Israeli biologists Feder et al report on Selective breeding for dominant and submissive behavior in Sabra mice.
Mice are social animals and like many species, they show dominance hierarchies. When they first meet, they'll often fight each other. The winner gets to be Mr (or Mrs) Big, and they enjoy first pick of the food, mating opportunities, etc - for as long as they can remain dominant.
But what determines which mice become top dog... ? Feder et al show that it's partially under genetic control. They took a normal population of laboratory mice, paired them up, and made them battle for supremacy in a simple set-up in which only one mouse can get access to a central food supply:
At first, only about 30% of pairs developed clear dominance/submission relationships, but the ones that did were selectively bred: dominant males mated with dominant females, and submissive males with submissive ...
