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.

What was the primary goal of the first experiment conducted by Siberian scientists in 1959?

• To increase the size of silver foxes

• To domesticate silver foxes by breeding the tamest ones

• To make silver foxes more aggressive

• To change the color of silver foxes

What significant change was observed in the 8th generation of domesticated foxes?

• They developed new fur patterns

• They began to show affection towards humans

• They started to avoid humans

• They became more aggressive

What was the focus of the second experiment involving aggressive foxes?

• To make aggressive foxes more tame

• To change the diet of aggressive foxes

• To increase the lifespan of aggressive foxes

• To maintain the aggressive nature of the foxes

What did the transplantation of embryos from aggressive mothers into tame mothers demonstrate?

• Aggressiveness can be changed by the environment

• Aggressiveness is not influenced by genes

• Aggressiveness can be eliminated through diet

• Aggressiveness is preserved across generations

What conclusion can be drawn about the genetic basis of behavior from these experiments?

• Behavior is solely determined by the environment

• Behavior is not influenced by genetics

• Behavior is influenced by multiple genes

• Behavior is determined by a single gene