Menarche. The average age of menarche, or first menstruation, in the United States is 12.88 years for Caucasian girls and 12.16 years for African American girls.A popular misconception is that menarche marks the beginning of puberty; in reality, menarche occurs later in puberty.enarche. The average age of menarche, or first menstruation, in the United States is 12.88 years for Caucasian girls and 12.16 years for African American girls.
Quick Answer. Roadrunners eat insects, lizards, scorpions, small birds, rodents and snakes, including rattlesnakes. During the winter months when its preferred food is scarce, the roadrunner may supplement its diet with fruits, seeds and other vegetable matter. Continue Reading.
The habitat of the Roadrunner is usually a nest placed a few feet above. ground in a bush, tree or cactus. Both the male and female will build. the nest and it may be built from sticks, leaves and other materials.