Q&A with Alex Brannick: What's it like to dig out a T. rex?

Wilson Lab members with the T. rex specimen. Left to right: Dr. Dave DeMar,
Luke Weaver, Alex Brannick, Brody Hovatter. Photo credit: Dave DeMar
What’s the workday for a fossil researcher – a paleontologist? Recently, a group of paleontologists in UW Biology discovered and partially excavated a fossil of the famous meat-eating dinosaur, Tyrannosaurus rex. Here, Alex Brannick, Ph.D. candidate and scientist on the scene, shares what it was like to work on this project in the field:

What research were you doing at the Hell Creek Formation, where the T. rex fossil was found?
My research surrounds studying the morphology and evolution of Cretaceous metatherian mammals (a group of mammals that includes modern marsupials). Fossils (mostly teeth) of the animals that I am interested in can be found in the Hell Creek Formation of Montana. I was also part of a surveying project in the beginning of the field season. So, not directly connected to the T. rex. However, Dr. Greg Wilson (my advisor) and his crew are part of larger project that includes many different areas of paleontology and geology, including collecting dinosaur specimens.

Did the field crew expect to find a T. rex?
Not at all! To find a T. rex is pretty rare, and it's even more uncommon to find a reasonably intact skull (ours will be only the 15th found in the world!)

What is special about this particular fossil set?
The Tufts-Love Rex is special in that we have the skull and lower jaw, both with teeth, which is rare (and exciting!) to find. Additionally, we have associated ribs, including neck (cervical), chest (thoracic), and belly (gastralia) ribs, vertebrae, and a pelvis so far. Based on estimated skull length, this T. rex is about 85% the size of Sue, one of the largest T. rex specimens ever found, currently housed at the Field Museum in Chicago. So, our specimen is Big- with a capital B (estimated to be around 40ft long!). Because time is limited during the field season, we had to leave the site knowing that there is still more bone going into the hill. We won't know how complete this specimen is (i.e. if there are associated arms and/or legs) until we are able to explore the area further in upcoming field seasons.

How long did it take to excavate the head? What was the process?
Personally, I spent about a week helping excavate, jacket, and move the specimen on to the truck that transported it back to Seattle. However, other crew members, including Dr. Dave DeMar (Wilson Lab alum and current postdoc), spent over a month at this site. What many people may not realize is how much sediment actually needed to be moved in order to get to the specimen. The T. rex was located at the bottom of a butte, and much of that rock had to be moved out of the way to safely get to the specimen. By rough calculation, about 20 tons of sediment overburden was moved. And all of that it was all done by crew members using shovels, a jackhammer, a wheelbarrow, pick axes, trowels, feed scoops, and brute strength. A LOT of work was done to even get close to the rex. Once the crew was at a level where they thought bone was (based on the level where they saw bone spilling out on the surface), the crew then started to peel away the sediment in much smaller layers using mostly small hand tools, including awls and oyster shuckers.

Check out the size of the skull jacket and rib jacket!
Photo credit: Dave DeMar
Help us visualize a typical day of excavation.
A typical day out with our field crew starts with 6am breakfast of cereal and coffee-early, I know, but you get used to it. We pack our lunch right after breakfast, which is usually a sandwich and some side snacks like chips, apples, and fruit snacks. Depending on which camp you were staying at and travel time, we would try to be at the site between 8 and 9am. We try to start work as early as possible because Montana summer afternoons can be scorchers. There had to be some flexibility on what was going on each day because the size of the crew and the tasks that needed to be completed fluctuated as the excavation continued. Usually people were given certain tasks or a specific area to work on for a day, but that could change the next day.

Everybody took turns and helped each other out. We didn't prep the specimens out too much in the field, leaving quite a bit of rock surrounding the bone, in order to protect the bones during transport back to the lab. In the lab is where preparators will more delicately etch away the rock to expose all of the bone.

How did the rex get to the Burke Museum?
Once a section of bone was ready to be transported, we first encase that section of rock and bone in a protective jacket, composed of burlap and plaster. Plastering is a lot of fun! After the jacket has set and is ready to move, we can move them to the truck or trailer and they can be brought back. Some jackets are small and one person can carry them, but in the case of the T. rex skull, the entire jacket weighed over 2,500 lbs (more likely about 3,500 lbs)! A local rancher helped us moved the larger jackets we had at the site using his tractor and hay bale lifter. Those jackets were placed on a flatbed truck, which then made the long drive back to the Burke.

Once back at the Burke museum, we had help from the Skanska construction team in moving the larger jackets, including the skull jacket. They were able to use their forklift to move the jackets on to a movable palette on the Burke loading dock. From there, they were brought into the collections, where Bruce Crowley and other Burke preparators will open the jackets and begin prepping the specimens. The skull jacket is on display in the Burke museum (until Oct. 2nd) before preparation begins, if anybody would like to check it out!

What information can we gain from analyzing this specimen?
It depends on what else there is of the specimen. Other researchers may come out to look at the Tufts-love Rex to address their own specific research questions, especially because obtaining complete skulls with associated postcrania is rare. The specimen may tell us more about individual morphological variation in T. rex or how that morphology changes during ontogeny (the age of this rex will likely be determined with further research). We know where it falls in time and space relative to the K-Pg boundary so it could potentially be useful for something related to that as well.
Lots of sediment had to be removed. Photo credit: Dave DeMar

Was the DIG field school involved in any way?
Yes! During the second day of the DIG field school we took 33 teachers from all over the country to this amazing site for a once in a lifetime opportunity in helping with the excavation of a T. rex. All of the teachers were really excited, especially since they will be able to bring that experience back to their classrooms.

How would a volunteer interested in future digs get involved?
This entire project and the T. rex specimen is the result of a huge collaborative effort from the many people involved, including many volunteers. It was a ton of fun! If anybody, such as undergrads, would like to volunteer and help with future digs, they should contact the current Wilson Lab manager, Brody Hovatter (bthov13 [at] uw.edu).

What are your future plans? Other comments?
I hope to return to Montana next year for more fieldwork, but I'm not sure yet if I will be back at the rex site. If I am able to go back, I'd love to! I was really excited to be a part of such a big discovery and I am thankful I had the opportunity to be a part of its excavation!

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