Black leopards, also known as black panthers, are not a separate subspecies of leopard, but rather a color variation within the species. Black leopards have very dark brown background fur, against which their black spots do not show very well, although they are sill visible under bright light. Among the big cats, the leopard is most likely to produce melanistic individuals.
Black leopards appear among many of the leopard populations, especially in areas such as Southeast Asia, where low light conditions create a competitive advantage for their darker coloring. The gene for the dark coloring is recessive, so that two black leopards will have dark offspring, but two normally colored parents, who both carry the recessive gene, can often have black cubs appear among their spotted offspring.