Gene Expression

Naturalistic biological evolution

The “standard model” of intellectual history presents the Presocratics as the pioneers of naturalistic explanations of the universe around us. This narrative explains how the messy natural philosophy of the Presocratics gave way to the more metaphysical and ethical schools of the late Classical and Hellenistic and Roman eras. In any case, Socialist Swine asks below:

I know that prior to Darwin people had some notion of evolution though they didn’t have a notion of the mechanism involved. Do you have any idea, who might have first suggested that species change over time?

Well, 10 minutes of google print pointed me to Empedocles, who did happen to be a Presocratic. His “theory of evolution” wasn’t exactly a process of evolution as we understand today. But, it is naturalistic, and it shows that evolutionary thought was not totally novel. The internet encyclopedia of philosophy has extensive commentary on Empedocles’ ideas, but if you want more, I suggest google print, or amazon’s search feature.

I have expressed the opinion that the human mind is biased against Darwinian evolution, but, the idea space that our species explores can be rather large. Even if you have an expectation, human variation (variance or error) often dictates that there are always those who swim against the current and generate some inevitable turbidity in the sea of human experience. In The Alternative Tradition: A Study of Unbelief in the Ancient World we see that movements like the Epicureans in ancient Greece, the Carvaka in India or the non-supernatural strain in Confucianism exemplified by sage Xunzi exhibit the naturalistic strain in intellectual history. This strain comes to the fore in complex literate civilizations where dissenters can attain critical mass and organize a counter-culture against normative supernaturalism (for instance, the Pyrrohnian Skeptics dominated the intellectual life of Athens until the rise of Neoplatonism during the Roman period). Of course we don’t need to look just to the naturalistic paradigm to see glimmers of a conception of evolution, the legends and mythologies of most peoples are riddled with transformation of animal to man and vice versa, so extracting the magical elements should naturally occur to some.

Addendum: From A Primer of Conservation Genetics:

The rate of mutation is critical to its role in evolution. Rates are low. For a range of loci in eukaryotic species, the typical spontaneous mutation rate is one new mutation per locus per 100,000 gametes (10-5) per generation (Table 3.1). Mutation rates are similar across all eukaryotes, apart from those for microsatellites.

…Mutation rates for quantitative characters are approximately 10-3 times the environmental variance per generation for a range of characters across a range of species. This apparently high rate, compared to single loci, is because a mutation at any of the many loci underlying the character can effect the trait.

What does this have to do with the rest of the post? I conceive of predisposition to religous belief as a quantitative trait. Some people are very “zealous,” some people not at all, and most people somewhere in the middle. The suggestion I’m offering here is that atheists and their ilk (our ilk) might, in part, be a byproduct of the genetic load of any population which is continuously replenished by loss of function mutation. In other words, the reason why we are always hanging around no matter the fact that our stereotypical asociality results in reduced fitness is that we are the end product of inevitable mutational processes. The low, but persistent, frequency of atheists and agnostics within a population might be a case of mutation-selection balance….


  1. #1 coturnix
    February 22, 2006

    Didn’t someone write a whole book about pre-Darwinian evolutionary ideas?

  2. #2 razib
    February 22, 2006

    yeah, several. hell, i know people personally who are working on pre-darwianian evolutionary theories (lamarckian in particular). but there is a perception i think that evolutionary ideas are a product of the rise of science in europe after 1600…when they aren’t.

  3. #3 David Boxenhorn
    February 23, 2006

    Does 10^-5 / 10^-3 imply that there are ~100 genes / quantitative trait?

  4. #4 razib
    February 23, 2006

    Does 10^-5 / 10^-3 imply that there are ~100 genes / quantitative trait?

    sounds right to me. though remember that empirically it can be hard to pinpoint with great precision beyond 5-6 genes…though QTLs are getting more powerful (FYI, until the recent work with ASPM, etc., the standard contribution of variance of IQ attributable to any locus from plomin et al. was about 1% per locus).

  5. #5 John Wilkins
    February 23, 2006

    The use of the term “evolution” tends to smear together some pretty disparate ideas. If by this you simply mean that species can change, then this indeed goes back to Empedocles or earlier, but if you mean a sequence of species change over time, Empedocles’ version isn’t it. He had the idea (according to Aristotle) that there were disconnected parts floating around that joined at random to form organisms, the most functionally coherent of which survived. In Henry Osborn’s 1894 book From the Greeks to Darwin Empedocles was proffered as a precursor, but in fact it is only a very vague resemblance, inspired by the desire to show Darwin was not original (which, in the case of natural selection, a good case can be made from the 19thC – I have found a 14thC writer, Frederick II who said almost the right thing, but nothing earlier).

    The idea that species transform into other species is both ancient – Aristotle said of animals in Africa that they mated at waterholes across “kinds” and this was the received view well into the 17thC. But more widely, the idea that all species are subject to change is first recorded in the 18thC, by Pierre Maupertuis, a century after the idea of species fixity was first explicitly stated by John Ray, and a decade after the Systema Naturae was first published by Linnaeus, making it an “official” view.

    Basically, species evolution had to wait for species fixism before evolution in any real sense could be proposed.

  6. #6 razib
    February 23, 2006

    i assume you speak ex cathedra john? :) thanks for the lesson, enlightening.

  7. #7 Matthew
    February 23, 2006

    What does this have to do with the rest of the post? I conceive of predisposition to religous belief as a quantitative trait. Some people are very “zealous,” some people not at all, and most people somewhere in the middle.

    You can’t see the similarity between the zeal of a Randi or Dawkins and the zeal of a Robertson? Both are missionaries for their respective belief systems. For that matter, look at political partisans. Zeal and the contents of the belief system that one is zealous about are two entirely seperate things.

  8. #8 John Emerson
    February 23, 2006

    The pre-Aristotelian naturalists were not very scientific. There were various arguments as to whether earth, air, fire, water, or all four were the most fundamental element. There was a move away from a personalized other-worldly god or gods, but often there were also beliefs that we would regard as providential, numerological or superstitious. In some ways alchemy was the culmination of this kind of thing, though alchemy had Muslim and Chinese antecedents too.

    The God of Marcus Aurelius, I recently found, is very depersonalized, but Marcus did believe in a naturalistic sort of providence within inevitability, much to my surprise.

    Contrary to common opinion, Aristotle was not just a rationalist but also did experimental work in biology. Some of his stuff is up on the net: History of Animals.

    What really seems to have stopped progress was the humanism, legalism, moralism, and political concerns of the Cynics, Stoics, Epicureans, and Skeptics — and later on, Christianity, of course. I personally would like to see these thinkers revived, but alongside science rather than instead of science.