Authentic Science Fiction Monthly No. 48 — page 117: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

AUTHENTIC SCIENCE FICTION precisely, it means that nature selects for survival those or- ganisms which are most fitted to live. Taking the reins out of nature’s hands and describing the process more exactly, we can say that organisms with disadvantageous mutational trends are less able than their non-mutant fellows to ~-com- pete in the struggle for personal survival (search for food, etc.) and for racial endurance (search for a mate); they, therefore, tend to die out before producing offspring. Conversely, those organisms with advantageous mutations tend to “‘crowd out”’ their less fortunate fellows. Mutations are only one way, so some experts believe, by which natural selection is instigated. Another is change in chromosomes. by “acci- dents” during cell division. During division of the repro- ductive cells the chromo- somes undergo a great many changes, being rearranged in the cell, split longitudinally and generally knocked about. As this process goes on bits of chromosomes are sometimes broken off and become joined to another, with consequent effect on the organism which develops from that cell. Thus, though the effect is the same (evolution) and the raw mater- ial is the same (chromosomes), the initial cause is probably not the same. This question of causation of chromosomal changes is one which is engaging the attention of a great many biologists at the present time, for it strikes at the very roots of scientific belief. Quite a few well-known and highly experienced géneticists believe that there is no cause in the usual sense of the word. They believe that mutations and chromosome “injury” hap- pen by chance. The idea of chance is something that scientists like to deal with only when it is expressed in strictly mathematical form— it then is more a measure of probability than of random- ness. But this concept of 116 comiclboooks.com