ISIR blog live # 4 update - Innovation, accidents and the evolution of intelligence

Here is installment #4 of my blogging "live" from the Internaltional Society for Intelligence Research (ISIR) 2005 conference in Albuquerque, NM.

Again....a paper with not much immediate practical value...except maybe for generating interesting cocktail trivia conversations. "In press" copy of the paper is available at Dr. Gottfredson's web page.

Gottfredson. Innovation, Fatal Accidents, and the Evolution of General Intelligence

Paper Abstract

• Since the 1970s, most evolutionary psychologists have conceptualized human intelligence as an aggregation of many independent, highly specific problem-solving modules, much like a Swiss army knife (Tooby & Cosmides, 1992). Some now cite the evidence for a g factor to argue that human intelligence is domain general. Their favored explanation for its evolution is that runaway selection for the ability to manipulate conspecifics was unleashed within groups when humans gained mastery over their external environment (“ecological dominance”; e.g., Geary, 2005). However, their explanadum is actually a postulated social or Machiavellian intelligence, which leaves g unexplained. I compile evidence from psychometrics, job analysis, personnel selection, accident analysis, and hunter-gatherer societies to show how external ecological forces could, in fact, have selected for g during the last half million years and also accelerated its selection after Homo sapiens emerged about 150,000 years ago.
• The following facts illustrate one such mechanism that could have selected for higher g: (1) fatal accidents (unintentional injuries) are a major cause of death in all societies, including the most technologically primitive (e.g., the Ache, !Kung), (2) fatal accidents disproportionately kill reproductive-age individuals, usually males while engaged in provisioning-related activities, (3) preventing accidents and limiting the injury they cause is highly g loaded, (4) hazards are ubiquituous in daily life, myriad in kind, and low-probability killers, so they tax attentional resources while tempting neglect, and (5) the fruits of provisioning competence are widely shared within human groups, but provisioning-related injuries are not. Daily life’s myriad hazards are like lightly g-loaded items on a very long mental test for avoiding accidental death: no single one matters much, but they cumulate over time and individuals to disproportionately cull the lower-g members of a group.
• Most hazards are evolutionarily novel because they are by-products of human innovations. While innovations lowered absolute rates of mortality, the new hazards increased g-related relative risk of death from unintentional injury. Rate of selection for g could have accelerated (i.e., g-related relative risk of death increased) when humans began flooding their EEA with innovations (fire for cooking and hunting, weapons, tools, rafts, etc.) whose hazards could exceed the limits of normal human tolerance (crushing, piercing, poisoning, drowning, brain trauma, etc.). I describe specific mechanisms that could have accelerated selection for g since the speciation of Homo sapiens: double jeopardy, the Spearman-Brown pump, spiraling complexity, contagion of error, and the migration ratchet. The general thesis is that the most powerful ecological forces selecting for g were not the joint threats to survival that riveted the attention of early human groups (starvation, warfare, etc.), but the relentless parade of less obvious, less compelling threats to the survival of individuals, one by one.

Presentor aruged that human "innovation" was the primary variable that influenced the probability of accidents and subsequent evolution of general intelligence. For example, more innovations-->more complexity-->more hazards-->bigger consequences (accidents and risk)-----results in more "pruning" of low end of g distribution. That is.....brighter people in populations increase innovation, that via the sequence above, results in greater risk of accidents and deaths for the entire population, which, because of their lower g, results in greater death among those low in intelligence....thus resulting in general increase in g over time.

Hmmmm. Brighter people make life more risky for the rest of the population?


Technorati tags: psychology. intelligence. intelligence theory. general intelligence. evolution. evolutionary psychology.