Nature & Environment

The Trinity Project: More About Bones

Essay 2 of 10

Dr. Ellis W. Shuler excavating a mammoth skull in Dallas, ca. 1934.
Dr. Ellis W. Shuler excavating a mammoth skull in Dallas, ca. 1934.

In addition to Pioneer Cemetery, there’s another quiet space in Dallas that holds the bones of ancestors: the Shuler Museum of Paleontology, located on the SMU campus. The Shuler Museum has no fully assembled skeletons of prehistoric carnivores on premises or other dazzling displays (though the day I visited, there was a stack of giant turtle shells in plaster jackets in the hallway, outside the entrance). For one, the museum is a shoebox of a space located on the basement floor of the Earth Sciences building. There isn’t the room for that sort of thing. Second, the fossils here function as teaching and research collections. A casual visit from a non-expert like me requires an appointment and a great amount of patience from the host, which I received in abundance from vertebrate paleontologist and museum director Dale A. Winkler.

The museum is arranged library-style with mastodon tusks and similar large bones laid out neatly on gray industrial shelving, while smaller specimens — teeth, small bone, shell, scute, and more — are held in cabinets with pullout trays lined in soft material and organized by collection. The occasion for my visit was to view those specimens described by Bob H. Slaughter and others in the 1962 report “The Hill-Shuler Local Faunas of the Upper Trinity River, Dallas and Denton Counties, Texas.”

My questions, then as now, are basic: what kinds of animal roamed the area now known as the Great Trinity Forest? What kinds of plants and trees were present? What was the climate like? How was the Trinity River floodplain formed?

Answers to these questions can be supplied in part because there’s a fossil record, thanks to the efforts of Winkler, Slaughter, and Ellis W. Shuler, the person for whom the museum is named. Shuler was hired by SMU in 1915, the year it opened, to teach geology and related courses. He served as head of the Geology Department and Dean of Graduate Studies until his retirement, in 1953.

As a researcher, Shuler often wrote about subjects close at hand: dinosaur tracks at Glen Rose, geology of Dallas County, terraces of the Trinity, and vertebrate fossils in river deposits. In a 1934 report, he posited, “The industrial use of sand and gravel in the City of Dallas has uncovered almost daily over a period of 50 years bones of fossil elephants.” That’s because, according to Shuler, “the best preserved fossils are found in the sand terraces along the Trinity river about 50 feet above the present floodplain.”

He did more than observe Dallas’ “fossil elephants” (or more precisely, mammoths); he convinced the operators of local quarries, who routinely tossed fossil remains “aside on the dump heap,” to allow him to excavate. That’s no small task, getting a business to stop the wheels of progress to dig for fossil elephants. This is especially true for sand and gravel operations, which have been a lucrative enterprise in the Dallas area since at the early 1840s. Sand and gravel, then as now, provide the essential ingredients for building a modern city — roads, runways, structures, pipelines, culverts. A Dallas Morning News headline from 1946 says it all: “No Oil on Your Land? Then Try for Gravel.”

In the late 1950s, Slaughter continued the tradition Shuler had begun. He was given permission from Dallas quarry owners to excavate fossil-rich zones. Two of those quarries — called the Moore pit and the Wood pit — were located 700 yards apart in an area off South Loop 12 (now called South Great Trinity Forest Way). A third site, called Pemberton Hill, was situated 400 yards to the northwest of the Moore pit.

Labor at these three locations unearthed evidence of: ancient camel, bison, armadillo, sloth, saber-tooth cat, mastodon, mammoth, wolf, tapir, turtle, crocodile, eagle, a variety of horses, vole, mink, hare, and more.

During excavation at the Moore pit, one of the numerous clay balls regularly encountered in the sand was inadvertently sliced open. Inside was a coprolite (fossilized dung) that contained the hard parts of insects, later identified as: beetle, ant, bee, wasp, stink bug, leaf bug, cockroach, cricket, millipede, and centipede.

Slaughter and colleagues dated the alluvial deposits where specimens were found in excess of 37,000 years, or late Pleistocene. For an age comparison, the city of Dallas received its town charter a mere 160 years ago.

Once the Moore and Wood pits had been depleted of sand and gravel, and excavation stopped, another enterprise emerged in the early 1980s for which the citizens of Dallas continue to pay. The giant holes from mining were filled with trash — illegal, hazardous trash over a long period of time.

What Slaughter called the Wood pit, a mining operation located at the south end of Deepwood Street, was at the heart of Herman Nethery’s notorious Deepwood landfill. In 1997, the massive landfill caught fire and burned for 52 days. After an extensive environmental cleanup on the city’s dime, the site became the Trinity River Audubon Center in 2008.

Not all municipalities treat their mammoth sites the same way, and at least one North Texas gravel pit owner has reached out to paleontologists with an invitation to dig, rather than the other way around. The “fossil-rich alluvial terrace deposits” of Shuler’s and Slaughter’s time are of our time, too. What will we choose to do with the resources under our stewardship in the name of progress?

[Editor’s note: an explanation of the Trinity Project can be found here.]