Views over Evolution
It is evident that the popular notion that scientific men have
declared that life cannot be evolved from non-life is very far
astray. This blunder is usually due to a misunderstanding of the
dogmatic statement which one often reads in scientific works that
"every living thing comes from a living thing." This principle
has no reference to remote ages, when the conditions may have
been different. It means that to-day, within our experience, the
living thing is always born of a living parent. However, even
this is questioned by some scientific men of eminence, and we
come to the third view.
Professor Nageli, a distinguished botanist, and Professor
Haeckel, maintain that our experience, as well as the range of
our microscopes, is too limited to justify the current axiom.
They believe that life may be evolving constantly from inorganic
matter. Professor J. A. Thomson also warns us that our experience
is very limited, and, for all we know, protoplasm may be forming
naturally in our own time. Mr. Butler Burke has, under the action
of radium, caused the birth of certain minute specks which
strangely imitate the behaviour of bacteria. Dr. Bastian has
maintained for years that he has produced living things from
non-living matter. In his latest experiments, described in the
book quoted, purely inorganic matter is used, and it is
previously subjected, in hermetically sealed tubes, to a heat
greater than what has been found necessary to kill any germs
whatever.
Evidently the problem of the origin of life is not hopeless, but
our knowledge of the nature of living matter is still so
imperfect that we may leave detailed speculation on its origin to
a future generation. Organic chemistry is making such strides
that the day may not be far distant when living matter will be
made by the chemist, and the secret of its origin revealed. For
the present we must be content to choose the more plausible of
the best-informed speculations on the subject.
But while the origin of life is obscure, the early stages of its
evolution come fairly within the range of our knowledge. To the
inexpert it must seem strange that, whereas we must rely on pure
speculation in attempting to trace the origin of life, we can
speak with more confidence of those early developments of plants
and animals which are equally buried in the mists of the Archaean
period. Have we not said that nothing remains of the procession
of organisms during half the earth's story but a shapeless seam
of carbon or limestone?
A simple illustration will serve to justify the procedure we are
about to adopt. Suppose that the whole of our literary and
pictorial references to earlier stages in the development of the
bicycle, the locomotive, or the loom, were destroyed. We should
still be able to retrace the phases of their evolution, because
we should discover specimens belonging to those early phases
lingering in our museums, in backward regions, and elsewhere.
They might yet be useful in certain environments into which the
higher machines have not penetrated. In the same way, if all the
remains of prehistoric man and early civilisation were lost, we
could still fairly retrace the steps of the human race, by
gathering the lower tribes and races, and arranging them in the
order of their advancement. They are so many surviving
illustrations of the stages through which mankind as a whole has
passed.
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