Richard Dawkins: Diatoms: The Evolution of a New Species - Nebraska Vignettes #5
Richard Dawkins explains how microscopic algae called Diatoms uniquely evolved in Yellowstone Lake. Download Quicktime version (720p HD): http://cdn.cloudfiles.mosso.com/c116791/Diatoms3.mov...
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- This is the skeleton of a diatom. It’s a microscopic plant, an alga. Lives in lakes, in pond scum, and the skeleton is a beautiful, intricate, lacy structure, and the beauty of it is that it fossilizes. If you look in ponds, widespread over the United States, you’ll find a diatom called Stephanodiscus niagarae. It’s very, very common. But if you look in Yellowstone lake, you’ll find a unique species which is only found there, Stephanodiscus yellowstonensis. If you take a core sample from the mud below the lake, underneath the lake, you find Stephanodiscus niagarae at 14,000 years old. 14,000 years ago, the climate was cold and wet, and the diatoms were just the same as the diatoms in the rest of the country. But as you look in more and ...
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- This is the skeleton of a diatom. It’s a microscopic plant, an alga. Lives in lakes, in pond scum, and the skeleton is a beautiful, intricate, lacy structure, and the beauty of it is that it fossilizes. If you look in ponds, widespread over the United States, you’ll find a diatom called Stephanodiscus niagarae. It’s very, very common. But if you look in Yellowstone lake, you’ll find a unique species which is only found there, Stephanodiscus yellowstonensis. If you take a core sample from the mud below the lake, underneath the lake, you find Stephanodiscus niagarae at 14,000 years old. 14,000 years ago, the climate was cold and wet, and the diatoms were just the same as the diatoms in the rest of the country. But as you look in more and ...
