[Hani1337]

I firmly believe that life on Earth was triggered by spores meeting water and developing mycelium networks breaking down minerals into nutrients and slowly taking advantage of photosynthesis to develop more complex life forms. Spores can easily resist the vacuum of space, and pass any form of great filter. They do help create enzymes and uptake nutrients, they do help break down minerals, they do communicate with entire ecosystems, and so much more we barely understand. This would mean that fungi are of alien origin.

[_Algernon_]

Are you suggesting that these eucaryote spores were the only source of life on earth? That would require them to have evolved into procaryotes which seems unlikely. It also doesn't really solve the question of how the alien life arose in the first place, so it lacks explanatory power.

[dieselgate]

This is actually a fairly reasonable theory given the information we currently have access to - not "spores" per se but rather by amino acids entering our atmosphere. Check out the "panspermia theory" as well as the "Murchison meteorite", I believe there may have been amino acids found on other meteorite samples since and perhaps one within the past 5 years or so. It's possible though our planet is very "ripe" for harboring life and there are multiple avenues through which it has evolved over time.

[yamasanama]

What advantage does this theory have over the more common (?) assumption that the amino acids came to existence on earth itself? Serious question, I'd like to know.

For example, this theory sti doesn't answer the question how they came into existence in the first place. It's certainly not obviously better than assuming they suddenly appeared on another planet and then transported to earth..

[nobody9999]

>For example, this theory sti doesn't answer the question how they came into existence in the first place. It's certainly not obviously better than assuming they suddenly appeared on another planet and then transported to earth..

Not sure what you're getting at WRT amino acids. Amino acids form due to the particular chemistry of carbon (what we call "organic chemistry"[1]), and they do so wherever both energy and the building blocks of amino acids exist. No planet required.

This was shown pretty well by the Miller-Urey experiments[2] as well as the discovery of amino acids in interstellar molecular clouds[0].

So...Amino acids can (and do) form wherever the raw materials and energy exist. That's the "how".

[0] https://physicsworld.com/a/amino-acid-detected-in-space/

[1] https://en.wikipedia.org/wiki/Organic_chemistry

[2] https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment

[mac01021]

So then they'd have formed on earth - no panspermia required?

[Hani1337]

planet is an amalgam of rocks and minerals, heat is provided by the sun, water could have been of extraterrestrial origin, and then enters fungi using heat and humidity to develop mycelium, mycelium turns minerals into compost with enzymes, space dust introduces bacteria which evolves through thermal vents a/biogenesis, and voila, you have life. We do know that before vegetation, Earth had fungi structures made of half rock, half fungi flesh, and they probably evolved into actual trees. At the same time, lichen spread from underwater to the surface of the Earth. Fungi released CO2, creating an atmosphere for plants to develop. The rest is evolution.

[dieselgate]

I'm not so sure it offers an "advantage" but it's rather just something we seem to have evidence for - indeed it does not answer any questions rather raising more possibly

[h_r]

One weak advantage is panspermia allows you to avoid the question.

[_Algernon_]

It doesn't though. It only requires for life to have evolved on another planet, reached space and then potentially traveled lightyears through space to reach earth.

Space is really fucking empty. Seems less likely than throwing a rock out of a rocket on the way to mars and hitting a random bucket, without looking. Add to that that it would require life having evolved while the universe was younger and different to the only state of the universe that we know to support life.

Is it impossible. No. But at that point the theory has as much explanatory power as creationism, i.e. none.

[dieselgate]

This made me laugh, yes I agree in a way. Maybe some day we will discover amino acid constituents on earth or another planet and it will fill in more of the blanks. It's the definition of chicken and egg though

[nobody9999]

Done. https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment

You may not have heard about it, as the paper describing the experiment was only published 69 years ago.

[dieselgate]

Thanks for the link and for the reminder, did learn about this experiment actually in organic chemistry years ago. Suppose it's a bit nonsensical to look for amino acid "constituents" then. Not a fan of the snark though

[polishdude20]

Check out some stuff written by Nick Lane. He's got a very well thought out theory of how life started.

[rhn_mk1]

The interesting implication of panspermia is that is yes, we would recognize alien life. I find this optimistic. Anthropocentric perhaps? Like a version of living in a slightly more sophisticated sci-fi show.

[asdff]

Thats assuming there is one single common origin for all panspermia. There could be multiple events and independent lineages. These are not mutually exclusive hypothesis because even with panspermia, life would have to originate somewhere to be seeded elsewhere.

[yamasanama]

Is your belief based on any kind of evidence in which case I'd love to hear your best arguments, or is it a religios belief (like in Jesus) in which case there is not much to discuss?

[darkerside]

Hypothesis is a key step in the scientific method

[yamasanama]

Sure. But stating a belief without any reason why this would be true, or more precisely, why this hypothesis would be preferable over the currently accepted hypothesis which does have supporting evidence, is just not very convincing.

[darkerside]

I'm just pointing out that you presented a false dichotomy. Just because it isn't proven science does not make it a religious belief.

[kevin_thibedeau]

Fungi are eukaryotes. They aren't a nascent life form.

[Hani1337]

Says who? They do present properties of thinkers when they regulated entire ecosystems via their networks of mycelium. They even communicated with micro electric impulses. Start thinking outside of the box, not within boundaries of definitions.