The Earth's Shifting Crust by Charles Hapgood - wire of information

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EARTH'S SHIFTING CRUST
similar to their accustomed climates. Some would disappear.
Some would develop varieties adapted to changed conditions.
Even though there would be no wholesale creation of new
plants and animals, the age-long process of change would
have received an acceleration.
Another important, generally accepted requirement for
evolution, as already suggested, besides climatic change, is geo-
graphical isolation to permit the development of new varieties.
Geneticists agree that the larger the population of a
given sort of plant or animal, the harder it is for a new variety
to get established, because crossbreeding tends to destroy the
new variety. If, however, populations are cut off from each
other, and are reduced in numbers, a new variant has a much
better chance to become dominant, and establish itself as a
variety in that locality. As already pointed out, crust displacements
can account for the alternation of conditions of
geographical isolation and intercommunication at the tempo
required to account for evolution, because they can account
for rapid, recurrent changes of sea level. Let us now visualize
the consequences of a displacement of the crust resulting in a
subsidence of a continental area displaced equatorwards. Let
us suppose a moderate subsidence of a few hundred feet only,
over a period of a few thousand years. The result, of course,
would be the deep intrusion of the sea into the continent.
The sea would invade valleys, cutting off one part of the
mainland from another, and creating islands and island
groups. Many populations of the same kind of plant or animal
would thus be isolated, and left for many thousands of
years to develop and establish new variant forms.
Let us suppose many new varieties to have become estab-
lished in the islands, and in areas of the mainland separated
from each other by tongues of the sea. The next requirement
of evolution is that these new varieties should be brought
into competition and that the best adapted of them should
be disseminated into more varied habitats. This might be
brought about by a new movement of the crust, such as
would displace this area poleward. The area will now be up-