Marine Extinction
People have suggested acid rain, they have suggested global darkness
and global cooling, there are pretty good reasons to rule out acid
rain or global cooling as causes of marine extinctions, they basicly stem from the
size of the ocean, the ocean has such a tremendous
resovoir of heat and acid buffering material that acid rain and global cooling are
unlikely direct causes of marine extinction, global
darkness on the other hand would be a very easy way to drive marine organisms to
extinction, if you basicly turn out the lights over
the entire planet, then all of the plankton in the oceans run out of their primary
energy source, because when you shut off the sunlight,
you shut off the ability for phytoplankton to grow and reproduce, when those
plankton die still larger animals have nothing else to feed
on and the whole eco system would basicly collapse. It only took six months of
darkness to make the dominant marine animals extinct.
Ammonites had been on earth for over 300 million years, and had gone through all
kinds of waxing and waining of diversity with other mass
extinctions and they had allways come back, this is the only mass extinction from
which they did not come back.
My Ammonite may be more than 100 million years old !!
Ring of Cenotes