Breeding and Behaviour

In 1959, Siberian scientists conducted two breeding experiments with silver foxes. The first aimed to domesticate foxes by selecting and breeding the tamest individuals, resulting in foxes that showed affection towards humans by the 8th generation. The second experiment focused on breeding aggressive foxes to maintain their aggressive traits, revealing that behavioral differences were genetic. Attempts to change these traits through embryo transplantation were unsuccessful, confirming the genetic basis of behavior. These studies demonstrated that selective breeding affects both physical and behavioral traits, with multiple genes involved in behavior.

How did the second experiment differ from the first in terms of the foxes used?

What conclusion can be drawn about the relationship between genes and behavior based on the experiments?