AN AMERICAN CENTURY OF BIOLOGY From both a geographic and
sociological perspective, the biology of the nineteenth century
was much like that of previous eras. The major ideas emanated
from Europe, stimulated by experiments carried out at the great
British and Continental universities. The three major biological
insights that dominated the thinking of biologists at the end of
the nineteenth century—the insights into evolution, heredity,
and development—all reflected Europe's continued preeminence in
biology. But the unifying principle underlying these three areas
of inquiry was not to be discovered by the biologists of the Old
World, but by the biologists of the new. Morgan's discovery that
the gene was the unit of Mendel's inheritance, that it was the
fuel for Darwin's evolution, and that it served as the control
switch for development inaugurated an American Century in
biology that accompanied the emergence of the American research
university and with it the assumption of American leadership in
all areas of