Naked Science Forum
Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: InterstellarOctopus on 10/02/2020 01:48:04
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From what I’ve researched scientists have yet to create life like it happened first billions of years ago. If scientists can’t create life completely from scratch even with all our advanced technology and chemistry, how could life be created randomly from a chemical soup billions of years ago? I have struggle believing evolution for a number of reasons this being the main one.
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You are not describing evolution, you are describing Abiogenesis.
Evolution is the evolving of life not the beginning of life.
The beginning of life was not random, it was governed by the laws of chemistry.
Even if God or aliens started life on earth, that would not invalidate evolution theory.
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From what I’ve researched scientists have yet to create life like it happened first billions of years ago. If scientists can’t create life completely from scratch even with all our advanced technology and chemistry, how could life be created randomly from a chemical soup billions of years ago?
You seem to be assuming that scientists are already at a point where we can do anything that is physically possible. Obviously we aren't. We still have much to learn and technology still has a long way to develop.
I have struggle believing evolution for a number of reasons this being the main one.
As already stated, the theory of evolution is not about how life began. It is about how life developed after it got started. If abiogenesis was impossible, the theory of evolution would be unfazed.
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From what I’ve researched scientists have yet to create life like it happened first billions of years ago...
The building blocks of life can be created without design,
see ... https://wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
If scientists can’t create life completely from scratch even with all our advanced technology and chemistry...
See ... https://en.wikipedia.org/wiki/Synthetic_biology
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From what I’ve researched scientists have yet to create life like it happened first billions of years ago.
If scientists can’t create life completely from scratch even with all our advanced technology and chemistry...
This is confusing two very different things:
1. "create life like it happened first billions of years ago": ie without humans doing it
2. "with all our advanced technology and chemistry": ie with the most advanced human technology
The IF...THEN do not follow from each other.
Those among us who speak Latin would describe this as a "non sequitur".
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If you don't look exactly like both of your parents, you have evolved. No a theory but a definition. Look in a mirror and review your belief.
One reason nobody has synthesised a living thing in a laboratory is that there is no point in doing so. A second reason is that evolution seems to have added a lot of complexity, so we don't yet know what would constitute a minimal living creature, let alone what environmental conditions would be necessary for it to be demonstrably alive.
Meanwhile we have other impossibilities to contend with: heavier than air machines can't fly, steel ships can't float, humans cannot travel faster than a horse without going mad, and the world is flat.
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I have struggle believing evolution for a number of reasons this being the main one.
Good question, and isn't evolution just like the age of the universe....just a theory that has yet to be fully proven.
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I would also like to point out that scientists have not been able to achieve abiogenesis after... what? 100 years of trying? Let's say it's 1000 years, since "real" study of chemistry sing the scientific method started about then.
It seems that recognizable life on earth appeared within 1000000000 years of the earth forming.... so I wouldn't give up just yet...
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Good question, and isn't evolution just like the age of the universe....just a theory that has yet to be fully proven.
This raises an important point. Evolution is a fact (It does occur), how evolution works is the theory. The theory of evolution is very robust, but it is a theory that may be modified as more scientific discoveries are made.
It is along the lines of General Relativity, it is 'just a theory', but gravity is a fact.
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Why did life only generate once? We don't see new life crawling around the tidal pools.
Why does life have only one manner of replication? Is DNA the only answer?
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Why did life only generate once?
[ What evidence do you have for this assertion? Life as we know it probably evolved on Mars, the conditions elsewhere in the solar system seem favourable, and there are at least 40 000 000 000 000 000 000 000 potentially observable solar systems that we haven't begun to explore. Beware of the Kruger-Dunning syndrome.
We don't see new life crawling around the tidal pools.
Possibly the best place for it to evolve, but (a) there's lots of competition in a tide pool and (b) there's something like 8 000 miles of coastline to explore in the UK alone. The chances of anyone finding a new bug and proving that it had no organic ancestors are pretty small - we haven't catalogued all the "known" species yet.
Why does life have only one manner of replication? Is DNA the only answer?
I think the answer lies in the question. If you define life as being the effect of replicating DNA, there cannot be another.
