Research website of Dr Gilbert Price

Archives for May 1, 2013

Keeping your hands clean in the field

Euryzygoma premaxilla fossil from Chinchilla showing three incisor teeth

Euryzygoma premaxilla fossil from Chinchilla showing three incisor teeth

The life of a palaeontologist isn’t all that glamorous. Most of my time is spent in the office in front of a computer writing reports and grant proposals. One of the things that I really look forward to is getting out in the field and getting my hands dirty. There is nothing quite like being outside in the fresh air and digging up fossils.

I recently ventured out to Chinchilla, southeast Queensland, in search of Pliocene megafauna. I’ve written previously about Chinchilla’s fossil record; in a nutshell, the fossil faunas date to around 3.5 million years and include all the ancient ancestors of the animals of the Quaternary (the time period that we are currently in). Significant amongst the Chinchilla fossil species is a mega-marsupial, the wombat-like Euryzygoma. Not only was it the biggest marsupial of its time, but it probably ranks as number 2 or 3 of all time! Euryzygoma is a real special guy- not only is it the direct ancestor of the Pleistocene Diprotodon, but it is unique in that it is one of the only mammals known on the entire planet that had a skull that it is wider than it is long! This is made possible by it possessing these incredible cheek flanges that are directed outwardly perpendicular to the rest of the skull.

Students protecting the Euryzygoma fossil with wet newspaper

Students protecting the Euryzygoma fossil with wet newspaper

During our time in Chinchilla, I stumbled across a pretty interesting looking Euryzygoma specimen eroding from an ancient river channel. The fossil, although broken, included the front part of the premaxilla (‘snout’) and contained three incisor teeth. It’s definitely a specimen that will contribute significantly to understanding more about how Euryzygoma operated in life.

We were lucky to have several guests join us during our trip- grade 10 students from the Samford Valley Steiner School. They were worked alongside us, not so much on the palaeontology side of things, but were focussed on surveying the region and drafting topographic maps. The maps will be just so important and will allow us to plot in exactly where the fossils come from.

Students cutting up the hessian in anticipation for plastering the fossil

Students cutting up the hessian in anticipation for plastering the fossil

Even though this is one of my favourite bits of doing fieldwork, I spoke to my other colleagues on the trip and we all agreed that it would be a great chance for the students to get their hands dirty and help excavate the new fossil… and they did a tremendous job! Because it is such a delicate specimen, it was necessary that we just didn’t dig the fossil out and throw it in a bag, but rather, we needed to plaster the fossil in a similar way as if you broke your leg. The first step was to dig around the fossil, making sure that we knew where the extremities of the specimen were (only a little part of it was actually exposed), and to ensure that there was enough area for the plastering work. The students then soaked sheets of newspaper and wrapped them around the fossil. There are a couple of reasons for doing this- firstly it will cushion the specimen once the jacket is finally removed; and secondly, it protects the specimen from the plaster (plaster is notoriously sticky stuff and could actually wreck the specimen if it is applied to it directly).

Steiner School students plastering the Euryzygoma fossil

Steiner School students plastering the Euryzygoma fossil

While some of the students did this part, others busily cut up strips of hessian and mixed the plaster. Then it was time to get messy! The students soaked the hessian strips in the plaster and then wrapped them around the specimen. The idea is that the hessian reinforces the plaster much like steel reinforces concrete. When the plaster eventually dried, we had a super strong cast around the specimen. We left it for a few hours to harden and then we dug under it, rolled it over, and it was ready to go. Because the students undertook the entire task, I didn’t have to get my hands dirty at all! I think that they got a lot out of it- I mean, it’s not every day that one gets to make a plaster jacket for a fossil of an extinct mega-marsupial!

The specimen travelled back with us to The University of Queensland and is now ready for additional preparation work. Although, I was thinking about it the other day- this might be another great opportunity for kids to do the prep job at an upcoming Open Day at UQ. At this rate, I might not have to clean out dirt from under my fingernails ever again!