1. Tupoc inca yupanqui was an contemporary of Columbus. So even if he did make a trip to Africa, his trip could not really be said to be a separate per-columban exchange.
2. Inca empire was on the pacific side of south America, it would be truly amazing if balsal craft with cotton sails as possessed by the incas could have traversed the Drake passage to reach Africa, much less return and round the Drake passage against wind and tide.
3. Yes, polynesians had Sweet potatoe. I forgot about that. But the absence of evidence of any other exchange, for example pigs and chickens that Polynesians took with them to virtually everywhere else they went, make the notion of substantial contact problematic. I might argue sweet potatoe might have been exchanged through some one off event, such as encounter of Polynesian and south American craft at sea, than through true land based contact involving fully stocked Polynesian ship with pigs and chickens landing in south america.
2. Inca empire was on the pacific side of south America, it would be truly amazing if balsal craft with cotton sails as possessed by the incas could have traversed the Drake passage to reach Africa, much less return and round the Drake passage against wind and tide.
3. Yes, polynesians had Sweet potatoe. I forgot about that. But the absence of evidence of any other exchange, for example pigs and chickens that Polynesians took with them to virtually everywhere else they went, make the notion of substantial contact problematic. I might argue sweet potatoe might have been exchanged through some one off event, such as encounter of Polynesian and south American craft at sea, than through true land based contact involving fully stocked Polynesian ship with pigs and chickens landing in south america.
