Dr. Josh Samuels demonstrates how he removes a fossil from the rock to bring it into the lab for study. This fossil, discovered on 10/21/10, is the humerus (upper arm) of a Pogonodon, a jaguar-sized cat-like predator that lived 29-30 million years ago.
Jennifer Cavin, fossil preparator, describes the process for preparing the Pogonodon humerus from episode one for study and display once it has been brought into the lab from the field.
Jennifer Cavin, fossil preparator for John Day Fossil Beds National Monument, describes the process for completing preparation of the Pogonodon humerus from episode one.
>> JENNIFER: The last time you saw this fossil it was still completely covered in rock. After 40 hours of slowly
taking down the matrix you can see that the bone is now completely uncovered. The next step is to take it out of its
plaster jacket. I can tell already that there’s a large crack running all the way through the bone here so these two
pieces will probably definitely come off separately, and right here there’s a little bit of bone broken off, but
it’s okay if they break because the next step will be to glue it all back together. It’s a little stuck to the
toilet paper, but that’s easy to remove. Make sure to get all the little fragments.
[Sound of ripping]
>> JENNIFER: Okay, the next step will be to clean it up a little bit more and using a polyvinyl acetate glue, glue
the two pieces back together and then the original humeral head that was found in the field, that fell off in the
field will also be glued back on together, you can see we'll have a fairly complete bone.
[TP Scraping]
[sound of light picking]
>>JENNIFER: I just spent the last four hours deep cleaning the bone a little bit more after we took it out of the
jacket. As you can see there are three pieces to the bone, the one break is a very, is a very clean break and the
pieces will fit right back together with no distortion at all. This is the break that was enclosed in the rock so
it’s a very clean break, the, a, the second break was the break that was exposed to the surface and as you can see
there’s just a lot of dirt still in there that contains some bone but to remove it you’d lose the bone, and a, so
this break I’m probably not going to be able to repair because there’s just some bone missing. As a size comparison to the Pogonodon hummers you can see this modern cougar humerus that I’m holding here you can see it’s a much more robust humerus on the pogonodon. Ok, now we're going to glue the good break back together. I’m using polyvinyl acetate which is just a plastic polymer that’s dissolved in acetone. I apply the glue to one side of
the bone then I touch it to where it’s going to go to get glue on both sides of the bone, it creates a stronger bond
and then you wait till it dries. So a couple hours from now, at least, I’d say is when you want to handle the bone
next. Instead of holding it you can embed it in a sand box, this is one we kinda made here, and now we wait.
On July 30, 2011, park paleontologists teamed up with fire personnel from Malheur National Forest to airlift via helicopter a large, 28.8 million year old three-toed horse, called Miohippus, from the face of Sheep Rock.
