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

LIFE 329
reconsider it in terms of displacements of the crust. One
movement, let us suppose, takes the Rocky Mountains 2,000
miles to the south. The species climb higher. Later, in a series
of movements of the crust (not always, of course, in the same
direction), the Rockies finally end up south of the equator,
in a temperate climate. Now the species climb down, and
occupy the temperate valleys of the Southern Hemisphere.
The mountain chain has functioned as
transporting species back and forth.
a ferryboat, simply
At this point it is interesting to reflect on how useful it is
to have these high mountain ranges. A low mountain range
would never do. It could never ferry a load of species across
the tropical zone.
5. The Periods of Revolutionary Change in Life Forms
The reader may have gained the impression that, while cer-
tain aspects of evolution have escaped satisfactory explana-
tion, at least the process itself has continued evenly through
all time. To this reader it may come as a shock, as it did to
me, to learn that this is not at all the case. There have been
remarkable variations in the rate of evolution. For long
periods it has marked time, and then some force, hitherto
unidentified, has initiated a phase of rapid change, a revolution
changing so many forms of plant and animal life as to
alter the general complexion of life on the earth. All paleontologists
appear to agree on this point. Dr. Simpson uses the
term "Virenzperiod" to define the periods of rapid change.
Others refer to "explosive" phases of evolution or to "quantum
evolution." It must be understood that development
during these periods is rapid only relatively; new forms are
still not created overnight.
One phenomenon that frequently occurs during these
periods is termed "adaptive radiation." This is a kind of ex-
rise to
plosion in which one form (or species) rapidly gives
dozens, scores, or even hundreds of new forms apparently at