Why your pet rabbit is more docile than its wild relative?
Why does a wild rabbit flee when a person approaches it, but a domestic rabbit sticks around for a treat? A new study finds that domestication may have triggered changes in the brains of these-and perhaps other-animals that have helped them adapt to their new, human-dominated environment.
The leader of the research team, animal geneticist Leif Andersson of Uppsala University in Sweden and Texas A&M University in College Station, thinks the process of domestication has led to changes in brain structure that allow the rabbit to be less nervous around humans. To find out, he and colleagues took MRI scans of the brains of eight wild and eight domestic rabbits and compared the results.
The team found that the amygdala, a region of the brain that processes fear and anxiety, is 10% smaller in domesticated rabbits than in wild rabbits. Meanwhile, the medial prefrontal cortex, which controls responses to aggressive behavior and fear, is 11% larger in domesticated rabbits. The researchers also found that the brains of domesticated rabbits are less able to process information related to fight-or-flight responses because they have less white matter than their feral cousins do. White matter handles information processing. When a wild rabbit is in danger, more white matter is needed for faster reflexes and for learning what to be afraid of.