On the point of Egyptian maritime capability, I would note that they did not have to have direct contact with S America to receive their goods. The Phoenecians for one could have traded and passed on articles from both sides of the Atlantic whilst keeping the routes secret.
Absolutely correct that the AE would not have to go to South America :) But what goods would these be? Tobacco and Cocaine have been mentioned on this thread but lets consider these facts.
Regarding tobacco: There are plants besides American tobacco that would produce the readings found, this was pointed out by the researcher herself in 1993 but that information seems to be ignored (not saying by you btw) in the hoopla... other plants in the Solanaceae family (nightshade - belladonna) would produce the same readings. These plants are native to Africa, and then of course there is Nicotiana africana, which as the name implies is a tobacco native to Africa. I would also say again that AE mummies have in the past been doused with a tobacco spray to control infestations of bugs.
Regarding cocaine: Again, there are plants besides the American Erythroxylon coca that would produce a "cocaine" result.
Members of the Erythroxylon family that are native to Africa (or near) are:
E. brownianum_, Southern Africa
E. caffrum_, Southern Africa
E. delagoense_, Mozambique through South Africa
E. emarginatum_, Guinea to Kenya, Central and Southern Africa
E. gerrardi_, Madagascar and Mozambique
E. monogynum_, India
E. pictum_, Southern Africa
E. platycladum_, Kenya to Mozambique and Madagascar
E. pulchellum_, Southern Africa
E. zambesiacum_, Central Africa
Any of these African members of the Erythroxylon family could produce these readings as they all contain varying amounts of the alkaloid “cocaine.”
(Exell, A.M., Fernandes, A. & Wild, H. (1963), "Flora Zambesiaca", Vol. 2, Pt.1; and Harvey W.H. & Sonder, O.W. (1894-1933), "Flora Capensis", Vol. 1.)
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