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  • Life on Earth.

  • Scientists have been studying it for centuries, creating a timeline from when the first single-cell

  • beings emerged in primordial waters to today when billions of humans populate the surface.

  • But there's one question they've never been able to answer with 100% certainty - how

  • exactly did it begin?

  • Most scientists think it started from a complex chemical reaction in the water of the early

  • Earth.

  • Some argue for a more intelligent hand guiding the process.

  • The only thing that's sure is that no one's sure - and everyone has an opinion.

  • But what if the origin of life on Earth didn't actually come from Earth?

  • Could life on earth be the product of extraterrestrials?

  • So far, we don't have any conclusive proof for or against life outside of Earth.

  • No contact has been made, and no DNA or fossils from other lifeforms has been discovered.

  • But we've only explored a tiny fragment of the universe out there - almost none of

  • it in person - and the odds that countless planets surrounding countless stars would

  • have no other planets capable of supporting life since the Big Bang is pretty slim.

  • And after billions of years of this universe existing, many of those worlds may not exist

  • anymore.

  • Asteroids, comets, and other interstellar phenomena can immediately bring a crushing

  • end to any world's lifeforms - as the dinosaurs found out the hard way.

  • But what if the life from those worlds...didn't stay on those worlds?

  • The hypothesis is panspermia, which claims that not only does life exist throughout the

  • universe, but that it gets carried from world to world by traveling objects like asteroids

  • and comets.

  • The space dust that gets attached to anything traveling through space - even the spaceships

  • that humans send to explore the moon and nearby planets - may have microscopic forms of life

  • in them that travel to other worlds and seed them when they land, creating the building

  • blocks of future life on those worlds.

  • But could anything survive in the cold vacuum of space?

  • Well, we couldn't, and neither could most animals on Earth.

  • But when you look at smaller animals, some survive climates that could kill humans in

  • seconds.

  • The Pompeii Worm lives deep in hydrothermal vents that can reach up to 175 degrees fahrenheit.

  • The Flat Bark Beetle, which lives in some of the coldest climates of North America,

  • produces natural antifreeze chemicals that help it survive the winter and enter into

  • a sort of stasis - smoothly surviving the coldest parts of the winter while we're

  • fighting over the thermostat.

  • Neither of them could survive space - but that's not the case for one microscopic

  • creature.

  • The nameWater Bearprobably creates cute images of an ursine mammal enjoying a

  • bath in the river.

  • But the real thing is much less cuddly - and also less likely to eat you.

  • Also called a Tardigrade, this tiny organism is the only form of life that seems to be

  • able to live anywhere, even in the most extreme conditions.

  • They've been found everywhere from deserts to hot springs, and they may even potentially

  • exist in space - thanks to a crash of a sample from a spaceship on the moon.

  • These tiny multi-legged creatures can dry up and fall into a state that resembles death,

  • but when exposed to water even decades later, they spring back to life.

  • So if life originated from outside Earth, how exactly did it get here?

  • There are a couple of theories of exactly how those building blocks of life arrived

  • on our ancient planet, most of them based around interstellar physics.

  • One theory from a Swedish scientist in 1903 theorizes that the radiation pressure from

  • stars can send particles through space, but this would only work for the smallest particles

  • and many if not all would be killed off by the radiation.

  • But it's possible that alien bacteria or viruses could survive if shielded from UV

  • radiation.

  • The other main theory is that the particles that led to the creation of life were hitchhikers

  • on rocks, coming into contact with Earth when the rocks crash-landed here.

  • While we know how asteroids, comets, and meteors travel through the galaxy, this is under far

  • more extreme conditions than any lifeform has been known to survive - surviving in the

  • vacuum of space for years on end before crash-landing.

  • But there is another theory - that the alien lifeforms didn't come here accidentally.

  • What if the alien life out there was intelligent and advanced enough that they could have sent

  • the building blocks of life towards Earth deliberately?

  • The first possibility of this is accidental transport.

  • On Earth, there have been countless cases of people throwing trash into the water and

  • having it be swept somewhere completely different - often endangering animal life in the process.

  • It's possible that an alien civilization would have been advanced enough to send waste

  • products into space and dump them on an uninhabited world - that thanks to the trace DNA on the

  • waste, evolved into the Earth we know today.

  • But other theories say that the seeding of Earth may be much more deliberate.

  • Directed panspermia is the idea that an alien species created life on Earth via transport

  • of organisms from their world.

  • The idea of a deliberate seeding of the planet sidesteps a lot of the issues with other theories

  • - because the aliens would have been able to shield the samples for their trip, eliminating

  • the threat that the journey through space or the cosmic radiation would kill off the

  • organisms before they ever reached their target.

  • The alien species, if advanced enough to send samples into space, would be able to send

  • them at high speeds that would allow them to reach their destination in a more feasible

  • time.

  • So why would aliens want to seed our planet?

  • The first possible theory is that the aliens were looking to secure and protect life in

  • space by spreading it among a larger area.

  • Even the strongest civilization can be felled by a natural disaster or stray comet, and

  • when life exists on more than one world, it's insured against the whims of the cosmos.

  • Of course, that was 3.5 billion years ago, and the odds are good that any alien civilization

  • that seeded Earth at the dawn of our world would be long gone themselves by now.

  • But what if they weren't?

  • There are many theories about aliens making contact with Earth, but thus far no conclusive

  • proof has been found - regardless of how many people say they were abducted by a flying

  • saucer.

