noun
also foe·tal·iza·tion ˌ ̷ ̷ ̷ ̷ə̇ˈzāshən, -ˌīˈz-
( -s )
: a retention in the postnatal life of higher forms of conditions occurring during development of related lower forms
the human skull shows fetalization in comparison to the gorilla's since it resembles the simple infant gorilla skull rather than the massive specialized adult skull