I have come across numerous studies done in Northern Ireland which show that this point is infact true. In these studies twins were seperated at birth, they were both placed into families with no criminal backround yet still showed extreme criminal behaviour. There are many more instances which also show just how apparent biological factors are. This is my opinion on the matter. I have a degree in biology, and a strong interest in this topic.
Most research seems to be in the area of testosterone and serotonin levels.
I am finally in graduate school and hope to learn alot more. I have come across numerous studies done in Northern Ireland which show that this point is infact true. In these studies twins were seperated at birth, they were both placed into families with no criminal backround yet still showed extreme criminal behaviour. There are many more instances which also show just how apparent biological factors are. This is my opinion on the matter.