Poem about slurping, and other subjects

At first life was a primal soup
That sucked and slopped and slurped;
Then out of this gobsmacking gloop
There crawled a fish that burped.

A billion species rose and fell
In some amount of time;
They glopped and bubbled up and back
Into the primal slime.

One half of these were vegetables –
They erped out oxygen.
The other half were animals –
They belched out CO2 again.

Though muddy, Mother Nature has
A balance to her parts:
The moral to this story is
You’re breathing in tree farts.