Thursday, July 25, 2013

Archeo and Paleo - you know, those dirt-diggers



When I came here in late April I really had no idea of the difference between archeology and paleontology. I feel kind of stupid to even admit that, but there you are. It also didn’t help, that when I met the guys that head the two departments, I learned that both their names are Bill. I need things mapped out distinctly and having two guys named Bill who dig in the dirt didn’t help to clarify things. They're even often referred to as "the two Bills." I have a bit of a better grasp on things now, but still stepped in it big time a couple of weeks ago when I was being given a tour of the lab and made the amateur’s mistake of using the word archeology when I was looking at paleontology stuff. Don't ever do that.

On my way to do laundry I saw one of the paleo people, Cathy, sawing away on a chunk of dirt encased in plaster. 


Not one to miss an opportunity to see and learn something new, and loving behind-the-scenes activity, I dumped the laundry in the machine and wandered back to see what was what. Cathy is a preparator, someone who cleans up fossils from the matrix (the dirt) surrounding them. What she’s doing here is releasing a specimen from the dirt that it’s been encased in for a couple hundred million years. Seriously. 225 million years.

When the paleontologists find something, they dig outside of what they estimate the margins of the specimen are. Then they pour in plaster to encase the bottom of it. Once it’s dried it’s taken from the ground and the top and sides are enclosed as well, all with the intention of stabilizing the specimen. Cathy has already removed the top and is systematically, slowly, and carefully taking off the plaster, in order not to saw into the fossil. I know nothing but I know this wouldn't be good. 

This is what another jacket looks like before she does any work on it. (By the way, any errors in reporting the process or anything else the paleo people do are mine alone. Cathy knows what she’s talking about and I do not.)




She and the others catch the matrix and dump it in a bucket for later sorting. They can look at a lump of something and identify it as some kind of bone and all I would see is a rock. They don’t teach those kinds of things in library school.




Yeah, they’ll sift through these buckets to find the smallest pieces. It would make me nuts but this is what they do. Below is how small some of the pieces can be, where they can fit into vials like these that she’s labeled to know what part of the piece they’re working on they came from.



Below is a partial view of a jacket in the lab that’s been opened and has had so much matrix removed that bones are visible. Cathy pointed out a skull to me, and specifically its eye socket, which I couldn’t see, so she showed me a composite skull of what it was I was supposed to be looking at.




There was a third plaster jacket being worked on inside the lab, and the specimen was partially exposed. Apparently those are vertebrae, once again obvious to the people who do this every day.




The intern sitting across the table from this jacket is working on mold making, where bones (or other objects, I suppose) are embedded in the modeling compound so when that body part is needed to reconstruct a skeleton, a composite part can be made from the mold. Here’s what she’s doing. Now this I can understand. It’s like doing crafts. The intern likened it to being in kindergarten but that’s too far back for me to remember.




And here’s one last look at the work Cathy is doing outside. She was nice enough to ignore my ignorance about practically everything and pointed out one more item of interest. It’s the bullet-shaped object at near dead center of the photo. It’s a coprolite. Fossilized poop. Now, truly, how cool is that? It's 225 million years old!




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Thought of the day:

It is obvious that we can no more explain a passion to a person who has never experienced it than we can explain light to the blind. (T.S. Eliot)