Wednesday, October 7, 2009

North Dakota Dinosaur Dig: Part 4

Posted by Kirk
(Be sure to read part 1, part 2 and part 3 first)

Ah, Thursday and Friday. We're almost at the end of our journey. I'm not posting anything about Friday as it was just our drive home.

After our rain day Wednesday we were itching to get back out in the field on Thursday.

We had a fantastic day. I drank over four liters of water in the field and I was still thirsty. I can see how if you were to run out of water out there it could be bad very quickly. It wasn't even that hot. The week before we arrived they were having temperatures in the 100s.

The arrow on the left shows the view of our van from where we ate lunch Thursday. That white splotch is an 18 foot long 15 passenger van.

Here's the same photo uncropped for comparison. Can you pick out the van? We hiked though this basin and stopped atop this butte for lunch. The spot we're sitting in is relatively flat as they removed a triceratops from this site a few years ago. There were some bone scraps left behind and little pieces of plaster from making a field jacket for the beast. Can you imagine carrying the dinosaur back to where the van is in this photo?

I sometimes read complaints that the fossil record is incomplete. This sometimes comes from those who oppose the theory of evolution. They argue that there has been plenty of time for scientists to find all the fossils they need and transitional forms have not been found. First of all, EVERY fossil is a transitional form since evolution is a gradual process. The "no transitional forms" argument is completely bogus and anyone who uses it shows a gross misunderstanding of what evolution is and how it works.

Second, people who complain in gaps in the fossil record need to go on a dig to appreciate how hard it is to get these finds out of the field. The dinosaurs are embedded in hard rock. First you have to find one, then you have to have the time and physical and financial resources to spend a year or more getting it out of the ground. This often involves taking off layers of stone many feet thick, one exacto blade scrape at a time. Imagine scraping away a whole hillside of hard rock with a dull exacto blade in blazing heat and humidity. Once you finally uncover the dinosaur you have to make a plaster field jacket and then transport it back to a lab (which in some cases means building new roads just to reach the site) It doesn't end there, you have to spend possibly years cleaning and assembling it which takes more money. Once you see the vastness on an area like this and then realize there are essentially two or three people with a shoestring budget trying to find the treasures that have been battered by erosion and covered over for 65 million years and you begin to see how it may take some time to fill in our gaps in understanding. This is still a very young science and there are many millions of critters still waiting to be dug up.

Thursday was all about microsites. Microsites are locations rich in animal parts but not necessarily complete animals. These were often little backwater areas long rivers. As animals died in or near the river their remains broke apart and were carried downstream. These parts all collected in slow spots and when scientists find these today the sites are very valuable scientifically. It may not seem as interesting if there are no complete animals at a site but a complete animal doesn't give us much information about the ecology of the place it lived. In microsites we get a cross section of animal life and that can tell us what types of animals lived together in the same area. Working a microsite means we spent a good part of the day sitting on the ground moving painstakingly forward looking for teeth, turtle shell pieces, fish scales and small limb bones. At the third site of the day I found two dromeosaur teeth but stupidly didn't take a picture. This particular site was still of scientific interest so we couldn't keep anything. It was similar to the teeth pictured here.

In the photo to the left we're heading home for dinner on Thursday. You can click on it (or any photo on the blog) to view a bigger image. The barbed wire fence on the left hand side of the picture marks the border with Montana. I could have spent many more hours in the field I was having so much fun. I inhaled a huge dinner of nachos and encheladas after the hour and thirty minute van trip back to Marmarth. I was very excited to not have hot dish.

I had a great time on the trip and I can't wait to go on another dig. I'll have to though. We need to line up some funding as this was an expensive summer camp to offer. In the mean time I'll have to content myself hunting down an relatively complete ordovician period cephalopod along the banks of the Mississippi or perhaps a complete crinoid. That should keep me busy.