Modern evolutionary biology replaced fixed racial hierarchy with dual evolution by nature and nurture.

Evidence

On June 6, 1947, these two commanding scholars published their groundbreaking article in the all-powerful Science journal. “Race differences,” Dobzhansky and Montagu wrote, “arise chiefly because of the differential action of natural selection on geographically separate populations.” They rejected eugenic ideas of fixed races, fixed racial traits, and a fixed racial hierarchy. Human populations (or races) were evolving, they argued, and changing genetically through two evolutionary processes: one biological, one cultural. It was not nature or nurture distinguishing humans, but nature and nurture. This formulation became known as the dual-evolution theory, or the modern evolutionary consensus. — Ibram X. Kendi, Stamped from the Beginning, 909

Categorization

• DEFINE: Defines dual-evolution theory / the modern evolutionary consensus — the nature AND nurture synthesis that displaced eugenics.
• XREF: Connects to the broader ignorance-to-hate-to-discrimination narrative arc Kendi is debunking — the ‘science’ that justified racism keeps mutating.