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Comment by alex_young | Hacker News Reader

Given that our ancestors 65 MYA were very small rodent like creatures, I suspect any of “us” will be completely unrecognizable to the modern us.

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I believe we are at a juncture in human history where technological progress is so fast that it will eclipse any natural evolution that would normally occur. On a 250-million-year scale, we're nearing breakthroughs in halting aging, manipulating DNA on demand, printing body parts, and potentially even achieving mind uploading. Natural selection will soon have run its course for our species. We will keep evolving but it won't be driven by random DNA replication errors: it will be driven by technology and culture. I agree however that "they" will be completely unrecognizable to the modern us.

Written language popped up around 5 thousand years ago. https://www.getty.edu/news/where-did-writing-come-from/

Human language was invented ~100 KYA.

50 KYA we were painting pictures of mammoths on cave walls. Before that we were a population of ~200 for many tens of thousands of years in Africa.

Our earliest upright ancestors lived around 3 MYA. https://en.m.wikipedia.org/wiki/Lucy_(Australopithecus)

65 MYA the dinosaurs dominated our world and our ancestors were small rodent like animals.

It’s very hard to imagine that anything we do will stop evolution for hundreds of millions of years in the future.

If 65M years of random DNA mutations caused small rodents to evolve to homo sapiens, what do you think 65M years of human technology can do? Hint: technology progresses a lot faster than natural evolution. Think about how much of an impact evolution had on us in the last 1000 years vs how much technology did. We will probably become capable of editing DNA within a few generations. Death by aging will become a relic of the past. And I'm talking about what will happen within a few generations, not 250M years. In 250M years, DNA-based life will probably be mentioned in museums.

Tomorrow people will be better at remembering passwords and navigating virtual environments, by exactly the same process as any other organism adapting to it's environment.

My point was that the "same process as any other organism adapting to its environment" won't continue for very long for humans. Once you have people that don't die, DNA that can be edited at will, or even entirely non-biological bodies, you no longer have the ingredients required for natural selection.

Of course you do.

The most likely scenario for some time is at most a few thousand people that don't die a natural death, that can afford to edit DNA, and perhaps even transfer their mind into a tin can ... along side some greater than a few billion others who continue to practice natural selection.

How that works out in the long term will be .. interesting *.

* for some value of 'interesting'

Even non-biological bodies are subject to accidents, disasters, sheer neglect, or perhaps willful termination (for personal reasons, as punishment, kill for hire, ...). Everything dies at some point - no exceptions.

So essentially that would mess with the timescales. But you'd still have evolution somehow. Perhaps even fashion in what's considered desired physical format. Everybody bio/tech enhanced cyborg one year, everybody flying around as a drone the next year.

Indeed, by natural selection I meant evolution based on random DNA mutations. Of course, technological and cultural evolution (aka memetics) will persist.

Difference is rodent ancestor had to adapt to its environment. We haven't had to adapt to shit in millennia, that's the whole point of tech - to remove the discomfort of selective pressure.

We don't evolve anymore. Natural selection doesn't happen anymore.

Only way for that to happen would be interplanetary travel (particles and radiation in space affecting DNA for one, space colonies slowly changing over many generations to suit other planet's conditions more likely).

> We don't evolve anymore. Natural selection doesn't happen anymore.

I think we do. IVF, cloning and more. People choose to live in safe or risky places. etc...

Do you really believe that? Sexual selection is a thing of the past?

Natural selection sure, artificial though, definitely.

Women (on average) have preferences for taller guys (on average), where do you think the average height of people are headed? Artificial selection.

Most reproduction is monogamous in modern society. Artificial selection.

I don't mean to offend anyone with those examples by the way, apologies if I did. I also realize the irony that those examples might be opposing forces for the same phenotype I'm referencing.

Artificial selection refers to our selective breeding of non-humans. The examples you mentioned are natural selection.

People have a hard time understanding that humans are just animals and also part of nature.

Exactly. By the way, there's a name for human artificial selection: https://en.wikipedia.org/wiki/Eugenics

Sapiens has only been around for 300k years. Writing and, arguably, civilization is only 5.000 years old. If you subtract 5k from 300k, you still have about 300k left.

If you subtract 300k from 10 million years, you still have about 10 million years left.

The point here is that we are notoriously bad at gauging how big numbers are. We are also bad at intuitively gauging how fast/slow evolution moves.

We are very much still evolving and adapting to our surroundings. It's just that the big changes only become visible way beyond the horizon of a future we are able to conceive.

The only thing that makes human selection unnatural is that we like to define ourselves as above nature

In our resource-abundant modern world, you should expect genes that cause people to want kids to do very well. Fertility is low in most developed countries, but that masks particular sub-populations that are growing at a rapid rate. See this article for instance: https://medium.com/migration-issues/how-long-until-were-all-...

Similarly, expect future generations to be full of people who just can't stand wearing a condom during sex.

Anecdotally, it was my more risk taking and carefree friends that had kids first. I can see why - with just a little effort it's very easy not to have kids in the modern world, and the cost-benefit analysis for children is pretty bad.

What that means for the future of humanity, I don't know.

It's not necessarily that simple though. Maybe if you have an unplanned child early, you realize that thing about the cost-benefit analysis being bad, stop having kids, and reproduce at below replacement.

Here is one paper I found on correlates of reproductive success in the US, from 2005 though: https://d1wqtxts1xzle7.cloudfront.net/48563240/Sex_Status_an...

Just because we have defined ourselves outside of the term "natural" _doesn't_ mean we aren't evolving like any other species does.

> We don't evolve anymore. Natural selection doesn't happen anymore.

Of course we do. Why would we not? Evolution is just a fact of life. For it to stop happening, we’d need all humans to have strictly the same number of children who live long enough to have children themselves. As soon as you have something affecting fertility rates, you have selection pressure.

> particles and radiation in space affecting DNA for one

What makes you think this does not happen on Earth? Radiation is everywhere. So is chemistry: there are more ways to alter DNA. On top of that, DNA has intrinsic mechanisms for mutation, in the form of transcription errors. Mutations happen all the time.

Well, evolution doesn't happen nearly as much based on disease resistance, now that we have antibiotics. It doesn't happen nearly as much based on ability to survive famine, now that we have modern agriculture. It doesn't happen nearly so much based on ability to survive childbirth, now that we have hospitals. And so on.

That may have been their point.

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