Breaking new dino ground
An Augustana College researcher's team unearths paleontological gems in Antarctica: fossils of newly discovered dinosaur species that will eventually find their way to Chicago
Breaking new dino ground (Photo by William Hammer)
January 25, 2004
By William Mullen
Tribune staff reporter
Published January 25, 2004
Returning to a windy, rugged, almost impossibly cold mountainside where 13 years ago he excavated the first dinosaur fossils ever found in Antarctica, a paleontologist from little Augustana College struck new pay dirt, remains of a 200-million-year-old, 30-foot-long creature--fossils that will eventually make their way to Chicago.
Recovering the animal's pelvis and various leg bones, William Hammer, a geology professor at the Rock Island school, said he thinks the newly discovered fossil is an extremely early species of sauropod, plant-eating animals that 150 million years later evolved into 100-foot giants, Earth's biggest terrestrial animals.
The fossil was discovered by the six-man expedition's only non-scientist, a mountaineer who went along simply to watch over the safety of the dinosaur prospectors.
Bad weather in December hounded Hammer's team as it worked at 12,500 feet on the side of Mt. Kirkpatrick, 400 miles from the South Pole.
The expedition marked the return to the site where, in January 1991, a Hammer-led expedition found mainland Antarctica's first dinosaur, a 25-foot-long meat-eating theropod, Cryolophosaurus.
The 1991 team also recovered fragments of a still-to-be-named plant-eating prosauropod, a forerunner of sauropods, one that Cryolophosaurus may have been feeding on when the carnivore died.
Cryolophosaurus (cry-o-lo-fo-SOR-us) caused a sensation, important evidence that through much of Earth's history the global climate was much warmer than today.
It also helped verify the theory of Pangea, the super-continent that contained all of the world's landmasses until it began to break apart roughly 200 million years ago, first into two super-continents, Laurasia and Gondwanaland, then, tens of millions of years later, into today's continental landmasses.
Scientists know Africa, South America, Australia and Antarctica once formed one landmass--Gondwanaland--because they have found fossils of the same ancient plants and animals spread across them.
The rock formations on Mt. Kirkpatrick where Hammer has been working are some of the few to be found in the world surviving from the early Jurassic period. As such, the fossils he recovers give scientists an extremely rare look at the flora and fauna at the time early dinosaurs were still vying to dominate Earth.
"There aren't many sites in the world where you can go to get good early Jurassic specimens," said Philip Currie, one of the world's preeminent experts on theropods, the two-legged meat-eaters that include Tyrannosaurus rex.
"I was thrilled to get the chance to be a part of this expedition," said Currie, curator at Canada's Royal Tyrell dinosaur museum in Alberta. Normally he specializes in excavating theropod fossils in North and South America from the late Cretaceous period, the last living dinosaurs before the great extinction 65 million years ago.
"It is much easier to understand the late Cretaceous specimens and where they came from biogeographically if you can look at something far more primitive," said Currie.
Hammer wasn't able to remove all of Cryolophosaurus' bones from the site in 1991. He prospected in two other sites hundreds of miles from the Transantarctic Mountains in two subsequent Antarctic expeditions, in 1995 and 1999, so the December expedition was the first to return to Mt. Kirkpatrick.
"We had marked the Cryolophosaurus site with a big stone cairn of piled-up loose rock," said Hammer, "topped with a signal flag.
"When we found it in December, the flag had been long-since shredded by the strong winds that whip across the mountain, but everything else looked exactly as we had left it.
"We even found a roll of toilet paper in a burlap bag that somebody had left behind."
December's expedition had been funded by the National Science Foundation for three weeks of fieldwork. The scientists slept in tents at a lower elevation about 40 miles from the site. Two helicopters assigned to their camp flew them to the site each day.
"Instead of three weeks," said Hammer, "we only got to work for a few days, first because of severe weather, then because of mechanical trouble with one of the helicopters."
Once back at the site, Hammer, Currie and three other trained excavators, including 2002 Augustana graduate Nathan Smith from suburban Crystal Lake, toiled in high winds and temperatures as low as -40 to pull more of Cryolophosaurus from the rock.
The team also found rock with what they believe may be fossilized impressions of the skin of a theropod at the site.
The sixth member of the team, Peter Braddock, 57, a New Zealand mountaineer and veteran of 22 years of Antarctic work, was assigned to the group to guide them safely across mountain terrain.
"Peter told me he didn't want to stand around while we worked, so he was going to wander to some other parts of the mountain," Hammer said.
"I asked him to keep his head down and look at the rock for fossils as he walked and showed him what to look for. If he found anything he was supposed to mark it and bring me back later."
A couple of hours later, Braddock returned and took Hammer to look at a half a dozen interesting rocks he found about a quarter mile from the Cryolophosaurus site. Most indeed were fossils, but of ancient tree limbs rather than bone.
"The one thing he was least sure of turned out to be bone," said Hammer, "so the whole team went up to excavate it."
That turned out to be what may be one of the earliest sauropod fossils ever discovered.
"If it is what it seems to be," said Judd Case, a sauropod authority who teaches at St. Mary's College of California, "it will be a very important transitional specimen, a very early sauropod showing us how they evolved from primitive prosauropods.
"The prosauropods had the familiarly shaped skulls and longer necks that we see on the later, giant sauropods, but had rather spindly legs and bodies. What Bill found on this trip has the thicker, more elephantine legs of the later sauropods."
The team left most of the bone it found encased in the surrounding rock in which it became fossilized, flown to the main U.S. Antarctic base at McMurdo Sound. It will be sent to the U.S. by ship before spring.
"We won't really know what we have until we can remove the rock from the bones and get a better look at it," said Hammer, a process that might take the rest of this year.
Hammer's dinosaurs are approximately two times more removed in time than humans are from the last dinosaurs that roamed the world, living about 130 million years before the great dinosaur extinction 65 million years ago.
Hammer has been to Antarctica seven times in the last four decades, beginning as a graduate student in 1977 as a protege of the pioneering Antarctic paleontologist, John Cosgriff of Ohio State University. After Cosgriff died in 1985, Hammer, by then teaching at Augustana, took the mantle as the leading Antarctic dinosaur expert.
Eventually his dinosaurs will find a home in Chicago. Also a research associate at the Field Museum, he has promised to send the Antarctic fossils to the Field's permanent collection once he has finished studying them.
With the additional bone collected in December, Hammer said he believes he has more than half of the complete skeleton of Cryolophosaurus but still had to leave more fossils in the rock at the site.
"We'd like to go back," he said. "We saw some other very promising sites in the mountains from the air. I suppose I am getting to be at an age where I will have to start looking for somebody else to do this, but I'd like to get back there again."
