The Average Age of , a Girl's First Menstrual Cycle

question 13

Short Answer

The average age of , a girl's first menstrual cycle, dropped during the twentieth century.

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Definitions:

Human Evolution

The lengthy process of change by which people originated from apelike ancestors, spanning millions of years.

Biological Anthropology

The systematic study of humans as biological organisms. Also known as physical anthropology.

Primatology

The scientific study of primates, including humans, their evolution, behavior, and ecology, aiming to understand aspects of our own behavior and biology.

Ethnology

The comparative and analytical study of cultures; a branch of anthropology that examines the cultural variations among humans.