1. Plural of polygenesis; the theory that different human races or species originated from multiple separate ancestral sources rather than a single common ancestor.
Usage: historical; anthropology; now largely discredited
2. In biology, the production or development of organisms from multiple independent origins or sources.
Usage: technical; biology

Examples

• Early anthropologists debated whether polygeneses or monogenesis better explained human diversity.
• The theory of polygeneses was used to justify racist hierarchies in the 19th century.
• Modern genetics has rejected polygeneses in favor of a single African origin for all humans.
• Some biologists studied polygeneses to understand how similar traits could evolve independently.
• The concept of polygeneses has been largely abandoned in contemporary evolutionary biology.