ls which struggle best with the forces that oppose their race.
But you could not show that the natural obstacles opposing human life
much differed between Sparta and Athens, or indeed between Rome and
Athens; and yet Spartans, Athenians, and Romans differ essentially. Old
writers fancied (and it was a very natural idea) that the direct effect
of climate, or rather of land, sea, and air, and the sum total of
physical conditions varied man from man, and changed race to race. But
experience refutes this. The English immigrant lives in the same
climate as the Australian or Tasmanian, but he has not become like
those races; nor will a thousand years, in most respects, make him like
them. The Papuan and the Malay, as Mr. Wallace finds, live now, and
have lived for ages, side by side in the same tropical regions, with
every sort of diversity. Even in animals his researches show, as by an
object-lesson, that the direct efficacy of physical conditions is
overrated. 'Borneo,' he says 'closely resembles New Guinea, not only in
its vast size and freedom from volcanoes, but in its variety of
geological structure, its uniformity of climate, and the general aspect
of the forest vegetation that clothes its surface. The Moluccas are the
counterpart of the Philippines in their volcanic structure, their
extreme fertility, their luxuriant forests, and their frequent
earthquakes; and Bali, with the east end of Java, has a climate almost
as arid as that of Timor. Yet between these corresponding groups of
islands, constructed, as it were, after the same pattern, subjected to
the same climate, and bathed by the same oceans, there exists the
greatest possible contrast, when we compare their animal productions.
Nowhere does the ancient doctrine--that differences or similarities in
the various forms of life that inhabit different countries are due to
corresponding physical differences or similarities in the countries
themselves--meet with so direct and palpable a contradiction. Borneo
and New Guinea, as alike physically as two distinct countries can be,
are zoologically as wide as the poles asunder; while Australia, with
its dry winds, its open plains, its stony deserts and its temperate
climate, yet produces birds and quadrupeds which are closely related to
those inhabiting the hot, damp, luxuriant forests which everywhere
clothe the plains and mountains of New Guinea.' That is, we have like
living things in the most dissimilar situations, and unl