All other things being equal (natural resources and energy), technological progress is directly proportional to a population's size and density (for degree of p

All other things being equal (natural resources and energy), technological progress is directly proportional to a population's size and density (for degree of progress) and its growth delta (for the rate of progress). Interesting point. I had never heard it before (I'd be interested if you have a reference that goes into more detail), but it certainly seem like there is a historical correalation and thinking about it you do seem to need at least a minimum population size (enough to allow people to specialize in careers instead of everyone being generalists with food production their prime concern) to develop advanced technology. At least offhand, I am not certain how well that causitive factor holds after that threshold has been reached. And that All other things being equal caveat is likely to be of significant importance here. I am speculating, but I would guess that after the minimum threshold is passed than the amount of value the culture places on education and technology itself will likely swamp out size or growth rates in terms of encouraging technological advance. In other words, after the minimum is reached, you would increase technological development faster by affecting the culture of the people than by increasing the population, and that affect is likely to be so great to mask differences in population size. I haven't seen the movie yet, but I'm guessing the Na'vi did not have very large or dense populations. The total planetary population is never stated but the population for the region the movie focuses on is said to be in the neighborhood of 200,000 very roughly. As for their global Gaia network, does the movie explain if it actually transfer chunks of knowledge (memes) or experiential patterns, or is it 'lower level' and works more like sharing emotions? This is ambiguous. At one point it is shown that at least under certain conditions absolutely everything can be shared and transferred, but that was under exceptional circumstances. How it operates under normal conditions is left quite vague. The movie is well worth seeing if you haven't.