Monday, April 25, 2011

Creodont - Oxyaenodon dysodus

Last year I spent quite a bit of time in the office doing prep and scheduling while my boss was away. When I finally got back out into the field, the others I was working with seemed to be finding all of the fossils on that first day. I said something like "Man! I've been in the office too long, I've forgotten how to find fossils." Less than 30 seconds later, I found this. I'm not 100% sure, but I think it is Oxyaenodon dysodus. It belongs to a group of extinct carnivorous mammals called Creodonts. Modern carnivorous mammals, Carnivorans, out-competed the Creodonts and drove them to extinction around 8 million years ago.
This is the first Creodont we've found at work (that I'm aware of) and it's in a type of rock in which we don't normally find fossils. The rock fractures very easily and is pretty hard, while the fossils are just a bit softer so that makes it challenging. This was on the surface and when I put all the pieces together it looked like swiss cheese with pieces missing in the middle. I endeavored to fill the gaps with bondo and glue with varying success. Here are photos of the jaws after prep. The pieces of the skull which were associated didn't come out looking so pretty, so I won't post them.
I normally end up preparing other people's finds, and I'm okay with that. This is one of the few fossils I've posted that I can lay claim to finding, and I'm very proud of it.

Sharp teeth,

Dan

Thursday, April 21, 2011

Sphenocoelus intermedius Part 3

So here I am with yet another Sphenocoelus intermedius. I didn't find this one, but I did most of the work collecting it. Also, I was not the only preparator to work on it. Jason began it, Dave continued it, and I finished it.It's missing most of the left side of the back of the skull, but it's got nearly complete nasals which break off so easily. It's also missing all the incisors, canines, and first premolars. Also, the entire top of the head is missing like it's been scalped or something.
Hyperdolichocephalically,

Dan

Friday, April 01, 2011

Amynodon advenus Parts 2 and 3

Both of these skulls are examples of Amynodon advenus. Like the fossil in the previous post, I began them last summer, and finished them this winter, and only just got all my photos for them.
The first one is the third fossil we collected and I prepared from Magic Canyon. It was found by my friend L.J. but almost everyone at work helped to get it out of the field (except me).
End of Day 1Prep Finished
As you can see much of the left side is missing. This was the exposed and weathered portion. The blue in the teeth is bondo. There was a major crack running through this part of the skull, so there is some loss of bone.Here is a nice profile photo from the right side. You can see the nice big canine and overall shape of the head, though there is a little bit of crushing. This was probably a male while the one I posted on last year was probably a female judging on the canine size. The difference between males and females of the same species is called sexual dimorphism.
This second skull was found just off the edge of a well pad during construction by my friend Shaun. We had been in this area before, but for some reason nobody noticed it until Shaun. Good find Shaun!
Before Prep
After Prep
The pink line in the middle is bondo where I broke it in half when I collected it. Oops! I actually broke it a second time during prep, but as I always say, "It's not done unless you break it at least once".
This photo is a view looking at it straight on. You can see there is significant shift. The top is shifted right (left in the photo) relative to the bottom. This is a fairly common trait of many fossils and happens because of intense heat and pressure due to lithification of sediments (sediment becoming rock). Also, though you can't really see it in the photos, the front of both canines has been worn perfectly flat. This is probably due to the upper and lower canines rubbing against one another during life. I haven't seen this in any of the other Amynodons we've collected, though there is still one more that needs to be prepared.

Rhinoceriffic,

Dan

Saniwa cf. ensidens

I began this project way back last July, but wasn't able to finish it until February. I just barely got all my pictures, so here is the post.
This is a pretty amazing specimen. First off, it's a 30% or so complete skeleton which is unusual. Second off, it's a species that hasn't been reported from the Uinta Formation before. It's a varanid (monitor) lizard that is most similar to Saniwa ensidens though it could be a different species. We're not sure yet.
The first photo was taken after my first day of prep, the second photo is the final one. As you can see there is quite a bit of difference. This guy has a leg, pieces of both arms, 25-30 vertebrae from all along the body, a bunch of ribs, 3 pieces of the skull (upper jaw, lower jaw, and back of the head), and a bunch of other tiny bones I wasn't able to identify.
I've submitted an abstract to a professional conference, but still haven't heard back to see if it got accepted.

Best lizards,

Dan

P.S. This is one of the other fossils from Magic Canyon.