Univariate genetic analyses for all of the variables included in the current study have been presented elsewhere (see Button et al. 2008; Rowe et al. 2008; Zavos et al. 2010). Briefly, each of the environmental variables is ~40 % heritable. The majority of remaining variance is attributable to environmental influences not shared by family members, with some evidence of shared environmental influences. Sex differences for all variables are minimal and/or largely non-significant.
