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Primitive Asgard cells show life on the brink of complexity

quantamagazine.org

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Re: Primitive Asgard cells show life on the brink of complexity

#21

Post by causi »

baremetal wrote: post #18
meindnoch wrote: post #13

Earlier quoted context omitted.

It came from the energy that the Sun pumps into the system.

I understand we aren't a closed system. But that still doesn't explain to me where the complexity came from.

Ultimately this question is the question of why the universe isn't completely isotropic in all directions with a completely uniform distribution of matter and energy. To the best of our knowledge this is due to quantum effects at the beginning of time creating a temporary asymmetry whose resulting "sloshing" created everything more complicated than evenly-distributed hydrogen gas. Life on earth is the tiniest swirl of complexity in the vast waterfall of "wasted" entropy that is the sun burning out.

Re: Primitive Asgard cells show life on the brink of complexity

#22

Post by evv555 »

causi wrote: post #21
baremetal wrote: post #18

Earlier quoted context omitted.

I understand we aren't a closed system. But that still doesn't explain to me where the complexity came from.

Ultimately this question is the question of why the universe isn't completely isotropic in all directions with a completely uniform distribution of matter and energy. To the best of our knowledge this is due to quantum effects at the beginning of time creating a temporary asymmetry whose resulting "sloshing" created everything more complicated than evenly-distributed hydrogen gas. Life on earth is the tiniest swirl o…

>Ultimately this question is the question of why the universe isn't completely isotropic in all directions with a completely uniform distribution of matter and energy.

I don't think it's a self-evident given that going against the grain of increasing entropy leads to complexity. The obvious but naieve opposite of increasing entropy is going towards something like relatively simple crystal structures.

Re: Primitive Asgard cells show life on the brink of complexity

#23

Post by COGlory »

baremetal wrote: post #11
taxerbee1 wrote: post #2

A new study published in the journal Nature sheds light on the evolution of complex life from newly discovered "Asgard Cells"! Go science... love the science of evolution, so fascinating! So it seems like these Asgard Cells are complex cells that evolved on Earth over 1.8 billion years ago. These cells have features similar to both bacteria and eukaryotes, which are the two main types of cellular life on Earth. The d…

Where did the entropy in the genome of any species come from? The data man, where did it come from? When everything in the universe degrades or rusts or tends towards decreasing complexity. Edit: When I say entropy the first time I'm referring to algorithmic information theory entropy, whereas the second indirect reference is to physical entropy.

I would encourage you to find a copy of (it's very expensive, but there are methods to acquire it, such as "libraries") Eugene Koonin's "The Logic of Chance", if this is a topic you're interested in. It basically goes through evolution from a molecular biology and information theory standpoint (and culminates in his own theory of "genesis").

Re: Primitive Asgard cells show life on the brink of complexity

#24

Post by Symmetry »

haxxbro wrote: post #3

Implications for the search for extraterrestrial life! The unusually unique features of the cells suggest that it MAY have evolved elsewhere in the universe.

I think the speed at which the first life evolved on Earth but the painful slowness with which photosynthesis, eukaryotes, and complex life evolved on Earth make me optimistic about finding life forms but pessimistic about finding intelligent beings.

Re: Primitive Asgard cells show life on the brink of complexity

#25

Post by Symmetry »

taxerbee1 wrote: post #2

A new study published in the journal Nature sheds light on the evolution of complex life from newly discovered "Asgard Cells"! Go science... love the science of evolution, so fascinating! So it seems like these Asgard Cells are complex cells that evolved on Earth over 1.8 billion years ago. These cells have features similar to both bacteria and eukaryotes, which are the two main types of cellular life on Earth. The d…

Not quite, they have features of similar both typical archaea and eukaryotes, but living in close symbiosis with bacteria. We already pretty much knew that eukaryotes came from an archaea/bacteria merger, we're just much closer to figuring out how that happened.

