The other day I went out to a pasture about as far away from my house that I can go on my own property to pick up an ATV left behind for some fencing activity the day before. I hitched a ride to the site with Ray Williams and picked up the ATV around 8AM. I figured while I was out there, I would check out a hill with just a little sandstone outcropping near the top that I had never been on before. I knew it was in the right part of the geologic column for there to be dinosaur material possibly present. Usually I just get exercise when I undertake such a stair climbing expedition up a large hill. I knew this was different right away.
Upon starting up the hill, I noticed that there were a few light tan chunky dinosaur bone fragments (pretty small) in just the soil at the foot of the hill. That is unusual I thought. They always come down hill from above so I slowly worked my way back and forth, carefully noting where they were and were not. That way, I was slowly working toward where they come out from above. Even with this good sign of bone, typically all I get is a few fragments coming out of a layer or perhaps a single big bone weathered into an undoable puzzle by the elements. The difference here is that the pieces instead of tapering off, kept increasing in number right up to the top of the hill. On the top, I did a quick look around and immediately dropped to my knees on a sandy slope strewn with the enameled black scales of the ancient alligator gar fish as well as some pretty nice pieces of dinosaur bone. I immediately saw bone shafts, scales….a piece of fossil turtle shell, wait, a crocodile tooth, wow!!!! a curved sickle shaped tooth from a dromaeosaur (a 6 foot tall, really nightmarish chicken with teeth, a wishbone and sickle claws). I continued to surface collect this spot for an hour and brought back numerous fossils including a dinosaur jaw fragment (no teeth), quite a few nice crocodile teeth, a dozen gastroliths (dinosaur gizzard stones) and a pocket full of other keeper dinosaur things. I did note that there were a few big ant hills on the top though. I was on the site less than an hour.
Next day, I took my son Chris along with a screen sieve and a shovel to sample the work the ants did for me. For your future information, the proper process for sampling red ant hills is as follows, shovel ant mound material into sieve, sieve to suit, immediately bag all material in sieve in zip lock baggies ants and all, transfer material to wife’s favorite microwave safe covered dish, 120 seconds per 5 pounds of sediment on high will kill any imbedded ants. (Run if wife finds out about the dish!) Do not, I repeat, do not try to examine material in the sieve on site after properly agitating ants. Formic acid is pretty irritating under the skin by the way. I must have overslept the day the rest of the class was taught about Wyoming red ant hills in grad school.
The final result was absolutely astounding. These little guys collected over a thousand little teeth for my enjoyment and scientific gratification. Go figure! This mixture of teeth the ants gathers had hundreds of teeth from each of the following groups, the Alligator Gar Pike fish, alligators/crocs, frog hips, vertebra from fish, amphibian jaw fragments, various baby dinosaurs (the ants can’t carry the big teeth which are still in the ground) and most importantly almost 100 Cretaceous fossil mammal teeth. In three years of heavily collecting the Cretaceous Hell Creek Formation for dinosaur fossils, I have only accumulated perhaps 30 Cretaceous Mammal teeth specimens (VERY, VERY RARE THINGS!!). This new site it turns out, is a world class Cretaceous fossil mammal tooth site right here in Powder River County. The academic paleontologists and the museum curators (mammal experts) will be down this summer and there will be papers turned out with these specimens.
I went back and spread a packet of wild rice about the top of the sampled hills to pay back the ants for their diligence and to help them survive the rebuilding of their mounds. The rice grains looked like pupa and down the hole the soldiers dutifully carried their prize. Hopefully they will have the mounds rebuilt by next year.
It may be difficult to write a column every week during the summer field season but finding amazing sites like this one makes it easier. Stay tuned