South American drugs in Egyptian mummies is a fruitful field.

http://www.faculty.ucr.edu/~legneref/ethnic/mummy.htm

Also Charles Hapgood "Maps of the Ancient sea kings" raises a host of questions not adequately addressed by archeology.

among other things: Ancient Maps of pre ice Anarctica(only surveyed during the Int Geophysical year 1957?)
                     Portolans showing accurate maps of south america pre columbus.