Subspecies

The hierarchy of taxonomic classification

Subspecies in biology (also known as bio-race, variety, breed) is a sub-division of a species that is identifiable by a cluster of traits that vary together geographically. For example, the key lime and the Mexican lime are two races, varieties, or subspecies of Citrus aurantifolia that differ consistently and geographically in several co-varying traits including peel thickness and color. No cluster of geographically co-varying genetic traits (bio-race) has ever been demonstrated in Homo sapiens.