Re: Primitive Asgard cells show life on the brink of complexity

#26

Post by Symmetry »

A pretty important piece of evidence on how the first eukaryotes came about. The two big schools of though were previously that symbiosis happened first before they merged or that the bacteria started out as a parasite living inside the archaea before developing symbiosis. The evidence for the later is that the bacterial ancestor of mitochondria seems to have been in the order Rickettsiales which contains the cell parasite that causes Typhus in humans. But seeing a species so similar to the arachea parent of the first eukaryotes in close symbiosis with bacteria seems stronger evidence the other way. It's not quite the classic hydrogen hypothesis[1] symbiosis but it's the similar.

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

Re: Primitive Asgard cells show life on the brink of complexity

#27

Post by FeepingCreature »

baremetal wrote: post #11
taxerbee1 wrote: post #2

A new study published in the journal Nature sheds light on the evolution of complex life from newly discovered "Asgard Cells"! Go science... love the science of evolution, so fascinating! So it seems like these Asgard Cells are complex cells that evolved on Earth over 1.8 billion years ago. These cells have features similar to both bacteria and eukaryotes, which are the two main types of cellular life on Earth. The d…

Where did the entropy in the genome of any species come from? The data man, where did it come from? When everything in the universe degrades or rusts or tends towards decreasing complexity. Edit: When I say entropy the first time I'm referring to algorithmic information theory entropy, whereas the second indirect reference is to physical entropy.

Randomization plus selection.

The big innovation of life is having a form of matter that can quine its own arrangement. Once you have that, the complexity that ensued was predictable.

Re: Primitive Asgard cells show life on the brink of complexity

#28

Post by throwaway173738 »

baremetal wrote: post #19
mcphage wrote: post #14

Earlier quoted context omitted.

I don't know why so many people forget that the laws of thermodynamics are all about closed systems, which the Earth is very much not .

I don't know why so many people forget to explain where _the complexity_ comes from and just drive right off the road assuming I don't know something basic and can distract from having to answer the real question about the complexity of the information in DNA and its origins. Not a very generous argument style you have there.

Have you never heard the joke about a million monkeys typing on a million towers eventually producing the complete works of Shakespeare? Little by little variation is accumulated when it’s beneficial, and the organism dies fast when it’s not.

Re: Primitive Asgard cells show life on the brink of complexity

#29

Post by meindnoch »

baremetal wrote: post #18
meindnoch wrote: post #13

Earlier quoted context omitted.

It came from the energy that the Sun pumps into the system.

I understand we aren't a closed system. But that still doesn't explain to me where the complexity came from.

The only question is where the first self-replicating structure came from. As soon as you have a self-replicating structure, you have evolution. Evolution is driven by these self-replicating structures competing for the available energy. A more efficient replicator outcompetes its less efficient siblings at exponential speed. If more complex replicators are more efficient, then complexity evolves naturally. It's basically stochastic gradient descent, with the environment as the training data, and replicator efficiency as the objective function. Evolution prunes all the inefficient branches, and what remains may seem hand-crafted, but in fact it's just what remains after everyone else got outcompeted.

Now, the question is whether the first replicator can arise randomly from the primordial soup or not? Was the first such replicator simple enough to be spontaneously assembled from random inorganic molecules floating in water? I think on a long-enough timescale, the answer is yes.

Re: Primitive Asgard cells show life on the brink of complexity

#30

Post by ch4s3 »

anonymouskimmer wrote: post #5
haxxbro wrote: post #3

Implications for the search for extraterrestrial life! The unusually unique features of the cells suggest that it MAY have evolved elsewhere in the universe.

We're all very much mixed at this point. But think of the other possibility: That the ancestor of the archaea lineage evolved on Earth while the ancestor of the bacterial lineage came from space.

> while the ancestor of the bacterial lineage came from space.

I don't believe this is supported by evidence. Finding a few organic molecules in a meteorite is pretty thin, and as Carl Sagan pointed out the lethal doses of radiation in space make panspermia highly unlikely.

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