The Wichita daily eagle. [volume] (Wichita, Kan.) 1890-1906, 1898-02-12
Points Of Modern Hygiene
NATURES CARE OF SEX RATIO

NATURES CARE OF SEX RATIO.
Professor ". K. Brooks of Johns Hop
kins. in the Baltimore Sun: Data which
have been gathered through long periods
of time in various countries show that
the ratio Of boys 10 girls in the birth
rate is lower in cities and large towns
than among the over worked, scantily-
fed and badly sheltered peasants of Eu-
rope; that is less among the well-to-do in
the cities than it is among the poor; that
it increases after long wars and in time
of agricultural depression and low wages,
and after long famine, and that, while
the normal birth rate is about los boys 10
100 girls, it may rise as much as one or
two per cent. under conditions of great
hardship.
Young husbands are seldom able to ef-
feet any great improvement in good liv-
ing, but all may experiment in hardships
and privations if they wish, and if the
head of a house chooses to conduct it as
if his house and country were in a state
of siege by a relentless enemy, he may do
so in the assurance well warranted by
science that if he have 1000 children he
may hope for about a dozen more sons
among them than his neighbor could ex-
pect.
The birth rate of each species. like its
natural term of life, is something which is
characteristic of the species, or natural,
and it has been fixed for the advantage OF
the species. All know that, while men die
at old ages and for many causes, there is
a natural term of life, and that, while
cat is old at 10 years, a crow, which does
not differ much in size or weight, or in
general activity form cat, may live for
centuries. So 1t is with the birth rate.
Each suecies has a characteristic birth
rate, and that birth-rate is that which on
the average is most advantageous to the
suecies. Animals which live long or are
little exposed to accident, and those abel
to protect and care for their young have
low birth-rate, while those which are
muhh exposed to danger, or short-lived
or unfit for giving their young parental
care and protection, have a high birth
rate.
The hen, which is short-lived and much
exposed to enemies. may lay 200 eggs
year, but the Mother Carey chickens,
which are said to be the most numerous
of all birds lay but one egg a year, but
these are laid on sand bars in the ocean,
where there is little danger to the eggs or
young.
So it is with the ratio between the sexes.
When a preponderance of one sex is
greatly advantageous to its species, that
sex predominates in the birth-rate. When
one sex is peculiarly exposed to danger
during infancy and younth, this danger is
met and provided for by nature through
an excess in the birth-rate of that sex.
young frogs there are about 14O
females and go males in each 200, but when
frogs are three and four years old the
sexes are equal. AS female frogs are ex-
posed to danger in the early part of their
lives, a nexcess of female frogs is produ-
ced. Among mankind infant morality is
much greater among boys than among
girls, and the birth-rate is adjusted to this
danger by an excess of boy birth.
1t is undoubtedly possible for man to
change by long generations Of selective
breeding the birth-rate of domesticated
animals or the ratio between the sexes,
but no one who is familiar with the sub
ject can hope for any sudden radical
change through the application of en-
pirical rules