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Even from space, you can see
that the planet Earth is full of life.
When you take a closer look,
you'll discover a delicate
balance of millions of different life forms
co-existing, and relying on each other
to survive.
But what if these aren't all unique
individual organisms?
What if they're all just extensions
of one superorganism?
The Earth.
Think of the Earth as being like a human body.
When our body starts to overheat,
it has its own perspiration system to help
regulate its temperature and cool down.
When Earth starts to overheat,
it has its own system of plant and animal life
to regulate its atmosphere and control the temperature.
But now our planet is heating up at a pace
that is beyond its abilities to keep fixing itself,
and that's due to us.
Which begs the question:
are we a part of Earth's regulatory system?
Or are we a disease that has come to disrupt it?
Today we're going to do things a little differently.
Instead of our usual approach of
looking at what would happen if the Earth became one living organism,
we are going to focus on the theory that it might have been one all along.
The main theory that puts this idea forward is called the Gaia theory,
named after the Greek goddess of Earth.
This theory argues that all living organisms, along with their inorganic surroundings,
adapted and evolved as a collective whole in the form of one giant,
self-regulating system
that keeps checks and balances in place in order for life to survive on Earth.
We know this sounds like the kind of theory that
might have come from the smoky tents of a hippie commune,
but it actually came from a highly accredited scientist named James Lovelock.
He came up with this theory while studying the question of
why Earth's atmosphere is different from what we see on Mars.
Why does our planet have both oxygen and methane,
when Mars has mainly carbon dioxide?
His thinking is that since oxygen comes from plants,
and methane is the result of bacteria,
the Earth is regulating its atmosphere,
providing oxygen to support life,
and methane to help maintain a livable temperature.
Over the years, he found more instances of the Earth basically keeping itself alive,
and his theory started to attract prominent supporters,
such as former U.S. vice president Al Gore.
But despite all the people who supported the Gaia theory,
there were far more critics who dismissed it.
One such critic is an evolutionary biologist named Dr. Ford Doolittle
yup, Dr. Doolittle.
He argues that the entire theory violates the scientific method
since it only provides ideas,
but offers no real explanation of exactly how organisms
could act together to maintain a balance of life on Earth.
As it stands now, this is a matter that is still up for debate,
but the opponents of the Gaia theory probably hold the edge.
If nothing else, the Gaia theory can at least be beneficial
to our society as an ideal to encourage people to take better care of our planet.
If we look at ourselves as being a part of our planet's regulatory system,
then we might choose to make more conscious decisions to aid that system,
rather than to destroy it.
Maybe one day we'll look back at the Gaia theory
as the beginning of a better understanding of our role on Earth,
but that's a topic for another WHAT IF.