Submitted by Carolyn Bobo on Wed, 2012/05/02 - 12:25pm
Its face had an expression like a giant bulldog, with fang-like teeth and an upturned jaw that could open wide to consume large prey. Its flippers had the appearance of wings. With more than 100 vertebrae along the backbone, it resembled a 15-foot Atlantic tarpon.
This 250-pound fossil is of the head and flipper of the prehistoric Xiphactinus (pronounced Zie-fak-tin-nuz) Audex fish, a menacing predator that lived between 100 and 65 million years ago. The fossil is displayed in the Environmental Education, Science and Technology Building, first floor.
This fossil was discovered in late 2010 by Denton County resident Paul Jones and his daughter Maggie, and identified as Xiphactinus by George Maxey, lecturer in geography and director of the Meteorite, Rock, Mineral and Fossil Identification Lab. Above and right, Maxey and Xiphactinus.
He described the Xiphactinus Audex as a "fast-swimming, aggressive predator" that lived in coastal waters that once covered parts of what is today Denton County.
Maxey dates the specimens as being 90 to 100 million years old, from the Late Cretaceous period, and says they're among the most exceptional finds that have been brought to the lab since it opened in 2010.
How often do people bring fossils to identify?
We receive calls every day, and several times a week specimen are brought into the lab. Last year we had calls and performed identification on over 200 meteorites, or as it turned out, meteorwrongs. Last year we had 80 or so calls or actual fossil brought in. I don’t keep count of every rock that is brought to me for identification, but I would say we get thousands. Last year a fossil collection containing several thousand pieces was donated to the university. Occasionally, I will go to someone’s property if the objects are too large to transport. One lady had five gallon buckets full of rocks for me to identify. Another had a barn full of rocks. One gentleman had his entire house full of samples, rocks on shelves, on the floor, everywhere. There must have been tons of rocks in the house. We only keep records on specimen that take a few tests to identify. If I can just tell a person what their rock or fossil is just by looking, I will do that.
How many of these are of scientific or professional interest?
That is a tough question. Every rock, fossil and meteorite is a part of the history of the earth, our solar system or universe. A specimen of scientific interest should contribute new information to the body of knowledge of that academic discipline. Fossils may be interesting, but may be very common, like the gryphaea. Gryphaea, right, is a fossil that is quite often brought in for identification. People often mistake it for the claw of a dinosaur. As a geologist I find just about every rock, fossil and meteorite interesting, but that does not mean the specimen will contribute to scientific knowledge.
Why are people, especially children, so fascinated by fossils (and dinosaurs)?
These fossil creatures inspire the imagination. All we have to study are the bones, therefore assigning the fleshly appearance to these creatures is left to the imagination. Bones, while scary, cannot harm, and this allows the child to interact with confidence, explore ideas and be the master of these once scary, powerful creatures.
Are students aware of the geology and pre-history of North Texas?
No. I have read books that refer to the geology of the North Texas area as boring. Nothing could be further from the truth. This area has many different lithologies (types of rocks), and an incredible variety of marine invertebrates. The coastal environment of what is today North Texas has also yielded up quite a few vertebrates. There has been finds of marine fish, shark, mosasaur, pliosaur and a variety of terrestrial quadrupeds and biped dinosaur. In the Pleistocene, sediments - fossils of mammoth, mastodon, camel, bison and many other species.
What topics are most popular?
Dinosaurs are always popular for kids of all sizes. Probably the most asked question is, “what did this thing look like when it was alive?” and the second most asked question is, “was it a meat eater?”
Meteorites are really capturing the imagination of the public in part due to a show called the Meteorite Men on the Science Channel. Unfortunately, less than one percent of the objects brought for identification are actually meteorites. We respectfully refer to the objects as “meteorwrongs.” That also means we have to educate people on the properties of a space rock. Meteorites are pieces of material from outside our planet that survived the passage through our atmosphere without burning up.
How did your UNT students become interested in geology?
Some rare students do come into class with a love of geology. Most students take physical geology as a science requirement and that course is their introduction to our earth, its composition and history. I hope that they find the course interesting. It is really wonderful when I hear that a student wants to major in geology, even though we do not have a geology degree, so we lose those students.
- Nancy Kolsti, News Promotions, and Carolyn Bobo, InHouse content editor
(Photo by Jonathan Reynolds; Gryphaea arcuata courtesy of Tyne & Wear Museums, UK.)