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

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EARTH'S SHIFTING CRUST
one and the same time. How is this phenomenon accounted
for?
We must distinguish between the biological process and
the circumstances that cause it to occur. The is process easily
or animal is
explained. Let us suppose that a form of plant
widely spread over a considerable area. Its total population
may include some millions of individuals; over its whole
distribution there will be local variations in the environ-
ment, and consequently there will be selection pressures
operating simultaneously but in different directions on different
parts of the population in different habitats. New vari-
eties of the plant or animal will tend to appear to take
advantage of special opportunities offered by particular local
environments. This sort of thing is always going on, but it
does not, by itself, produce explosions of adaptive radiation,
Something more is required. Normally, a new variety of
any form has to compete with other forms already in possession
of the necessary supplies of food, light, and water. The
situation that has the particular combination of these things
required by a given plant or animal is referred to as its life,
or ecological, niche. Naturally, if this niche is already effec-
tively occupied the spread of the new variety is restricted,
As an analogy, think of a garden in which you have set out
one hundred expensive strawberry plants of a totally new
variety, just before being called away for two months on
urgent business requiring your presence in a foreign country
What now happens? Weeds immediately take over the niche
you had hoped to preserve (artificially) for the spread of the
strawberry plants. Their spread is restricted, and their survival
may be threatened.
In nature what seems to be required to permit the ver)
rapid dissemination of many new variant forms of the orig
inal plant or animal is an absence of competition. Empty life
niches are required. The question is, How is an empty life
niche produced? Occasionally, of course, it may have beer
there from the beginning; it may never have been occupied
form of life thai
because, presumably, there never was any