mother animals are supposed to have a relative stronger mental ability thannon-mother animals. an experiment is conducted to test this theory, a group ofmother rats and a group of non-mother rats are involved in this experiment, theyare forced to find out the only right way to the fooD、it turns out that motherrats have a stronger memory, so they do not repeat turns and mistakes on the wayand they are faster than non-mother rats. In wild, it is similar that motheranimals also have stronger mental ability.