Celebrating its 4th National Fossil Day, the Texas Memorial Museum in Austin offers events for children, the general public and teachers.
This museum is the exhibit hall of the Texas Natural Science Center (TNSC) at the University of Texas at Austin. The museum and scientific collections that are part of TNSC work together to create awareness, understanding and appreciation of the past, present and future of biological diversity, especially that of the state of Texas.
Within TNSC are the Vertebrate Paleontology Laboratory, the Non-Vertebrate Paleontology Laboratory and the Texas Natural History Collections. TNSC’s website states, “All exhibits and education/outreach programs are based on the Center’s collection of 6 million specimens, most of which are from Texas…”
Although not all of the specimens are fossils or from Texas, that number speaks to a wealth of natural resources and research programs and opportunities.
“[W]e in the Austin area are fortunate to be surrounded by fossiliferous Cretaceous limestone, which is the source of many discoveries of fossils by the community,” explained Dr. Pamela R. Owen, Senior Biodiversity Educator at TNSC.
Two fossils on exhibit and found in Texas are the Texas Pterosaur, described by the TNSC website as “the largest flying creature ever found”, and the Mosasaur, a substantial sea creature. (A recent study of a Mosasaur fossil in Jordan found that they may have had shark tails. You can read about that here: http://phys.org/news/2013-09-mosasaur-fossil-early-lizards-tails.html)
When asked to name the oldest fossil in its collection, Dr. Owen said, “We have a sectioned stromatolite formed by Precambrian cyanobacteria from Minnesota on exhibit at Texas Memorial Museum.”
Stromatolites are layered structures, most of which were built by cyanobacteria (aquatic photosynthetic bacteria with a long evolutionary history). These fossils are, in a way, the footprints of the activity of cyanobacteria, although some have been found that do have the bacteria trapped within them. Stromatolites date as far back as 3.5 billion years.
Chris Sagebiel, Collections Manager of the Vertebrate Paleontology Laboratory (VPL), named two different fossils as the oldest in the VPL Collection.
“Geologically speaking,” he wrote, “our oldest specimens are from Ordovician age rocks in the Arbuckle Mountains in Oklahoma.”
The Ordovician age, as we understand it today, was largely populated with sea creatures. There is evidence of primitive plants and life on land toward the end of the Ordovician. Horseshoe crabs—creatures we can see now on East Coast shores—are thought to have begun during this period.
“Our collection is home to one of the oldest bony fossils: a fragmentary skull and some scales from Eriptychius, a jawless fish that lived about 450 million years ago.”
“Eriptychius,” he continued, “is not terribly well understood. What has been found are only bits of skull and scales. Our Eriptychius fossils are not fully prepped out of the rock, so unless you were looking for Eriptychius fossils, the specimens look like any other rock. Some of the isolated scales have been cut for thin sections. Typically, a 30 micron thick section is taken from the scale to look at the micro-structure of the bone and scales. We do know that they had external armor, at least forming a head shield. They may also have been one of the earliest animals with enamel.”
Below are two images of the Eriptychius fossil and the section he described:
“…[T]he fossil is just the dark gray bit in the very center of the photo directly across from my thumb and directly below my index fingertip.”
“In terms of human years,” he explained, “the oldest is the Cope-Cummins fossil collection, collected in the early 1890s. Cummins was an itinerant preacher and geologist who collected fossils as part of a larger state geological survey that was conducted under the supervision of Edwin T. Dumble. Most of the fossils were sent back east to noted paleontologist Edward Drinker Cope, who reported on these for the Dumble survey report and elsewhere.”
He sent the image of the lower molars of Equus conversidens below:
2012 National Fossil Day – Mammoths!
Last year, National Fossil Day events at the TX Memorial Museum centered around mammoths. The theme reflected the 2012 artwork forthat day by the National Park Service.
