Thursday, 7 February 2013

On the pace of cultural evolution

From a comment on a previous post:

Stephen Jay Gould (a more rounded intellectual than Dawkins on these issues) rightly called culture "the Lamarckian juggernaut" because of the pace of change and the ability to adjust, or in the terms of Lamarck "the inheritance of acquired characteristics."

I'm extremely sceptical about the idea that the pace of cultural evolution is fast because it is "Lamarckian". The most obvious hypothesis to account for the speed of cultural evolution being faster than evolution of human DNA is that ideas reproduce rapidly between brains, reproduce rapidly within brains, and are themselves the product of evolving signals in axons and dendrites, which reproduce at a lightning pace. So: incredibly short generation times accounts for most of cultural evolution's rapid pace.

As far as I can tell, most other attempts to account for the pace of cultural evolution don't fully account for the force of this point.

Anyway, I see no easy way forwards on this issue - short of a quantitative analysis. The rapid generation times and high parallelism of evolution inside brains can - in principle - be measured and compared with systems based on DNA - such as viruses and bacteria. I don't expect dramatic differences in evolutionary rates (however measured) per generation in systems with comparable parallelism. Intelligent design mostly speeds up evolution to the extent that it represents a high-speed parallel copying processes with short generation times. I think this is the most obvious null hypothesis for explaining the rate of cultural evolution. It's the baseline from which other hypotheses need to differentiate themselves.

6 comments:

  1. Technology begets technology, but more powerful than itself. We used hammers to make better hammers and now we use microchips to design better microchips. Or perhaps they use us? This may help with the puzzle of cultural acceleration, but is not necessarily Lamarkian.

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  2. Living things have always given rise to new living things - and over time the power of the biosphere to degrade sources of negentropy has increased.

    Evolutionary synergy is an ancient phenomenon too.

    Evolutionary progress is happening faster these days - but it is not a phenomenon which is unique to the cultural realm.

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  3. Adaptation is one thing, adaptability is another. Dennett's creatures illustrate new dimentions of agility (faster evolution), yet does not need Lamark. Reasonably, culture is an extension that confers yet greater agility.

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  4. Dennett's Scientific creatures - and Winfield's Walterian creatures - would surely be capable of the reverse engineering needed for the most sophisticated forms of Lamarckian inheritance.

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  5. "over time the power of the biosphere to degrade sources of negentropy has increased"

    I would be very interested to see a source on this. It certainly seems that the biosphere is a lot more interconnected than it used to be (flowering plants are only ~130My old, and most insects exploded when this happen).

    Also, are you sure you don't mean entropy? Biology is negentropic, so the idea that it is degrading the processes to create further negentropy seems opposite to what it should be.

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  6. What I wrote: "degrade sources of negentropy" makes sense. If you substitute in the term "entropy" instead the phrase becomes incoherent.

    Biology is not negentropic overall - any more than a fridge is negentropic. Both organisms and fridges decrease entropy locally but increase entropy globally. Look into maximum entropy production for more details.

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