Did the Emergence of the Continents Lead to Animal
This is Science Today. The emergence of continents
almost a billion years ago may help explain the
origins of animal life. A new theory by geologist
Eldridge Moores of the University of California,
Davis says the continents surfaced more quickly
than is commonly thought, and the results were dramatic.
If you drained water off the continents, then you
start getting this tremendous continental effect which
would invigorate ocean circulation and that would
stir up nutrients that happen to be in the oceans
and you'd be eroding stuff that's coming off the continent.
These environmental changes would have added oxygen
to the atmosphere, which was a precondition for animal
The oxygen content of the atmosphere went from a fairly
low level of two percent to the present twenty percent.
And it's that rise in oxygen that has made possible
the development of animals. We wouldn't be here today
if it wasn't for the fact that we have an atmosphere
that's out of equilibrium.
For Science Today, I'm Larissa Branin.