Explanation Of Gene Action As Related To Physiological

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that the pathogen, being a virus or bacterium withmany generations for
each generation of the host, could usually evolve faster than the host.
Thus the pathogen would usually not be very far behind the host in catching
up with that new resistance.
The pathogen would adapt itself to whatever
type of host was most common or abundant.
As soon as the pathogen succeeded
in adapting itself to the most abundant type, then selection turns against
that type and the uncommon types are favored.
Such a process would keep
the species forever on the run, keeping it from settling down.
The pathogen
may drive it from this combination to that and to that.
In the process of
being driven endlessly along this planless road, the species may stumble on
to some other importantadaptations.
He speculates that parasites and
diseases may have been a very potent factor in improving all species through
preventing them from resting on their laurels.
Hogsett:
We must adjourn this morning's session, because we must be
back here for a very important part of this program this afternoon at
one-thirty.
Thank you very much, Dr. Lush.