  • But if aliens are out there - and may even have ties to the creation of life on Earth

  • - then why haven't they made contact yet?

  • One theory is that they simply don't want to - they're more than happy to just watch.

  • This is called the Zoo Hypothesis, and it states that we're all essentially living

  • in a giant terrarium.

  • Whatever these aliens are, they have technology far beyond ours and they're perfectly happy

  • watching as our still-primitive planet slowly evolves.

  • If we don't know about their existence, it's because they don't want us to know

  • - yet.

  • So are there any problems with this idea?

  • Just one big one - have you ever tried to get a group of people to agree on anything?

  • Trying to get ten people to agree on one place to eat is hard enough.

  • Imagine how difficult it would be to get an entire civilization to agree to keep a secret

  • forever without any of them breaking the code of silence and broadcasting their existence

  • to ourhuman zoo”.

  • It would have had to last millions of years of humans and their ancestors existing, and

  • likely countless generations of the aliens not breaking their own protocol.

  • That's why many people say the Zoo hypothesis resembles creationism and religious theory

  • more than panspermia.

  • But have the aliens truly maintained a hands-off approach all this time?

  • A popular idea - but maybe not so popular among scientists - is that Earth has been

  • visited repeatedly by advanced alien civilizations that may have interacted with humans before

  • recorded history.

  • Called the Ancient Astronauts theory, it often has ties to various religions - after all,

  • how many religious texts refer to powerful and mysterious beings descending from the

  • heavens and performing miracles?

  • But is there any evidence of these interstellar visits?

  • If you watch a program called Ancient Aliens - a lot!

  • This popular documentary-style series looks at evidence of alien interactions with humans,

  • with a particular focus on early civilizations and the idea that certain technology and buildings

  • couldn't have been constructed by pre-industrial humans alone.

  • They look at mythology of giants and Gods, massive structures like the pyramids that

  • show up across the world, and technology that seems too advanced for the time like the massive

  • clockwork Antikythera Mechanism of ancient Greece.

  • With sixteen seasons and almost two hundred episodes, there are a lot of believers.

  • But just as many detractors.

  • The Ancient Astronauts theory - and Ancient Aliens in particular - has been criticized

  • for using selective evidence and disregarding the contributions of early Native cultures.

  • The construction methods for megalithic structures like Stonehenge, the Great Pyramids of Egypt,

  • and the Mayan pyramids have been investigated and largely proven.

  • While there are still a lot of mysteries surrounding ancient architecture, like the giant stone

  • spheres of Costa Rica, few of them seem to point to aliens - but that hasn't stopped

  • the speculation from growing.

  • We don't know for sure if aliens have visited Earth - but there's a chance that their

  • DNA is still with us.

  • We might all be descended from aliens, if their organisms seeded our world eons ago.

  • The most likely scenario, if we evolved from alien microorganisms, is that we're so radically

  • different from the original species by now that there would be no similarity anymore.

  • If an alien species did seed Earth deliberately, then the odds are it didn't seed Earth with

  • the most advanced form of life on its planet but one of the smallest and easiest to transport.

  • The continuum of life on Earth indicates life likely started with microorganisms swimming

  • in the water before turning into larger forms of life and eventually heading onto land - a

  • far cry from the aliens who might have organized Earth's seeding.

  • But could humanity's ties to alien DNA be a lot more recent?

  • Many proponents of the Ancient Astronauts theory suggest that the aliens may have continued

  • to visit Earth up until the early days of humanity, and may have actually bred with

  • humans - leaving traces of their DNA in ours.

  • While the idea of aliens on a pleasure cruise looking for some exotic party times may be

  • relatable - especially if they have common DNA with those party kids who hit Cancun every

  • Spring Break - there are a lot of holes in the theory.

  • The aliens would have to still be around and in a similar shape billions of years after

  • Earth was first seeded, and they would have to be genetically compatible with humans despite

  • those billions of years of evolution.

  • So, no, it's not very likely that your great-great-great-great-great grandpa was an alien.

  • But that doesn't mean this kind of interbreeding between humans and their distant relatives

  • isn't possible.

  • Recent studies indicate that human fossils have traces of DNA from ancient humans that

  • preceded Homo Sapiens.

  • The more famous Neanderthals are in there, but so are an extinct species of archaic humans

  • we know relatively little about - the Denisovans.

  • Only identified in 2010 in Siberia, they've been identified from a few bones and teeth

  • that are distinct from other species.

  • When ancient genomes were sequenced for the first time, scientists found fragments of

  • genetic code that didn't match up with Homo Sapiens.

  • Neanderthals were quickly identified - in fact, it's estimated that most humans besides

  • Africans have up to four percent of trace Neanderthal DNA in their genome.

  • No one knows exactly what populations of ancient humans may be lurking in the recesses of the

  • human genome, both ancient and modern.

  • What we do know is that modern humans are a complex mix of influences that made us what

  • we are.

  • Could one of those influences be from beyond our solar system?

  • We don't have proof of that yet - but the human genome is a mystery, and we don't

  • have proof that it's impossible either.

  • For more on alien visitors, check outThis Will Happen When the Govt Confirms Aliens

  • Exist”, or watchHow Did the Dinosaurs Diefor more on the chaos objects from

  • space can cause.

Life on Earth.

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Why Some Scientists Are Saying We Are Actually Aliens

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    Summer posted on 2021/05/04
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