What is the Yerkes classification scheme?

The Yerkes classification scheme is a system used to categorize primates based on their social structures and behaviors. Developed by psychologist Robert Yerkes in the early 20th century, it classifies primate species into three main groups: the higher primates (such as apes and humans), the lower primates (like lemurs and tarsiers), and the prosimians. This classification helps researchers understand the evolutionary relationships and behavioral traits among different primate species. It underscores the diversity in social organization and cognitive abilities across primate taxa.