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

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EARTH'S SHIFTING CRUST
ate, and the temperate species wcmld descend from their
mountains and migrate across the valleys southward to the
south temperate zone. In this way the migration of the species
from the northern to the southern temperate zone would
be accomplished.
Now this idea of the species clambering up and down the
mountainsides in response to the changing weather is a good
one, and gives us one key to the problem. Where Darwin
went wrong was in his alternating ice age theory; he could
hardly be blamed, in view of the prevailing ignorance about
ice ages. Darwin, of course, lived at a time when people were
first getting used to the idea of ice ages. But if Darwin was
wrong, if ice ages do not regularly alternate in the Northern
and Southern Hemispheres, how do we explain bipolar
have been
mirrorism? For some decades now, glaciologists
holding grimly to the theory that ice ages were always simultaneous
in the two hemispheres. In maintaining this view,
they have ignored the fact that they have made mincemeat
of Darwin's explanation of bipolar mirrorism. But this does
not concern them. They are concerned with explaining ice
ages, not with the distribution of species. They have sug-
gested no alternative explanation for the migration of species
across the climatjc zones. Instead, they have constructed a
theory that puts the migration of species, and even the survival
of tropical species, into the realm of sheer impossibility.
They insist, we remember, that the temperature of the
whole earth was simultaneously lowered in glacial periods.
We have seen that at various times in the past great conti-
nental icecaps have existed at sea level within the tropics,
and even on the equator itself. I have already pointed out
that if the world temperature had been lowered enough to
permit a continental icecap in the Congo, there would have
been no place of refuge for
tropical species of plants and
animals. Nowhere along the circle of the equator around the
earth would any tropical species have survived. This would
be equally true of land and sea forms of life.
Bipolar mirrorism, however, presents no problems
if we