The expedition, led by organizer Norman Dyhrenfurth and climbing
leader Willi Unsoeld, was one of the most stunning accomplishments in the history of climbing, not just for the meeting near the summit of two successful teams from
opposite sides of the mountain, but for the teamwork that made the whole team much greater
than the sum of the participants.
In some species, both sexes possess ovaries and testes, and in one type of tropical fish, females can spontaneously switch their sex when the male
leader of an all - female harem is removed from the tank; males of the same species can do the
opposite if more
than one male
leader is around.