Last week I presented a summary of the method and findings of Ashraf and Galor’s American Economic Review paper The ‘Out of Africa’ Hypothesis, Human Genetic Diversity, and Comparative Economic Development (for the latest ungated version, go here). As discussed in that post, one limb of Ashraf and Galor’s argument is that genetic diversity provides a greater range of traits for the development and implementation of new technologies (which I’ll call innovation).

Four links this week: Paleofantasy: What Evolution Really Tells Us about Sex, Diet, and How We Live by Marlene Zuk. (HT: Evolvify) Ignorance, the Ultimate Asset has some good bits. Some interesting lines: Taleb, however, is so consumed with the downsides of a complex world and advises strategies so “hyperconservative,” that he often ends up preaching futility and paralysis. The Santa Fe Institute, likewise, has for years looked to complexity as the next economic paradigm but has mostly emphasized the chaotic nature of the economy and has thus run into explanatory dead ends.

Although the debate it triggered has been going for a few months (see here, here, here and here.), Quamrul Ashraf and Oded Galor’s paper The ‘Out of Africa’ Hypothesis, Human Genetic Diversity, and Comparative Economic Development has been published in the February edition of the American Economic Review (for the latest ungated version, go here - although you can download the data and supplementary materials from the AER site without a subscription).

Following my last post suggesting that there was no quality-quantity trade-off in modern societies (at least to an extent that mattered), I wanted to point to a nice model that makes this argument. The interesting thing about the model is that the purpose of the authors in developing it was not primarily to make that point. The model is by Oded Galor and Omer Moav model in their article Natural Selection and the Origin of Economic Growth.

Following his disappearance from Psychology Today, Satoshi Kanazawa has reappeared in big think (with not all happy with this move [Update: he’s now gone again, along with the post]). In a recent post, Kanazawa asks an interesting question - Why do people with many siblings have many children? Kanazawa writes: Studies show that fertility is substantially heritable; genes partly influence how many children one has. Children of parents who have many children also have many children; children of parents who have few children also have few children.

Four links this week: Quamrul Ashraf and Oded Galor’s paper on genetic diversity and economic growth has been formally published in February 2013 edition of the American Economic Review (ungated working paper version here). When its release was foreshadowed a few months ago, it generated some interesting debate (such as here and here, particularly in the comments). Starting next week I’m going to write series of posts examining the threads of Ashraf and Galor’s argument.

In my latest working paper, co-authored with Oliver Richards, we argue that recent fertility increases in developed countries may only be the beginning. From the abstract: We propose that the recent rise in the fertility rate in developed countries is the beginning of a broad-based increase in fertility towards above-replacement levels. Environmental shocks that reduced fertility over the past 200 years changed the composition of fertility-related traits in the population and temporarily raised fertility heritability.

Another interesting old paper off my reading pile has been Robert Sugden’s Spontaneous Order. Sugden asks us to picture a scenario where you are travelling down a road towards another car. You have two alternatives - move to the left or right. The other car has the same choice. If you pick the same, you pass safely. A game theoretic analysis tells us that there are three Nash equilibria – that is, three sets of strategies that neither driver would have incentive to deviate from (or put yet another way, each driver’s strategy is a best response to the other driver’s strategy).

This week we have paleo for dogs, irrational consumers and the question of what is the right size: John Hawks posts on a new Nature paper that provides a reason for “why we feed dogs kibble instead of raw beef” - well, at least those who don’t have their dogs on the paleo diet. Like humans with a long agricultural history, dogs have extensive duplication of the amylase gene, which assists in the digestion of starch.

Angus Maddison’s estimates of per capita GDP - from 1 AD through to the 2000s - are one of the most commonly used data sets in the examination of long-term economic growth. While Maddison passed away in 2010, a group of his colleagues created the Maddison Project, with the goal of continuing Maddison’s work. The project has just produced one of its first major outputs, an update of the original Maddison dataset, including estimates of economic development across the world from 1 AD to 2010.