The Coming of Life
The Proterozoic Era
First life appears in the water in the form
of bacteria, blue-green algae purifies the
atmosphere and creates the ozone layer.
The oceans are filled with calcium. The
radiorians (one celled animals) appear.
They eat the calcium from the ocean water
and develop hard coverings, which protects
their soft bodies. The sponges develop.
They also utilize the calcium to build the
"houses" that they live in, that is their
exo-skeletons. So these creatures
help to purify the oceans.
But still there is too much calcium in
the water so the corals evolve. Together all
these sea creatures help to keep the calcium
balanced in the oceans. They keep the
ocean pure so that life can exist.
Pinegreenwoods Montessori
