I am not surprised by this study, but it is still a good read on the day that’s in it.
The team gave questionnaires to 169 pairs of identical twins – 100% genetically identical – and 104 pairs of fraternal twins – 50% genetically identical – born in Minnesota.
The twins, all male and in their early 30s, were asked how often they currently went to religious services, prayed, and discussed religious teachings. This was compared with when they were growing up and living with their families. Then, each participant answered the same questions regarding their mother, father, and their twin.
The twins believed that when they were younger, all of their family members – including themselves – shared similar religious behaviour. But in adulthood, however, only the identical twins reported maintaining that similarity. In contrast, fraternal twins were about a third less similar than they were as children.
“That would suggest genetic factors are becoming more important and growing up together less important,” says team member Matt McGue, a psychologist at the University of Minnesota.