22 April 2005

The Bone Bed: Excavating Dinosaur Remains in Wyoming

Julie Roberts, Director of Development, Earth History Research Center, Southwestern Adventist University

Each year in June, a group of scientists, college students and teachers sets out from Texas and elsewhere for a remote locality in eastern Wyoming, where they continue excavation of one of the richest dinosaur bone beds in the world. The remains of the hadrosaur Edmontosaurus, Triceratops, Tyrannosaurus rex, Pachycephalosaurus and other dinosaurs of the uppermost Cretaceous are found here in a bone bed nearly a meter thick. The project director, geologist Art Chadwick, remarks, "The problem is not knowing where to find bones…we are dealing with a bone bed that covered nearly a million square meters…the problem is knowing where to dig to obtain the best view of the taphonomy of the site."

Taphonomy, the scientific study of what happens to organisms from the time they die until they are excavated, is a rigorous science, requiring the preservation of every conceivable piece of data. To accomplish this goal, the team from Southwestern Adventist University in Keene, Texas, has innovated new techniques using high-resolution, satellite-based GPS and special software so that images of the bones can be reconstructed in the computer just as they lay in the ground without the surrounding soil and rocks. As a result, the investigators are able to address significant questions on the taphonomy of the site from their home base in Texas. The team has established and maintained an on-line database of all the bones they have excavated, so that other scientists can have access to the data.

Larry Turner, an astrophysicist in charge of the major technological innovations says, "We are definitely a high-tech operation, with an on-site satellite uplink to the internet that allows our remote site to have contact with the outside world. We uplink photos and diary accounts daily during the season and stream video to our Internet site, so that those who can't join us in person can participate vicariously."

"Science teachers comprise the backbone of the research team," states Chadwick, who enumerates a long list of high school, middle school and elementary teachers associated with the project. "We teach a college science class, but also offer CEU credit to participants." The program includes evening lectures, and daily experience in the quarries. Kathleen Wilson, an elementary teacher from Oklahoma who has participated in the dig for four seasons, adds, "It is hard work, but all of us want to return next summer."

Information on the dig, and on the results of excavations so far, can be seen on the dig web site at http://dinodig.swau.edu. You can also visit the on-line fossil museum at http://geology.swau.edu/fossil. Chadwick concludes, "This site contains the remains of over 10,000 dinosaurs. What killed them, where they were killed and how their bones came to be buried here are all mysteries we are trying to solve. There are no suitable answers in conventional paleontology. We are looking for fresh ideas from any source. Nothing is off the table."

 
Figure 1. The Hanson Research Station viewed from above. The camp, dubbed "Camp Cretaceous," is located in an isolated valley on a large cattle ranch in eastern Wyoming. The facility is home base for the team during their month-long stay at the site. Photograph by Justin Woods, June 2003. Click image to enlarge.
 
Figure 2. A typical array of bones (these are from a duck-billed dinosaur), including two fibulae (smaller lower leg bones) lying parallel in the center of the photo, a humerus (upper arm bone) lying perpendicular to the fibulae on the left and a metacarpal (wrist bone) at right center. Just above the hat is a large tibia (larger lower leg bone) just beginning to emerge from the sediment. Photograph by Justin Woods, June 2003. Click image to enlarge.
 
Figure 3. Amy Teague, a high school teacher from Cleburne, Texas, who has directed excavation for three years in a quarry that bears her name, sits among a mass of disarticulated bones illustrating the density of bones (this is typical) in the lower portion of the bone bed. These are all bones from the hadrosaur Edmontosaurus. Photograph by Justin Woods, June 2004. Click image to enlarge.
 
Figure 4. Zury Franco, a senior medical student at Loma Linda University in California, holds a large humerus from Edmontosaurus she excavated from one of several active quarries in the bone bed. Zury has participated in the dig for five years, taking summer breaks from her studies. Photograph by Justin Woods, June 2004. Click image to enlarge.
 
Figure 5. Group photo of a portion of the 65 people involved in the project in the summer of 2004. Included are professors, teachers, college students taking a summer class, and a large group of young student scientists with their teachers from Trinity Christian Academy in Dallas who joined the excavation for three days last summer. Photograph by Justin Woods, 2004. Click image to enlarge.
 
Figure 6. Lunch at the dig site. Lunch time provides participants the opportunity to share discoveries and experiences over food. The shelter behind the group provides relief from the weather on infrequent rainy days and protection from the elements for equipment. Although the shelter covers a portion of the bone bed, excavation under the shelter is reserved for inclement weather. Photograph by Justin Woods, June 2004. Click image to enlarge.
 
Figure 7. A group of college students in the main quarry working down to the bones with dental tools, awls and brushes. Shown in the lower center of the photo is a large femur (upper leg bone) adjacent to a pubis (part of the hip) from the duckbilled dinosaur Edmontosaurus. Bones from Triceratops and Nanotyrannus as well as Tyrannosaurus, Pachycephalosaurus and other Upper Cretaceous dinosaurs are commonly encountered in the quarries. Photograph by Justin Woods, June 2002. Click image to enlarge.
 
   
Copyright 2005 by Society for Amateur Scientists