copper that found in vertebrate eyes. But the copper also wasn't identical to that in the invertebrates we studied. So while our work adds weight to the idea that Tully is not a vertebrate, it doesn't clearly identify it as an invertebrate either.

Where do we go from here? A broader analysis of the chemistry of melanosomes and other pigments in the eyes of a wider range of invertebrates would be a good next step. This may help to further narrow down the group of animals to which Tully belongs.

Ultimately the riddle of what kind of creature the Tully Monster continues. But our research demonstrates how studying fossils at the chemical and molecular levels can play an important part in figuring out the identity of this and other enigmatic creatures.

Read more great articles at Phys.org

Tags: , , , , , ,

Subscribe

If you enjoyed this article, subscribe now to receive more just like it.

Subscribe via RSS Feed Connect on YouTube

New Title

NOTE: Email is optional. Do NOT enter it if you do NOT want it displayed.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

FAIR USE NOTICE. Many of the articles on this site contain copyrighted material whose use has not been specifically authorized by the copyright owner. We are making this material available in an effort to advance the understanding of environmental issues, human rights, economic and political democracy, and issues of social justice. We believe this constitutes a 'fair use' of the copyrighted material as provided for in Section 107 of the US Copyright Law which contains a list of the various purposes for which the reproduction of a particular work may be considered fair, such as criticism, comment, news reporting, teaching, scholarship, and research. If you wish to use such copyrighted material for purposes of your own that go beyond 'fair use'...you must obtain permission from the copyright owner. And, if you are a copyright owner who wishes to have your content removed, let us know via the "Contact Us" link at the top of the site, and we will promptly remove it.

The information on this site is provided for educational and entertainment purposes only. It is not intended as a substitute for professional advice of any kind. Conscious Life News assumes no responsibility for the use or misuse of this material. Your use of this website indicates your agreement to these terms.

Paid advertising on Conscious Life News may not represent the views and opinions of this website and its contributors. No endorsement of products and services advertised is either expressed or implied.
Top
Send this to a friend