life events, partially controllable ones (Plomin & Rende, 1991).Evidence from behavioral genetics suggests that the average heritability of the Big Five personality factors is about .41 to .42 somewhat less than the earlier twin study estimates of around .50 (Bouchard, 1994). It shows the heritability estimates for the Big Five from the Minnesota studies of twins reared apart.An interesting study that I can across was the study that Michael Lyons and his colleagues (1995) conducted. This study was regarding antisocial behavior among members of the Vietnam Era Twin Registry. The individuals in the study were about 8, 000 twins who served in the military from 1965 to 1975. The investigators found that among monozygotic twins there was a greater degree of resemblance for antisocial traits than among dizygotic twins. The difference was greater for adult antisocial behavior than for juvenile antisocial behavior. The researchers concluded that the family environment was a stronger influence than genetic factors on juvenile antisocial traits, and that antisocial behavior adulthood is more strongly influenced by genetic factors. In other words, after the individual grew up and left his family origin, early environmental influences mattered less and less. I found this research very fascinating due to the fact that I am an identical twin. I definitely agree that even if Anna (my twin) was separated from me, our genetic makeup is just too powerful that we would definitely be pretty much the same people we are today.Twins and GeneticsGenetics November 1st, 2000 ...
