A subspecies is a distinct group within a species that has developed recognizable differences from other groups of the same species, usually because they've lived in different environments for a long time. Think of it as a variation on a theme: all members of a species can still interbreed with each other, but those in different subspecies have adapted to their particular homes and developed their own characteristics.

For example, tigers are one species, but there are several subspecies including Bengal tigers and Siberian tigers. Bengal tigers live in warm forests and tend to be smaller with darker stripes, while Siberian tigers survive harsh winters and are larger with lighter fur. They're still tigers and could have cubs together, but they've each adapted to their environments over long periods of time.

Scientists identify a subspecies by looking at consistent physical differences, genetic variations, and geographic separation. African elephants have two main kinds that are sometimes described as subspecies: the forest elephant and the savanna elephant, each with distinct features suited to where they live.

In biology, when you see a three-part scientific name like Panthera leo melanochaita (the Southern African lion), that third word identifies the subspecies. The regular species name has just two parts, like Panthera leo for lions in general.