[image of 2012 National Fossil Day, courtesy of the National Fossil Day website]
“My gallery talk,” Dr. Owen wrote in an email, describing her ‘Meet the Mammoths’ presentation, “was next to our Ice Age exhibit in the Hall of Geology and Paleontology, and I set up my table adjacent to the skull and tusks of a Columbian mammoth. That afternoon I had several family groups in attendance at each of my two scheduled presentations, so the energy level was pretty high and the kids all wanted to share their knowledge about mammoths (and the fact that they have seen at least one of the Ice Age movies!)
“We talked about the differences between Columbian mammoths and woolly mammoths and everyone had a chance to gently feel a molar from each species. I also had some large tusk and bone fragments for the visitors to see and feel.”
2013 National Fossil Day – Fossil ID’s, Teacher Workshops, and Common Misconceptions
Teachers are able to participate in workshops hosted the TX Memorial Museum. One of the workshops notes that there will be a discussion about “common misconceptions about the fossil record.”
Dr. Owen explained, “First of all, fossils are relatively rare; most organisms are not preserved after death. The remains of organisms stand a better chance of fossilization if they are rapidly buried by sediment. And not all fossils are preserved or even discovered. But the fossil record is complete enough to document evolutionary events and changes in biodiversity over millions of years.”
“One misconception,” she continued, “is that all fossils are simply impressions or organisms ‘turned to stone.’ Fossilization processes vary, resulting in differences in preservation. For example, wood, bone and shell can be altered by mineralizing solutions. Minerals in the water moving through sediment can fill pore spaces or completely replace the original material. Fossils preserved in this manner include ‘petrified wood’, pyritized sea shells, and dinosaur bone. Sometimes organic remains are preserved by compression, compaction and/or carbonization. Coal is formed from ancient plants by these fossilization processes. On the other end of the spectrum, we have fossils that are essentially unaltered, such as the frozen mammoths discovered in Siberia.”
“In the workshop, we will also discuss misconceptions about purported ‘gaps’ in the fossil record, radiometric dating of fossils and the formation of fossil fuels.”
(For more information regarding Lyuba, the best preserved baby mammoth found in Siberia to-date, please see this post: https://mostlymammoths.wordpress.com/2013/09/10/mammoth-article-qa-dr-daniel-fisher-renowned-paleontologist/)
What prompted you into a career in paleontology?
Dr. Pamela Owen:
I have always been interested in natural history, and as a child, I did go through a “dinosaur phase” but mammals have always held my fascination. I did not take a paleontological path in my studies until I started work on my master’s degree in biology. My thesis research was on the neck morphology of saber-toothed cats, American “lions”, coyotes and dire wolves at the Page Museum of La Brea Discoveries (at the infamous La Brea Tar Pits) in Los Angeles, California. More recently I have been focusing on badgers. I described and named a new species of extinct American badger as part of my studies for the Ph.D. I remain very interested in the evolutionary history of mammalian predators and enjoy my career as a museum scientist and educator.
I really couldn’t say how I became a paleontologist. I just have always been one. We had a farm with fossil bivalves and such poking out of the rocks. Several family members have degrees in geology, though none of them are practicing geologists, we always talk about geology. However, I was in my senior year of college before it dawned on me that I could make a career in paleontology. I was lucky that a spot was open for me in the graduate program at UT, and just happened to have a museum job open up when I completed my graduate degree.
If you are in the Austin area, please do not miss out on these events or the chance to see the fossils at the TX Memorial Museum!
Fossil Identifications at the Paleo Lab: 9 a.m.–noon and 2-4 p.m. Fossil Dig Pit: Young paleontologists can make their own discoveries from 2-4 p.m. Teacher Workshop (pre-registration required): Deep Time Explorations, 6-9 p.m. For more information send an email to Pamela R. Owen or call her at 512-232-5511. http://www.utexas.edu/tmm/events/nfd/ http://www.utexas.edu/tmm/education/profdev/deep-time/index.html
Many, many thanks to Dr. Pamela Owen and Chris Sagebiel!