Hominids
This first book of the Neanderthal Parallax spins two tales set in parallel worlds. In one, the neanderthal became the dominant species, evolving into a civilization similar in many ways to a human one, though sharply divergent in philosophy. In a lab accident, neanderthal physicist Peter Boddit crosses over to the parallel world, one inhabited by humans. He becomes a creature for study, and his lab partner must not only find a way to get him back but defend himself against allegations of murder.

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