Transcript:

Fossils Touchstones to the PastWhen I was growing up, my father used to take me on fossil hunts. It was often a magical experience to uncover evidence of ancient life forms right underneath your feet. Recently I learned that there are still fossils to be found right in my neighborhood. I'm Jim Metzner and this is the Pulse of the Planet.Schimmrich: What you're looking at here - this ledge of rock, is actually a reef, similar to modern day coral reefs. You'll notice that there are these fossils that look like links in a chain. It's actually called chain coral. Steve Schimmrich is a professor of geology and earth sciences at SUNY Ulster Community College. He took me on a mini fossil hunting expedition not far from where I live in upstate New York.Schimmrich: The rock itself is similar to limestone. It represents sediment on an ancient warm shallow sea floor - close to 400 million years old, twice as far back as when the dinosaurs were walking around. The most advanced form of life on earth at the time - all in the oceans - were early fish.A fossil is essentially the remains of some form of ancient life, either the entire body of the organism or a part of it. In some cases even the trace of an organism, its trackway, for example.The material when the organism was living was composition of calcium carbonate or the mineral calcite, but after it gets buried in the sediment and groundwater moves through it, there are various processes that can replace that with a harder more resistant mineral. Typically that mineral is quartz or silica, another common mineral, but much harder and more resistant to erosion than the surrounding rock is.We'll hear more about finding fossils in future programs. Pulse of the Planet is made possible in part by Virginia Tech, inventing the future through a hands on approach to education and research.