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Question - Patterns in Evolved Animals


http://www.christinabarrett.com/2016/08/science-ancient-aliens.html

Science - "Ancient Aliens"

Humans as Aliens
On TV, there is a TV show called "Ancient Aliens." It seemed like they suggested we may have come from aliens.

Evolution
I believe more in evolution. Come to think of it, I do not understand why 1 species would always evolve together rather than having odd breeds staggering staying behind at a random variation.

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Life from Space
However, it seems true that life came to earth on comets or flying rocks/objects.

Old Living Organisms
I also saw on TV that there is a species somewhere else in the galaxy that has been alive as single creatures or a single creature for like over a million years. I think it is a small probably microorganism.
I have a question about the Evolution section I posted.

πŸ’™ Eurasian

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I do not understand why 1 species would always evolve together rather than having odd breeds staggering staying behind at a random variation.

Actually, if you look at primates in general, there's homo sapiens, gorillas, bonobo chimps, chimpanzees, and a wide variety of smaller primates (monkeys) as well as orangutans and baboons.
At one time homo sapiens co-existed with homo neanderthal.

Many other classes of animals have wide variation as well.

Impossible is illogical.
Lack of evidence is not proof.
 +  = 

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Life from Space
However, it seems true that life came to earth on comets or flying rocks/objects.
Not sure I understand your question, but I can say this: The Ancient Aliens show is notoriously pseudoscientific, so I wouldn't put too much stock into it. There is a scientific hypothesis called "panspermia" which holds that life was seeded onto earth from space, but it's extremely speculative and not very widely accepted among biologists as far as I'm aware (given that there are also several earth-based alternatives). In any case, it would just move the question of how life originated to a different setting, rather than actually answering it.

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The TV show seemed pretty sure of panspermia and it was in the past few years at least. Of course, life came on a comet as small organisms. I guess life is a thing that moves either inside itself or on the outside, and its food keeps it going. They believe in gods/God and aliens.

Eurasian

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What I'm saying is, the show does not reflect the majority opinion of scientists. It's trying to be sensationalist. Panspermia is not completely impossible, but there is no real evidence to support extraterrestrial origins for life on earth. And there are a few problems with it; for example, if life is continually rained down onto the earth from elsewhere, why does all life on earth seem to be closely related? Why would there only seem to have been a single seeding event? Second, while there are some extremophilic microorganisms that are highly resistant to cold and radiation, space is a really, really hostile place for life, and in the panspermia scenario life would likely have to survive for millions of years in such an environment before crashlanding on a new planet. It's questionable whether sensitive molecules like DNA can survive that long intact. And of course, there is no evidence that life even exists (or existed) elsewhere in the universe. And on top of that, it seems to be an unnecessary assumption, since the biomolecules found in nebulae in space can also be synthesized on earth (for example, near deep sea vents, or using clays as catalysts). And finally, like I said before, it doesn't really answer any questions, it just moves them to a different, unknown environment. So not impossible, but not very likely either.

There is a somewhat more plausible variant of this idea called "exogenesis", which holds that simple biomolecules could have been created early in the evolution of the solar system and then rain down on earth, thereby extending the conditions for the synthesis of such molecules a great deal, and making the rapid origins of life on earth somewhat easier to explain. Some people extend that idea to the synthesis of more complex structures such as early cell membranes, but again there are other ways of synthesizing these structures that don't require the additional assumption of extraterrestrial origins.

If you want to read more about the scientific ideas about the origins of life, I wrote a primer a few years ago: http://files.meetup.com/12930/Abiogenesis%20Explained.pdf
It's basically a summary of this video course by Robert Hazen, with a few small additions: http://www.thegreatcourses.com/courses/origins-of-life.html

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Wow, very impressive! 

Yes, it seems odd.

I saw on TV in the past like 1/2 year that there is life somewhere else that has been alive for like millions of years, like the living organism itself. It is a small form of life, like not a complex one, maybe like a microorganism. I guess it didn't have sex and split.

It seems all life on Earth is related, so maybe either there is a God or some parallel universe. Why would we be derived from more than one living thing? That living thing could have come on some meteor, tho I do not know how meteors work.

You know, it's amazing you stumbled across me because you did so much studying on this.

I looked at the pictures, too, and it seems like life is like a virus. If I studied something of a scientific nature for research, it might be that. They are a bit grotesque as they fester. If you understand science, it makes a lot of sense and doesn't seem too complex to grasp, I see.

Eurasian

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It seems all life on Earth is related, so maybe either there is a God or some parallel universe. Why would we be derived from more than one living thing?
Well, it seems we're not; A central part of evolution theory (with a substantial amount of evidence behind it) involves common descent, i.e.: that all life on earth has a single common ancestor (sometimes called the LUCA, for Last Universal Common Ancestor). Through evolution, life then diversified over billions of years into the different forms we know today. Evidence for the LUCA idea comes mainly from molecular biology; for example, all life shares the same genetic code (by which DNA is translated into proteins), the same basic metabolic processes (by which cells generate energy), the same types of cell membranes, the same molecular structure for its DNA and RNA, and so on. It seems it didn't have to turn out that way, and in fact scientists have (for example) synthesized DNA with different molecular "backbones" that seem to function just fine. The simplest, most likely explanation for the evidence we have is common descent.
That doesn't necessarily mean that life only originated once, though; maybe there were many independent origins, but the LUCA simply outcompeted (or ate) all the other ones, and they went extinct. It may even have been the case that life repeatedly originated and then went completely extinct again, only to originate again on the early earth. Or maybe it really did only happen once. Hard to say.
That living thing could have come on some meteor, tho I do not know how meteors work.
Meteoroids are basically rocks or dust grains floating around in space. When they get captured by the earth's gravity, they fall down into the atmosphere. At that point, they're called meteors. Because they're traveling really fast (typically more than 20 km/s), there is a lot of friction with the atmosphere, causing the outside of the meteor to glow and break apart. The dust trail it leaves behind is the "shooting star" that you see. Most meteors are really just small dust grains, and completely vaporize, but if one is large enough, a piece of it may impact the surface of the earth, and then its called a meteorite.
it seems like life is like a virus.
Well viruses are sort of in between living and nonliving. For example, viruses do not have their own metabolism, and they cannot reproduce by themselves. They're basically just a strand of DNA or RNA with a protein coating that protects them and helps them enter a host cell. The host cell actually does all the hard work for them. It's not entirely clear how viruses evolved, but some may have started out as so-called "plasmids", which are little bits of DNA or RNA that bacteria sometimes share with each other (they play a role in bacterial resistance to antibiotics, among other things).

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That's interesting, different forms of living. Viruses must be like demons. I read that fallen angels mated with people and there are half angels.
http://ichthys.com/mail-female-angels.htm

Likely to find other intelligent life, hopefully that is animal and not plant.

❇

Eurasian

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