How Did Life Begin?

In this short video explainer, Universe Today publisher Fraser Cain investigates the mystery of abiogenesis. How did we get from non-life to life on Earth?

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No answers today, only a question. But it's one of the most interesting and meaningful questions we can possibly ask.

Where does life come from?

How did we get from no life on Earth, to the rich abundance we see today?

Charles Darwin first published our modern theories of evolution- that all life on Earth is related; adapting and changing over time.

Look at any two creatures on Earth and you can trace them back to a common ancestor.

Humans and chimpanzees share a common ancestor from at least 7 million years ago.

Trace back far enough, and you're related to the first mammal who lived 220 million years ago.

In fact, you and bacteria can trace a family member who lived billions of years ago.

Keep going back, and you reach the oldest evidence of life on Earth, about 3.9 billion years ago.

But that's as far as evolution can take us.

The Earth has been around for 4.5 billion years, and those early years were completely hostile to life.

The early atmosphere was toxic, and a constant asteroid bombardment churned the landscape into a worldwide ocean of molten rock.

As soon as the environment settled down to be relatively habitable, life appeared.

Just half a billion years beyond the formation of the Earth.

So how did life make the jump from raw chemicals to the evolutionary process we see today?

The term for this mystery is abiogenesis and scientists are working on several theories to explain it.

One of the first clues is amino acids, the building blocks of life.

In 1953, Stanley Miller and Harold Urey demonstrated that amino acids could form naturally in the environment of the early Earth.

They replicated the atmosphere and chemicals present, and then used electric sparks to simulate lightning strikes.

Amazingly, they found a variety of amino acids in the resulting primordial soup.

Other scientists replicated the experiment, even changing the atmospheric conditions to match other models of the early Earth.

Instead of water, methane, ammonia and hydrogen, they wondered what would happen if the atmosphere contained hydrogen sulfide and sulfur dioxide from volcanic eruptions.

Environments around volcanic vents at the bottom of the ocean might have been the perfect places to get life started, introducing heavier metals like iron and zinc.

Perhaps ultraviolet rays from the younger, more volatile Sun, or abundant radiation from natural uranium deposits played a role in pushing life forward into an evolutionary process.

What if life didn't start on Earth at all?

What if the building blocks came from space, drifting through the cosmos for millions of years.

Astronomers have discovered amino acids in comets, and even alcohol floating in distant clouds of gas and dust

Maybe it wasn't the organic chemicals that came first, but the process of self organization.

There are examples of inorganic chemicals and metals that can organize themselves under the right conditions.

The process of metabolism came first, and then organic chemicals adopted this process.

It's even possible that life formed multiple times on Earth in different eras.

Although all life as we know it is related, there could be a shadow ecosystem of microbial life forms in our soil or oceans which is completely alien to us.

So how did life get here? We just don't know.

Maybe we'll discover life on other worlds and that will give us a clue, or maybe scientists will create an experiment that finally replicates the jump from non-life to life.

We may never discover the answer.

[frasercain]

It's perfectly fine to say, "we don't know". If we knew the answer to everything, we'd stop searching. And that's why made up stories are so dangerous. They stop us from searching for the real answers.

[JosephRichardson_jwrmm]

I think the very best questions lack answers. Each time we ask, we learn a little about ourselves--and so we're better for the asking.

Thanks, Fraser. I really enjoy these.

[frasercain]

Sorry, but creationism doesn't qualify as a legitimate theory to explain the origin of life.

[frasercain]

Exactly. Evolution shows us that all life on Earth is related and changing over time. That means you can trace it all back to a common ancestor. But Evolution doesn't provide an explanation for what came before.

It's the same thing as the Big Bang. The theory nicely explains the Universe as we see it, and we know it all started as a single point 13.8 billion years ago. It doesn't say what came before. That'll have to come from a different theory.

[frasercain]

Sometimes just the question alone is fascinating.

[frasercain]

I'll probably cover Before the Big Bang at some point, but it'll sound a lot like this video.

[jirehguy]

Thx you really help me with my questions about the universe.

[jeranism]

 "Take any two animals on Earth and you can trace them back to a common ancestor."  FOLLOWED BY "Humans and chimps have a common ancestor that dates back 7, 000, 000 years. So then, can you trace the common ancestor of humans and rats? or humans and ants? So in 7 million years we went from chimp to human and yet in the previous 493 million years we went from amoeba to chimp? Fill me in

[frasercain]

Exactly, life could have formed multiple times in the history of our planet. Which is the concept of why we could have a shadow ecosystem.

[Molly-vnhf]

If you make a video on Halloween, you should wear a planet costume. (If you haven't already, I'm kind of new to your channel)

[Stickings]

I was told that the problem of Abiogenesis is the Achilles heel to Evolutionists and the theory of evolution, with many supporters of evolution ducking the question. I was also taught that all experiments have shown life comes from life, and that of it's kind.

A while ago though I heard that some were exploring the RNA route, any updates on that research?

[Wa]

Evolution is one thing, abiogenesis is something completely different. Evolution only tells what happens after life is already present.

[tomcmlee]

We may never know how life began. But according to latest research it may have begun (arxiv:1304.3381) as far back as 9 billion years ago.

[RiotHouseLP]

Amino acids are found at the bottom of the ocean near hydrothermal vents as well. Which would have an even higher chance of being the origin of life.

[lukabotic]

Now I feel sooo guilty for chlorinating that pool in a rental property when I was 18. What have I done. Perhaps Q can snap his fingers in that CTRL+Z way he does.

[RPKGameVids]

It's alcohol, Jim, just as we know it.

[elmile]

My question is why. Why do amimno acids or whatever transitions to life?

[RotlochStudio]

Do you know what happened before The Big Bang? Do you have some theories, or video in your channel? And what if our universe is part of some bigger organism :)

[Stickings]

But you can not have evolution without Abiogenesis having first occured

[TheGoldenPhat]

I honestly think that maybe one day mars had living creatures that once lived on mars and roamed around but what I think is that a meotor or some giant thing crashed or some hit it that made some of the necessary basic ingrediants travel to this lifeless earth and it eventually fertilized it and made one of the first cells which made pretty much the ingrediants to make anything happen like the first dirst or soil on the ground and would then eventually make the first living walking creatures that would then roam the earth just like it did with mars, maybe if this is wrong maybe some meateor containing the basic ingrdiants from unknown regions of space crashed into the earth like my mars theory but we all still come to wonder where was this coming from.