Talents that selectively facilitate the acquisition of high
levels of skill are said to be present in some children but not
others. The evidence for this includes biological correlates of
specific abilities, certain rare abilities in autistic savants, and
the seemingly spontaneous emergence of exceptional abilities
in young children, but there is also contrary evidence indicating
an absence of early precursors of high skill levels. An analysis of
positive and negative evidence and arguments suggests that
differences in early experiences, preferences, opportunities,
habits, training, and practice are the real determinants of
excellence.