SELECT genus, species, continent ; 
    FROM Species P INNER JOIN Site S ON P.Pkey = S.fkey ;
    WHERE S.continent IN ('Africa','Asia') AND ;
        EXISTS (SELECT * FROM Site WHERE fKey = P.Key AND Continent = 'Asia') AND ;
        EXISTS (SELECT * FROM Site WHERE fKey = P.Key AND Continent = 'Africa') ;
    ORDER BY 1,2