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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.

Even from space, you can see

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