Years ago, I toured a goat farm where the fences formed a boundary between universes.

The grass outside the fences was tall and diverse and colorful and wild.

And the grass inside the fence, I mean, it barely looked like grass anymore, right?

You could barely

call it a field. It had been so over-exploited by the goats who lived there. And so, of course,

the one thing these goats wanted to do was to get to the good stuff. They wanted that long

buffet-style grass.

And so even in the brief time I was there,

I personally saw multiple goats escape

and start packing down this wild grass as fast as they could

because they knew they only had like a minute

before they'd get wrangled back in.

If you understand why these goats wanted out, you understand why life left the ocean.

The first vertebrate animals evolved in the ocean about 450 million years ago. And for about a hundred million years

after their emergence, really an unfathomable length of time, they remained in the ocean.

Eventually, as animals diversified to fill the many underwater niches, and as the ecosystems

of the depths matured, the wealth of the ocean dwindled.

It became a rather competitive market.

The grass began to look a little greener on the other side.

On land, there was ample space, ample food in the form of invertebrate and plant life, and there

was little to no competition for it. The story is way more complicated and mysterious than this.

Obviously, something must have changed to allow this cost-benefit equation to become

...