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Comment by mnemonicsloth | Hacker News Reader

Yes, but there's a catch. The human race has existed for 140,000 years or so (edit), but has only been civilized for 7000.

The population of nomadic humans was lower, but there's evidence that they were much healthier than those who settled down to grow crops full-time. Agriculture was a win because it allowed for many more people to be born, but it's not a life for which we're well adapted.

ADDED: If this guy is right, 99% could turn out to be an underestimate or an overestimate:

http://www.ted.com/talks/aubrey_de_grey_says_we_can_avoid_ag...

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Some people argue that significant evolution has occurred within the human species after the civilisation started, most likely in response to the changing selective pressures brought on by civilisation itself. The book 'The 10,000 Year Explosion: How Civilization Accelerated Human Evolution' makes this case.

I'm not sure accelerated evolution is the right term, but the idea makes sense. Changing conditions exert selections pressures.

Dietary changes would have been a substantial. Lactose tolerance, for example is almost certainly new.

You can accelerate without changing speed - it's a vector.

evolution is not directional

I think that if the rate of genetic change increases then acceleration is an fair word.

If one defined the prevalence of each gene in the population you would get a vector were you could possibly 'change direction'. None of this requires any metric of 'goodness' to be defined if that is what you are worried about.

We've domesticated cows, pigs, sheep, goats, cats, horses, donkeys, chickens, and rabbits in, more or less, that time, creating substantial selective change. Even lab mice are pretty genetically different from wild mice, and that's within the last century or three, at most. So it wouldn't be that surprising if we had also domesticated ourselves.

Even our age as a species (it's a range depending on which estimate you take and how widely you define species) is very young. Even less if you consider our long generations (which we are). A thousand generations is nothing on an evolutionary scale.

What evidence is that? The average lifespan is on the increase, not the decrease.

Or are you using some other metric to measure what you call "healthier"?

If "healthier" is measured by number of mastodons killed with bare hands, yes, it's been a precipitous decline.

This article mentions it in passing:

http://news.ycombinator.com/item?id=533743

"We know roughly when and where farming began, because of the archæological evidence: domestication is a shock to the physiology of man and beast. The skeletons of people change, they temporarily grow smaller and less healthy, as the human body adapts to a protein-poorer diet and a more arduous lifestyle. Likewise, newly domesticated animals get scrawnier at first."

I'm sure some google wizardry could find a real source.

I'd say increases in the prevalence disease would have been the biggest factor in the reduction of lifespan for 'civilised' people.

There's always wikipedia:

http://en.wikipedia.org/wiki/Life_expectancy

The first subsection is "variation over time". The drop between the paleolithic and neolithic coincides with the development of agriculture.

This is a pretty contentious issue. The idea that humanity's single most (evolutionarily) successful technology caused a massive decline in individual quality of life is pretty disturbing, and some of the evidence is contradictory. It seems like a debate best left to experts, but I thought it was worth mentioning.

I still agree with the original post -- we're very lucky to be alive now.

Check out Jared Diamond's "The Worst Mistake in the History of the Human Race": http://www.awok.org/worst-mistake/

I was actually going to point to Jared Diamond as well! In his book The Third Chimpanzeem Jared writes about the immediate decline of health that followed the introduction of agriculture. By measuring the health of teeth, and etc we can see a noticeable drop in the years immediately following agriculture.

Looks like the article you linked to covers the same material.

Read "Guns, Germs and Steel" and "The Third Chimpanzee" by Jared Diamond. He talks a lot about the rise of agriculture.

When we look at how the average lifespan is increasing, we're only looking at the lifespan since the start of civilization as we know it - allowed by agriculture. It's possible that our quality of life is only now catching up to what our hunter-gathered ancestors had.

I can't up vote you enough for sharing the Aubrey de Gray talk. I can't believe I haven't seen that one!

Exciting isn't it. I quit smoking because of that talk, or rather, as part of a series of life changes inspired by that talk.

Fingers crossed!

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