Tuesday, July 8, 2014

An environment recovers



The fossil layer at Ashfall is only about three feet deep. Above that, however, is anywhere from three to seven more feet of ash where it continued to be blown into the watering hole for about a year after the ash first fell. In this time, there are no fossils, there are no signs of life of any kind. The area looked about like the desert in a drought or Nebraska after the worst snow storm of the century.

 But like after any other natural disaster, ecology eventually took over and the area was able to rebound. It took a little help from the right geological circumstances, though.

For example, around that time the glaciers started becoming a little more active and the river nearest to here changed course, putting Ashfall right in its flood plain and thus depositing layer after layer of sand and soil that was much, much more fertile than ash. Then as time passed, the plants came back, and eventually near the top we are once again able to find the fragmented remains of every animal in the ash bed and even some that are only present from before the ash fell.


But before animals can come back, the plants had to return. And we actually find their roots in the side of the hill, still in the sand where they grew millions of years ago.

 Side note: in the layer below the ash, we also find plant root fossils, but nothing still in situ. We find little calcifications that formed around the roots and preserved, and we find these a lot when we sort through the material for microfossils.

 But back to the recovery layer. This, plus the animal fossils we find in that layer, make it so that, to me, Ashfall doesn't just record a tragedy, but a success story. The world will be fine after a disaster. It just may not always look exactly the same (though for once, here, it did.)

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My Story (Very briefly...)

Lots of people claim that they wanted to be paleontologists at the age of 3. So did I. The problem is, I never really grew out of it. My third birthday party had dinosaurs. Everywhere. I grew up digging in fossil dirt from Aurora, NC, looking for coral and shark teeth. I practically lived at my local science museums (and still do, only now I get to do research, fossil preparation, and work in collections!) When local paleontologists discovered a dinosaur with a "fossilized heart" (no longer considered such) when I was little, I got to meet the man who led the work. And then, years later a dinosaur bone with soft tissue turned up. I was officially hooked.
No longer was I dreaming about dinosaurs. I was actively pursuing the science behind prehistoric creatures. I didn't want to read about it, I wanted in on the action. So I started working at the museum, and finally going on my own adventures. And thus, I needed a place to share them and maybe inspire others the way I was inspired. I have gone from watching fossils be prepared from one side of the glass at the museum to working on them on the inside of the glass. I am a student working toward my goal. I can finally start to call myself a paleontologist.