What if there were another advanced species?

Would we break bread with our brainy cohabitants or be locked in battle? What if Neanderthals, who bit the dust just 28,000 years ago, had instead wised up and were now living next door? Or what if, during all these millennia that humans have been evolving, some unrelated creature had evolved cognitive and technological prowess in keeping with our own? Another scenario: what if humans had split into two separate species - the original gangsters, and a successful evolutionary offshoot? These are all perfectly reasonable histories of the world that would have resulted in two advanced species of Earthlings living side-by-side today. They're just not the histories that happen to have happened. But what if they had? Would we break bread with our brainy cohabitants or be locked in a constant battle for supremacy?...read more>>>>...