rhinoceros, over time..........

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Yesterday in Emergence of Life, we heard about the impact of the meteor or comet which struck the earth on the edge of Mexico's Yucatan peninsula about 65,000,000 years ago.  I knew it was big, and knew it was bad, but don't remember hearing, before, that if you took all of the current nuclear arsenal on earth, and exploded it all at once, the KT impact was 100,000,000 (one hundred million) times stronger.

My.  Unimaginable.............

We heard about the "jetting" compressed-air wave that was as hot as the surface of the sun and moved at supersonic speed.  We heard about the amount of the planet's surface that was vaporized and/or blown high into the atmosphere (some of it blown into space).  We heard about the tsunami that was over a kilometer high.......  Many of the effects from this impact were still affecting life on Earth decades after the impact..........

85% of species went extinct as a result of this cataclysm......

Before the impact, diapsids (including dinos) ruled the earth.  Most of them died out.  This left many ecological niches open -- ripe for exploitation by other sorts of animals.  Including mammals.

We are now learning about the rise of the mammals.

There were lots of really big mammals back then.  Look at the rhinoceros, then and now.....






I honor Bruce Fouke, who is teaching Emergence of Life, for making sure this class doesn't violate copyright.  This image is used by the class, and it, like the bird bones/muscles image I showed you earlier, is from Wikimedia Commons.  This one is by DagdaMor.

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