> but still the overall coordination seems so much more purposeful than something that would happen with a few initial mutations and then some further selection.
Isn't this just selection bias on a grand scale? You're looking at a specimen where the parts happened to end up arranged in a way that allows it to exhibit these properties that seem like coordination, while not paying much attention to the quintillions of specimens that did not.
>One theory of why you see so much symmetry in biology is that it takes less information to build something using symmetry than specifying the whole directly.
This makes a lot of sense.
It works the same way in computer programming. Instead of rewriting generic code for every new program, components can be split off into separate files and called when needed in a standardized way. This speeds up development and leaves less room for error.
It's not very far fetched to think other life forms are using the same strategy unconsciously to fuel their own evolution.
> But the combinations of amino acid sequences they would have to search through in order to find the correct shape is so large
Evolution isn't looking for that sequence.
It is looking for any change in sequence with a positive payoff, and in the meantime constantly diversifying sequences with similar outcomes, creating more opportunities for serendipity.
Every large animal is born with mutations. So we are also quite robust to spreading the search, running multiple experiments at a time, taking small risks with genes not quite as good, which will get weeded out quickly when combined with other weaker genes, but in the meantime cast a wider net for meshing with another gene that complements it.
So yes, in any given species with a nontrivial population, millions or billions of genetic variations are being explored at any point in time. We are nothing like carbon copies of each other, differing by just a couple checkmarks.
This is a radical speed up. Just as sexual recombinatory reproduction is. Evolution today operates with vastly more efficient genetic environment, structures and systems than what early life did.
Tractable statistics do no justice to how biology works and all the paths it searches. I am not knocking formal statistics at all, just noting that past one or two step events, the layered statistics of chemistry, genes, gene clusters, epigenetics, populatoin dynamics of complex creatures in their complex environments, etc. are not going to be tractably modelled.
Measurable sometimes for sure, but not symbolically characterizable or calculatable.
I'm not a biologist or geneticists but from everything that I've read about cellular biology and genetics I get the strong feeling that there is a lot of encapsulation going on. Sure, it isn't 100% percent perfect but there is still encapsulation going on. Evolution would probably be way harder without it.
One hint is the human body, there are lots of encapsulations: eyes, heart, kidneys, digestive system, etc.
Evolution can repurpose an existing system for a completely different use with just some tweaking.
> Pretty sure those non-cooperative strategies quickly burn themselves to extinction though.
> Pretty sure those non-cooperative strategies quickly burn themselves to extinction though.
Um, most life hanging out in the same tropic level or lower is heavily predated upon. Competition is the norm.
Luck is hard for cooperation because it is a coordination problem. You basically have to evolve cooperation entirely as a unexpressed trait then trigger it in the population almost simultaneously. The mechanisms of cell cooperation are critical dividers on our evolutionary trees for a reason, they are rare and dramatic in consequence. Cell populations regressing in terms of coordination behavior (see cancer) is one of their most problematic failure modes and it is only very weakly selected against.
> It is worth to mention that all living beings in earth are descendants of same cell. Even in earth there is no sign of multiple different cell formation which shows how lucky we were.
I don't see why this has to be the case. If unlikely conditions are correct for something unlikely to occur, then it's not longer unlikely to occur multiple times.
E.g. if you play around with chemical reactions and you hit the right conditions, it usually happens all over the place, and not just one molecule combining.
> Of course evolving the pupa seems like it would be a lot more difficult
Once you have evolved one intermediate form others can follow more easily. It’s always important to remember that genes define recipes that create biological structures, not blueprints of what they look like.
It’s a different mechanism but genetic networks are good at repeating things like body segments, fingers, etc. Biology invented the REPEAT UNTIL loop a long time before we did.
>But evolution is a random process based on the short-term advantages that emerge in each generation.
This idea is easily discredited, even "disadvantageous-but-viable" mutations are prized possessions among my offspring. Environments change, and whether or not my lineage goes unbroken is a result of its ability to survive those changes.
Those environmental changes are unpredictable. phenotypes that benefit me now do not necessarily benefit me in the future. If it is my goal to extend my lineage as long as possible, then my optimal strategy must give extra value to diversity.
Since every organism possesses a lineage that goes back to the origin of life, it's fair to say that cooperation for the goal of increasing diversity is a pretty heavily selected for trait.
Agreed, but the principle of convergent evolution is a thing. It's possible that and we cannot rule out that we are accidentally stumbling our way into homologous models of biological compute (I personally doubt it).
> what if the current genetic diversity on Earth is the result of genetic engineering by ancient aliums? [sic]
For purposes of explaining the last 4 million years of human evolution, it’s irrelevant whether conscious or unguided phenomena created forms even as recent as mammals.
> You're assuming a simplistic darwinist model that we already know isn't true
No, nobody is.
Retroviral horizontal transfer is fascinating, but it’s one of many mutation vectors. At the scale of speciation, the specific way a mutation arises can be largely ignored. (Creationism aside.)
> it seems at least mildly surprising that we've never observed at least similarly structured creatures.
Its not surprising that some survival-valuable features (especially when they fulfill a function for which there are other mechanisms) arise and are preserved and further developed only once, since them arising in a species in which they are survival-useful is a matter of chance, as is their preservation.
So, its not surprising that features we haven't seen in other species is continue to be discovered. Its remarkable enough to be newsworthy and interesting, but not something that fundamentally challenges the expectations and understandings we have from basic understanding of evolution.
> Random does not mean a uniform distribution. Toss 2 six sided dice and 2's and 12's are uncommon. But it's still a random process.
True, but dice don't adjust their own shape so that they're more likely to stop at certain values.
> Also, saying you often get some set of mutations may be likely if subsets of those mutations provide advantages or there is some process that makes those mutations more likely.
Yeah, but doesn't take away from the fact that evolution is canalised into certain options (most of the time) by its own evolutionary history.
> If there are "many jumping" insects, how does it come to be that only a single specie (that we know of, granted) that has evolved this feature, and why have we not observed others undergoing the evolutionary process that could/would yield them in others?
Because evolution isn't planned, it involves selection from randomly[1]-occuring variations each of which has a extremely low probability. Certainly, we see some some traits that arise independently in different populations in different places with similar traits and are preserved and develop in similar ways, but the fact that a feature that contributes to fitness arises uniquely in one place is far from surprising.
[1] well, really, many of the processes are highly-chaotic more than random, but that's beside the point here.
Isn't this just selection bias on a grand scale? You're looking at a specimen where the parts happened to end up arranged in a way that allows it to exhibit these properties that seem like coordination, while not paying much attention to the quintillions of specimens that did not.
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