[SauronOfMordor]

And if mating occurred with offspring, then they were not a separate species, but just another race of Man.

[Cronos]

well one step higher than “race” which is to some extent superficial — sub-species, so we are all Homo Sapiens Sapiens and neanders are Homo Sapiens neanderthalis

[blam]

"And if mating occurred with offspring, then they were not a separate species, but just another race of Man."

Extinct Humans

This book reveals at least seven extinct humans.
Since this book was written, another extinct human was discovered, Denisovans.
(Yup, you're part Densisovan too. The Tibetians inherited their 'high-altitude' gene from them.)

Why Am I Denisovan?

"When our ancestors first migrated out of Africa around 60,000 years ago, they were not alone. At least two of our hominid cousins had made the same journey—Neanderthals and Denisovans. "