how did that human (or homo erect-us or whatever) reproduce
Not necessarily. There are examples of breeding between animals with different numbers of chromosomes creating fertile offspring. And in the case of a fused chromosome versus some other complete mismatch like we'd find between different unrelated species, it is completely unclear that the result would be unable to reproduce.
Je Suis Charlie
Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)
If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass
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