Premise: Mammals are any vertebrates within the class Mammalia ( [ məˈmeɪli.ə ] from Latin mamma #Latin `` breast '' ) , a clade of endothermic amniotes distinguished from reptiles ( including birds ) by the possession of a neocortex ( a region of the brain ) , hair , three middle ear bones and mammary glands .
Hypothesis: Mammals failed to develop a neocortex.
Label: CONTRADICTION