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RT @cognitivepolicy: This morning I'm reading about the geologic and biological history of the Americas when north and south collided to fo…
RT @cognitivepolicy: This morning I'm reading about the geologic and biological history of the Americas when north and south collided to fo…
This morning I'm reading about the geologic and biological history of the Americas when north and south collided to form the Isthmus of Panama. This brought the greatest exchange of land species in the history of Earth. Fascinating! Follow along here: h