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Comment by tachyonbeam | Hacker News Reader

> It's like taking a random byte sequence from some binary, shoving it randomly into another, and the new binary gets useful new features.

If you think about it for a moment, our genetic code is kind of designed to work that way.

You get half of your genetic code from your mom, the other half from your dad, and somehow, all of these genes "just work" together. It's kind of miraculous when you think that there are very many genes that encode how your brain works, and how your liver works, your muscles, etc. Somehow, provided the baby can be born, a mishmash of genes from two different individuals almost always works out.

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Probably because they do not really encode how anything works and because, probably by necessity, the growth of organisms is a swarm intelligence that is quite self-healing.

In particular with coinjoined twins, it's quite remarkable how much the systems for body development still produce something that connects the inner workings, which was obviously not it's “purpose”,but the self-healing growth mechanisms that corrects for errors simply leads to that.

Consider the Hensel Twins who have two mouths but their digestive system at some point merges in a way that is capable of digesting. The “tubes” of their digestive tract actually merge at one point, but they have two stomachs.

"a mishmash of genes from two different individuals almost always works out" => different individuals of the _same_ species (which btw is how a "species" is defined).

The evolution of organisms that gene mishmash (aka sexual reproduction) is thought to be the result of an ongoing arms race between gene sequences that "try" to stay unchanged (in higher level species) and gene sequences that "try" to "free ride" (from viruses etc.) Being able to build members of your species from "mishmash of genes from two different individuals" has the effect of scrambling the DNA of each species member which makes attack harder.

Organisms that do not do this and reproduce via cloning (aka Parthenogenesis) are often entirely wiped out once a pathogen figures out how to target their DNA -- hence the bananas types we eat change over time.

ps: Similar evasion is used by some computer viruses: https://www.trendmicro.com/vinfo/us/security/definition/Poly...

> The evolution of organisms that gene mishmash (aka sexual reproduction) is thought to be the result of an ongoing arms race between gene sequences that "try" to stay unchanged (in higher level species) and gene sequences that "try" to "free ride" (from viruses etc.)

Sexual reproduction means your species has a very large gene pool, and individuals with new combinations of genes can be produced very quickly. That's not just an advantage against viruses. It's also very useful for adapting rapidly and competing against other species when your environment changes. New threats (and new opportunities) show up all the time, be it dwindling or changing availability of food, climate change (e.g. new ice age), new predators or new preys, and also a group of individuals migrating to a new region of the world with a different climate.

> all of these genes "just work" together

That's a little bit tautological since if the genes didn't work together they wouldn't be here after all these years, right? Fascinating nonetheless.

That seems to be the point the parent is making. Tautology is the the only way we can explain the way life happens to be -- it's because it's advantageous for it to be that way.

It should also be pointe out that about two thirds of human conceptions result into early embryonic death, so evidently it is not as smooth a ride as suggested.

I'm just picking nits, but :%s/designed/evolved/g

Do very much agree it's miraculous. Biological organisms are robust to error and chance in ways no designed system comes close to matching. It's awe-inspiring

In genetics it’s very common to say that things are designed a certain way without invoking a creator.

Yep, the designer is evolutionary pressures, not necessarily an inteligence. It's shorthand, not religious invokation.

I didn't know this was common usage, thanks! I stand corrected

No worries, you're more right now than you were before. :)

Maybe genes are declarative, not procedural har har har

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