Man In The Modern World

EUGENICS AND SOCIETY
energy. Agriculture demands foresight and the sacrificing of present
comfort to future benefit; in the more primitive modes of life, activity
springs more immediately from events. Agriculture demands steady
routine in one spot; the nomad and the hunter can profitably indulge
the spirit of restlessness.
Inevitably, it would seem, where early agricultural civilizations
were growing up, there must have been a considerable drift of
the more restless types out of them into the nomad and hunting
cultures on their borders; and quite possibly there occurred also a
converse movement inwards of more calculating and less restless
types.
Further, once the agricultural civilizations were well established,
a dominant class always appeared whose interests were bound up
with the success of the group. The members of this class therefore
were bound to encourage submissiveness and industry in the culti-
vators of the soil: and although much was in fact accomplished by
purely environmental means, such as religion and law, there must
again have been a selective effect, so that the level of inherent docility
would tend to rise in the peasant class. Thus in the long run, agri-
culture must have markedly increased the selective value of tendencies
making for the humdrum hard-working human virtues, and in its
secondary effects, as in the birth of the merchant class and in other
ways, have encouraged foresight and calculation.
Class differences in environment may also be selective. It seems
to be established that the inhabitants of our industrial towns are on
the average smaller and darker than those of the rural and small-
town population.1 It may well be that there is a selection against tall
and therefore rapidly-growing types on account of the unfavourable
diet and living conditions of the slum dweller, since slow growth
makes less demands upon a low supply of vitamins: and that tali
stature is on the whole correlated with fair complexion. But whatever
the cause, the fact remains, and can only be due to selection 9f some
sort.
A recent report of the Industrial Health Research Board a points
out that in the early part of the industrial era, the; demand in factories
was for men of good physique irrespective of build, while appearance
or presence counted for more in shops and offices. This may have
laid the basis for the observed fact that manual workers average
shorter than blackcoated workers, but are stronger. It is quite likely
that with the recent introduction of more automatic machinery,
1 Carr-Saunders, 1926, pp. 195-6.
2 Ind. Health Res. Bd. Kept,, 1935.
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