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Tibor Gánti's ideas about the origins of life

nationalgeographic.com

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Re: Tibor Gánti's ideas about the origins of life

#41

Post by davidhowlett »

Ericson2314 wrote: post #32
adrian_b wrote: post #27

Earlier quoted context omitted.

It is pretty certain that the first life did not use any kind of genetic material, because that is impossible. When RNA or any other kind of genetic material first appeared, the first thing that must have been possible to do with it was to copy it, a.k.a. to replicate it. If the genetic material was used first to do anything useful, e.g. to control protein synthesis or to catalyze directly any useful reaction, that g…

Have you seen the research of Ribosomes being quine-like? (the structural nucleic acids and genes for the protein parts are related).

I haven't seen that research but I find the idea fascinating. Where can I read more about this?

Re: Tibor Gánti's ideas about the origins of life

#42

Post by adrian_b »

Ericson2314 wrote: post #32
adrian_b wrote: post #27

Earlier quoted context omitted.

It is pretty certain that the first life did not use any kind of genetic material, because that is impossible. When RNA or any other kind of genetic material first appeared, the first thing that must have been possible to do with it was to copy it, a.k.a. to replicate it. If the genetic material was used first to do anything useful, e.g. to control protein synthesis or to catalyze directly any useful reaction, that g…

Have you seen the research of Ribosomes being quine-like? (the structural nucleic acids and genes for the protein parts are related).

While that is an interesting fact about the evolution of ribosomes, no kind of ribosome could have ever appeared, except after the process of RNA replication was already a perfected process.

Otherwise the first ribosome would have disappeared soon after it was first assembled, without leaving any descendants.

The first ribosome was probably made only of RNA, as there were no other ribosomes to assemble the ribosomal proteins, so it is not surprising that at some point some of the ribosomal RNA segments were replaced by proteins transcripted also from some ribosomal RNA segments, if that happened to improve the ribosome structure.

Re: Tibor Gánti's ideas about the origins of life

#43

Post by Razengan »

angst_ridden wrote: post #10
Ericson2314 wrote: post #5

Considering that the first proto-computers were not programmable, I can't help but be skeptical that the first life needed genetic material. Certainly there were lipid membranes. Maybe there were spontaneous proteins, maybe there was purely-catalytic RNA. I guess it's also a matter of line drawing. I'm OK with calling crystals life, for example. One should feel bad about breaking up big ones the same as one should fe…

I think you've got a minority opinion calling crystals "alive," although it does jibe with one definition of life that I heard: "any self-sustaining system that reduces internal entropy."

> "any self-sustaining system that reduces internal entropy."

Planet Earth would/should definitely count as alive, especially if it "reproduces" via us terraforming other planets to become like Earth.

Re: Tibor Gánti's ideas about the origins of life

#44

Post by api »

angst_ridden wrote: post #10
Ericson2314 wrote: post #5

Considering that the first proto-computers were not programmable, I can't help but be skeptical that the first life needed genetic material. Certainly there were lipid membranes. Maybe there were spontaneous proteins, maybe there was purely-catalytic RNA. I guess it's also a matter of line drawing. I'm OK with calling crystals life, for example. One should feel bad about breaking up big ones the same as one should fe…

I think you've got a minority opinion calling crystals "alive," although it does jibe with one definition of life that I heard: "any self-sustaining system that reduces internal entropy."

My favorite version of this classifies life as an exotic phase of matter in the sense of other exotic phases like Bose-Einstein condensates, etc.

Life is a phase of matter in which the dynamics of information and Turing-complete computation overcome the ordinary dynamics of matter and energy. I am not aware of who originated this idea, but I heard it from Christoph Adami (a researcher in evolutionary information theory). I also recall someone at a conference proposing the term "Turium," for "Turing-complete phase of matter."

Earth just happens to have an environment that contains a large abundance of this phase of matter, much like how stars are full of plasma etc.

Re: Tibor Gánti's ideas about the origins of life

#45

Post by dekhn »

sterlind wrote: post #34
dekhn wrote: post #31

Earlier quoted context omitted.

This is just wrong (as you say, careless). The criteria is "metabolism", not growth and reproduction. Similarly, viruses are not alive although they can reproduce. Interestingly, there are some highly parasitic organisms with limited ability to metabolize, that is, they have lost their genes and instead depend on their host organism (but I think all those examples still have some level of metabolic capability).

Viruses need a host environment to replicate. Fish need water and plant life or other fish to replicate. Algae needs nutrients to replicate. Every lifeform can only exist in some host environment. Viruses simply happen to have biological host environments, right?

this is certainly not the mainstream way of thinking; it's certainly not specific enough.

Re: Tibor Gánti's ideas about the origins of life

#46

Post by kadoban »

breck wrote: post #39

Has anyone seen a visual tree of life that starts before life on earth? Or in other words, say at some point we discover aliens in a distance galaxy. Would we be cousins? Are there visualizations that show what that kind of family tree would look like? I am a neophyte in this area but I'm sure there's a lot of good research out there.

Without seeing what's out there I don't think any such trees would make sense to draw. There's too many possible ones, and the branches would just be "?". We could be cousins of several sorts, convergently evolved to have some similarities, be completely unrelated in any way to other life, or any of several combinations of those.

And that's just the broad strokes, trees would be the details.

It's worth noting also that even only considering life on Earth that we already know about, the "tree of life" is already kind of a broken abstraction. Consider bacteria that are able to share genetic material without an ancestor relationship for instance, or closer to home even viruses that infect humans or any other kind of mammals. They affect our genetics in ways the tree doesn't/can't capture.

Re: Tibor Gánti's ideas about the origins of life

#47

Post by wanderingstan »

breck wrote: post #39

Has anyone seen a visual tree of life that starts before life on earth? Or in other words, say at some point we discover aliens in a distance galaxy. Would we be cousins? Are there visualizations that show what that kind of family tree would look like? I am a neophyte in this area but I'm sure there's a lot of good research out there.

“Panspermia” is the keyword to get you started.

https://en.wikipedia.org/wiki/Panspermia

Re: Tibor Gánti's ideas about the origins of life

#48

Post by ntsplnkv2 »

corobo wrote: post #2

Probably because news articles don't use his name in their headlines

Looks like the title was changed to add it.

I was also going to point out the irony that the news article cares more about the man rather than the discovery of the origins of life.

Re: Tibor Gánti's ideas about the origins of life

#50

Post by breck »

wanderingstan wrote: post #47
breck wrote: post #39

Has anyone seen a visual tree of life that starts before life on earth? Or in other words, say at some point we discover aliens in a distance galaxy. Would we be cousins? Are there visualizations that show what that kind of family tree would look like? I am a neophyte in this area but I'm sure there's a lot of good research out there.

“Panspermia” is the keyword to get you started. https://en.wikipedia.org/wiki/Panspermia

Bingo!
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