1990). These findings are less surprising when one considers that all
the outcomes in question are influenced by heritable traits such as
intelligence, impulsiveness, conscientiousness, and the like.
4.Heritability of personal environments.We tend to think of en-
vironments as “out there,” as external factors impinging on us, but
they too are shaped somewhat by our genetic proclivities. This is
especially so for our close interpersonal settings. For instance, both
our perceived and actual rearing environments are somewhat herita-
ble. Behavioral genetic analyses of scores on standard measures of
early rearing environments, such as the Home Observation for the
Measurement of Environment (HOME), routinely show that par-
ents’ behavior (warmth, toys provided, and so on) is shaped in part
by their children’s genetic differences. Scores on the HOME are
about 40 percent heritable. Behavioral genetic research “consistently
shows that family environment, peer groups, social support, and life
events often show as much genetic influence as do measures of per-
sonality” (Plomin, DeFries, McClearn, & Rutter, 1997, pp. 203–204).
The reason is that people with different genotypes are exposed—and
expose themselves—to different environments and experiences.
Environments can differ for (that is, correlate with) different geno-
types because parents transmit both their genes (say, aesthetic) and
their environments (art-laden) to offspring, which is called passive
gene-environment correlation.More important, however, is that differ-
ences in our personal environments are somewhat heritable because
we both evoke and seek out different experiences based on our ge-
netic proclivities: reactive(or evocative) and active gene-environment
correlation.For instance, teachers often inform bright students of spe-
cial scholarship opportunities, and bright students often actively seek
out tougher intellectual challenges. Proximal environments, then, are
not just externally imposed but are self-selected and self-generated.
5.Differential susceptibility to the same environments based on geno-
type. Some genotypes are more benefited (or harmed) by the same
environment or experience (medications, education, delinquent
peers, musical training, and the like) than are others. Take criminal
behavior, for example. Adopted children whose adoptive parents
112 CAREER CHOICE AND DEVELOPMENT