title: Twixt apes and angels: biology's search for the essence of humanness brings mixed blessings.
mesh_terms: D000827:Animal Welfare; D000818:Animals; D002678:Chimera; D005818:Genetic Engineering / Q000941:ethics*; D036281:Genetic Research / Q000941:ethics*; D006801:Humans; D002679:Pan troglodytes / Q000235:genetics; D012756:Sheep / Q000235:genetics; D013045:Species Specificity; D009927:Tissue and Organ Procurement / Q000379:methods