I know that the Neanderthal's are a branch of the Human Being but how do all three relate to each other or more specifically what is the difference?
Homo sapiens / Homo sapiens sapiens
Human being, in the popular culture generally refers to modern humans, called either Homo sapiens or Homo sapiens sapiens. The existence of the two names will make sense when talking about the Neanderthals. In the term Homo sapiens, Homo indicates the genus and sapiens indicates the species. In the term Homo sapiens sapiens, the second sapiens refers to the subspecies.
Homo neanderthalis / Homo sapiens neanderthalis
Neanderthals (or Neandertals) is sometimes referred to as a species in the same genus (Homo) than H. sapiens and sometimes as a subspecies of H. sapiens. When considered as a different species then, they are called Homo neanderthalensis. When Neanderthals are considered as the same species as H. sapiens but different subspecies, then they are called Homo sapiens neanderthalensis and modern humans are then called Homo sapiens sapiens.
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