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As far as I know, there was no report of "life" popping up in a lab or in nature so far.

Everything that we know is only some copy with similarity to previous life-forms.

We certainly can mix some amino acids and stuff, and even some of the chemicals can retain some structure for a certain time and even form some proto-RNA-like structure (not sure how they called it in one document I have seen), but it's very very far from a living organism.

Does it mean that life cannot be "sparked" in today's Earth like conditions or, was it not even sparked here to begin with? I have read, as many others have done, this article: New research supports an idea that the Red Planet was a better place to kick-start biology billions of years ago than the early Earth was. They argue that you need molybdenum to create life-like structures and that it's not common in the right form on Earth.

What do you as biologists think about the statement that life cannot evolve on Earth because the conditions in the beginning of the Earth were not good for life to develop.

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    $\begingroup$ keep in mind todays earth is very different than the early earth, for instance life has drastically changed the atmosphere of the earth. $\endgroup$ – John Jul 19 '17 at 23:14
  • $\begingroup$ I have voted to have this question removed as off-topic. Please consult the help to see what questions are unsuitable. A suitable question asks for factual answer to a specific biological problem. "What do you think about the statement..." is not such a question. However interesting it may be it is an attempt to initiate a discussion to which any contributions (answers) are likely to be subjective. That is why it is off-topic. $\endgroup$ – David Jul 20 '17 at 9:16
  • $\begingroup$ There is a difderence between "conditions in the beginng of the Earth were not good for life to develop" and "Red Planet was a better place to kick-start biology billions of years ago than the early Earth was". If A is better than B, it doesn't mean (at all) that B is not good enough. Thats also the point people often forget while talking about evolution. $\endgroup$ – another 'Homo sapien' Jul 20 '17 at 11:48
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Three important concepts about abiogenesis

Let's start with three important concepts

Definition of life

You'll need to give a good definition of life, because biologists actually don't have one (it is a matter of philosophy to define life, not biology).

Time it took for life to emerge

Life as we know it emerged only after a huge period of time (hundreds of millions of years), which we obviously cannot reproduce in a lab.

Current competition

Even if some kind of protolife would appear at some point, it would still have to face the competition with its veteran partners. Hypothetical protocells would be eaten by some microbe with no doubt.

Panspermia

The idea of panspermia (the hypothesis that the life may have appeard in outer space or in another planets, and then "contaminate" the Earth) has been on the scene in many forms for quite a long time. Regularly we hear of some study which proposes that life, or at least some key biomolecule, may have formed in asteroids, comets, in Mars or somewhere else. They're quite interesting, mainly because they suggest more than one way that life may have appeared.

Molybdenum

While molybdenum is rare in the Earth, it still exists and so the study doesn't deny the posibility that life may have formed in the Earth. Nowadays, molybdenum is used by many organisms as part of the core of some key enzymes, such as nitrogenase (the enzyme complex that catalyzes the conversion of molecular nitrogen into nitrate). Molybdenum has very interesting catalytic qualities and may have been a key factor for the origin of life.

Phosphorus on Mars

However, those studies say that Mars has higher concentration of phosphorus, which is one of the main components of life, and that was pretty rare in the early Earth. The hypothesis is interesting but, without experimental data, it is only that. The authors suggest that nowadays those phenomena may happen in Mars, so the hypothesis may be confirmed in a few years as the exploration of the Red Planet continues.

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  • $\begingroup$ I modified the format of your answer (I mainly just added names to sections). Please feel free to roll back or re-edit if you don't like my edit. $\endgroup$ – Remi.b Jul 20 '17 at 0:23
  • $\begingroup$ Note that in addition to "hundreds of millions of years", there's also the fact that primordial life-creating "experiments" where likely taking place over a large part of Earth's surface, not just in a few test tubes in a lab. So there's extreme parallelism. $\endgroup$ – jamesqf Jul 20 '17 at 6:20
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This is really quite a question. And many leading biologists have tried (very hard) to answer it.

In my opinion, most of our incapacity to study which conditions can favor some form of "life" is due to a lack of understanding of what is "emergence". And moreover, about or focus on matter over processes, and the reductionist paradigm of modern science.

Life is an emergent, system-level, property of any living system. It is not the material basis of life what is important (for instance, just mixing all the biomolecule precursors in a soup has proven to be a poor attempt to recreate life-like behaviors). What is important is the way this matter is organized. But, again, what we don't understand is what "organization" even means. My intuition says that the answer will come from studying "organization" and not "matter". There is no reason to think that other life-like forms will have the same molecules (CHONPS, and water-based metabolic transformations), out of the astronomically huge universe of possible molecules that can exist by combining the finite number of stable atoms in the universe.

Then, let's understand organization. Let's understand emergence. Better, let's understand "radical emergence". Here I leave a link to some brief thoughts from one of the leading scientists of all of biology, Stu Kauffman.

Here is a more chemically-oriented opinion, by another leading scientist in the field (who recently passed away).

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