Hurricane Ike yields mammoth ice-age discovery
When Lamar University professor Dorothy Sisk returned to her beachfront home in Caplen, she knew there would be little left.
Instead, she was part of a discovery of something that tells a different story of Texas’ continually changing coastline.
Taking little with her when she evacuated before Hurricane Ike, she searched through what few belongings were strewn about —a bowl, a broken vase, a scrap of fabric.
“She picked up a couple things,” said LU colleague Jim Westgate, who had volunteered to drive her to the site in his pickup. “We searched through a little scrub forest across the highway and she recognized a few things.”
All that remained of the home west of Rollover Pass were scraps of concrete and splintered pilings.
“It was while we were looking at the house, or at least what was left of the foundation, that I saw it lying there with lots of shell debris in what had been the front yard,” Westgate said.
What Westgate, a trained paleontologist and a research associate with the Vertebrate Paleontology Laboratory at the University of Texas Memorial Museum, recognized was the fossil tooth of a mammoth.
“This is the first one I’ve found in 19 years,” Westgate said.
“People bring in pieces and parts from the beach for me to identify, and I haven’t seen one in this good a condition.”
The 6-pound tooth, which resembles a series of boot soles or slices of bread wedged together, is most probably that of the Columbian Mammoth (Mammuthus columbi), a species common to North America until around 10,000 years ago, Westgate said. Ancestors of the modern elephant, mammoths and mastodons roamed the continent in large numbers.
Their fossil teeth are easily distinguished from one another by the grinding surface, Westgate said. Mastodon teeth are bumpy, and resemble a series of steep mountains and deep valleys, whereas mammoth teeth are flatter and well-suited to grinding. The diet of the mastodon is believed to have comprised leaves, bark and fruits, whereas mammoths were predominately grazers.
Like modern elephants, mammoths grew a total of six sets of teeth during their lifetime, ejecting worn teeth “like a shotgun, loading a newly formed tooth in its place,” Westgate said. The discovered tooth is unworn, so it was either newly erupted or a “tooth in waiting” when the animal died, Westgate said.
How likely is it to find fossils in the area? “It is pretty common after we’ve had storms,” Westgate said. “McFaddin beach is a hot spot with local collectors. After a storm, or when a blue northern has blown in and the water is pushed way off shore, they will go down the beach looking for fossils.”
What they’re likely to find are examples from the fossil record of a world much different than the seascape of today, Westgate said.
The area is well known for fossil mastodon, mammoth, ground sloth, tapir, camels and other late Pleistocene (Ice Age) mammals.
Russell Long, professor emeritus of biology at Lamar from 1951 to 1979, had an extensive collection of fossils from the area and
supervised a master’s thesis by Jeffrey Russell in 1975 that detailed the megafauna of the region documenting a wide array of extinct animals including the above, as well as saber-toothed cats, early horses and more.
Westgate said the fossils likely come from ancient stream channels where the bones collected when the land that is now beachfront was 100 or more miles inland.
But don’t expect every bone you find to be a genuine fossil. “A lot of time you can’t tell if it’s a fossil or not,” Westgate said. “Bison bones look just like cow bones. If you bury a cow bone in that dark mud it stains pretty quickly. So, the ones we know for sure are at least 10,000 years old are the ones that are extinct locally, like mastodon, mammoth, ground sloth, tapir and camels.”
Also, don’t expect to find complete skeletons or easily recognizable skulls. Mammoth skulls, while massive, are fairly fragile. It is
unlikely, Westgate said, that such structures would have survived intact. “Skulls look pretty solid on the outside, but really they are thin bone,” he said. “Teeth tend to survive the process.”
The fossil will join the collection of the Texas Memorial Museum in Austin and “Dorothy’s address will actually be the site locality for this specimen. Normally we don’t have house addresses for our fossil localities,” he said.
“There are stream channels sitting off shore waiting to be excavated by storm waves,” Westgate said.
While those future storms will bring their share of loss, they may also bring discovery.