# Brakefield et al., Nature 1996. Environmental diffs Genetic diffs.

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Brakefield et al., Nature 1996

Environmental diffs Genetic diffs

Prairie plant ecotype study (Cooper and Henderson 2002) Lespedeza capitata

Table 1: Mean Values for Measurements of Vegetative Traits: This table shows the mean values for the first and last days of measurement. Values in bold represent the highest mean for each column. Values on parentheses represent standard errors.

The evolutionary importance of heritability

Hirsch Maze

http://en.wikipedia.org/wiki/Great_Tit Parus major (great tit)

The (faulty) “reasoning” of The Bell Curve Differences in a phenotypic score among “populations”* * Note faulty assumption

The (faulty) “reasoning” of The Bell Curve Heritability of IQ score has been calculated in twin studies - if “genetic component” is removed from each “population,” the remaining variation (within “populations”) is due to environmental diffs.

The (faulty) “reasoning” of The Bell Curve Murray and Herrnstein conclude that differences between “populations” must be due to genetic differences since quality of environments can’t be this big. * * This is an example of “argument from incredulity,” rather than from evidence.

The “proper”* experiment * but not ethical or even worthwhile