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Life as we know it probably evolved on Mars, the conditions elsewhere in the solar system seem favourable, and there are at least 40 000 000 000 000 000 000 000 potentially observable solar systems that we haven't begun to explore.
I don't think we can say "life probably formed on mars." But I will grant that if we suggest that abiogenesis occurred on earth, then it is highly likely to have occurred elsewhere as well. And then we must ask, if abiogenesis can happen elsewhere, what are the chances that it happened there first (quite good) and what are the chances that our life came from there (easy from mars or any other inner solar-system object--and not impossible even for interstellar "spores" to find us.
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Why did life only generate once? We don't see new life crawling around the tidal pools.
Why does life have only one manner of replication? Is DNA the only answer?
As Alan said, how do we know it only happened once?
Also, I would dispute the idea of tide pools as likely candidates for abiogenesis locations. The life teeming around black smokers on the ocean floor indicates favorable conditions for life--and we are fairly sure that the environment around these vents is not very different now than it was billions of years ago (stable temp, pressure, alkalinity, salinity etc. etc.). Compare to tidal pools, which have experienced so many different climates (and occur in all sorts of rock), that it is unlikely that they would reproduce any of the chemistry that was applicable 3.5 billion years ago. Also, it appears that black smoker type vents are present and active on both Enceladus and Europa, increasing the number of potential places in the solar system that life could develop (or could have developed).
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We don't see new life crawling around the tidal pools.
It would probably get eaten before it had a chance to get established
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Why did life only generate once? We don't see new life crawling around the tidal pools.
Why does life have only one manner of replication? Is DNA the only answer?
Life could have sprung up multiple times. But over time, one version would have gotten a jump ahead of the others, out competing, reproducing more, and eliminating the competition. You don't get new life forms in tidal pools because, as mentioned, the conditions, aren't quite right. Besides, any new simple life that arose would quickly be preyed on by the more advanced life forms already there. They'd be wiped out before they ever got a foothold.
DNA may not be the only solution, but it is the one that came out on top on Earth.
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it is the one that came out on top on Earth.
... so far.
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I don't think we can say "life probably formed on mars."
The surface temperature range is not far from terrestrial arctic conditions, and below the surface the range will be much smaller. There is evidence of water and carbon dioxide. As far as we know, these were the only necessary precursors to life on earth. Mars has been around a long time. So to the best of our current knowledge, it is entirely probable that life appeared at some time on Mars, even if it didn't evolve to the density and complexity we take for granted.
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I don't think we can say "life probably formed on mars."
The surface temperature range is not far from terrestrial arctic conditions, and below the surface the range will be much smaller. There is evidence of water and carbon dioxide. As far as we know, these were the only necessary precursors to life on earth. Mars has been around a long time. So to the best of our current knowledge, it is entirely probable that life appeared at some time on Mars, even if it didn't evolve to the density and complexity we take for granted.
Perhaps this is just semantics (what is the definition of "probably"? more likely than not? can we assign a probability to something that actually did or did not happen? I guess we can define a certainty)
I am in agreement with most of the content of the post quoted, but am still uncomfortable with the statement: "life probably formed on mars"
There is overwhelming evidence that mars was once habitable by what we know as life (and may even still be below the surface).
There is some (controversial) evidence that there were microbes on mars. https://www.space.com/33690-allen-hills-mars-meteorite-alien-life-20-years.html (that rocks are exchanged between mars and earth is another fact in support of the notion of panspermia, but by no means is sufficient to base claims on)
As far as I know, there is no overwhelming evidence that there was life on mars at any point (other than what we may have sent by accident: https://www.nature.com/news/mars-contamination-fear-could-divert-curiosity-rover-1.20544)
In my own mind, I am fairly confident that there was life on mars, and likely still is on Europa and/or Enceladus. But as a scientist, I would be very cautious in making that claim.
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Given that people have looked rather carefully for evidence of life on Mars, but found none, I think it's inaccurate to say there was probably life there.
"Possibly", yes, but not "probably".
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We're arguing about the length of a piece of string that none of us has seen, but a few Mars landers have at best scratched the surface. I'm pretty sure that an alien probe to Earth in a couple of billion years' time will find it hard to see evidence of life ever existing in the top six inches of dust.