Message #128643

[Bullseye]

* The foregoing statements are taken chiefly from the following
works: Jarves' History of the Hawaiian Islands, 1843, pp. 400-407.
Cheever, Life in the Sandwich Islands, 1851, p. 277. Ruschenberger
is quoted by Bonwick, Last of the Tasmanians, 1870, p. 378. Bishop
is quoted by Sir E. Belcher, Voyage Round the World, 1843, vol. i., p.
272. I owe the census of the several years to the kindness of Mr.
Coan, at the request of Dr. Youmans of New York; and in most cases I
have compared the Youmans figures with those given in several of the
above-named works. I have omitted the census for 1850, as I have
seen two widely different numbers given.

  Lastly, Mr. Macnamara states* that the low and degraded
inhabitants of the Andaman Islands, on the eastern side of the Gulf of
Bengal, are "eminently susceptible to any change of climate: in
fact, take them away from their island homes, and they are almost
certain to die, and that independently of diet or extraneous
influences." He further states that the inhabitants of the Valley of
Nepal, which is extremely hot in summer, and also the various
hill-tribes of India, suffer from dysentery and fever when on the
plains; and they die if they attempt to pass the whole year there.

  * The Indian Medical Gazette, Nov. 1, 1871, p. 240.

  We thus see that many of the wilder races of man are apt to suffer
much in health when subjected to changed conditions or habits of life,
and not exclusively from being transported to a new climate. Mere
alterations in habits, which do not appear injurious in themselves,
seem to have this same effect; and in several cases the children are
particularly liable to suffer. It has often been said, as Mr.
Macnamara remarks, that man can resist with impunity the greatest
diversities of climate and other changes; but this is true only of the
civilised races. Man in his wild condition seems to be in this respect
almost as susceptible as his nearest allies, the anthropoid apes,
which have never yet survived long, when removed from their native
country.
  Lessened fertility from changed conditions, as in the case of the
Tasmanians, Maories, Sandwich Islanders, and apparently the
Australians, is still more interesting than their liability to
ill-health and death; for even a slight degree of infertility,
combined with those other causes which tend to check the increase of
every population, would sooner or later lead to extinction. The
diminution of fertility may be explained in some cases by the
profligacy of the women (as until lately with the Tahitians), but
Mr. Fenton has shewn that this explanation by no means suffices with
the New Zealanders, nor does it with the Tasmanians.
  In the paper above quoted, Mr. Macnamara gives reasons for believing
that the inhabitants of districts subject to malaria are apt to be
sterile; but this cannot apply in several of the above cases. Some
writers have suggested that the aborigines of islands have suffered in
fertility and health from long continued interbreeding; but in the
above cases infertility has coincided too closely with the arrival
of Europeans for us to admit this explanation. Nor have we at
present any reason to believe that man is highly sensitive to the evil
effects of inter-breeding, especially in areas so large as New
Zealand, and the Sandwich archipelago with its diversified stations.
On the contrary, it is known that the present inhabitants of Norfolk
Island are nearly all cousins or near relations, as are the Todas in
India, and the inhabitants of some of the Western Islands of Scotland;
and yet they seem not to have suffered in fertility.*

  * On the close relationship of the Norfolk Islanders, Sir W.
Denison, Varieties of Vice-Regal Life: vol. i., 1870, p. 410. For
the Todas, see Col. Marshall's work 1873, p. 110. For the Western
Islands of Scotland, Dr. Mitchell, Edinburgh Medical Journal, March to
June, 1865.

  A much more probable view is suggested by the analogy of the lower
animals. The reproductive system can be shewn to be susceptible to
an extraordinary degree (though why we know not) to changed conditions
of life; and this susceptibility leads both to beneficial and to
evil results. A large collection of facts on this subject is given
in chap. xviii. of vol. ii. of my Variation of Animals and Plants
under Domestication, I can here give only the briefest abstract; and
every one interested in the subject may consult the above work. Very
slight changes increase the health, vigour, and fertility of most or
all organic beings, whilst other changes are known to render a large
number of animals sterile. One of the most familiar cases, is that
of tamed elephants not breeding in India; though they often breed in
Ava, where the females are allowed to roam about the forests to some
extent, and are thus placed under more natural conditions. The case of
various American monkeys, both sexes of which have been kept for
many years together in their own countries, and yet have very rarely
or never bred, is a more apposite instance, because of their
relationship to man. It is remarkable how slight a change in the
conditions often induces sterility in a wild animal when captured; and
this is the more strange as all our domesticated animals have become
more fertile than they were in a state of nature; and some of them can
resist the most unnatural conditions with undiminished fertility.*
Certain groups of animals are much more liable than others to be
affected by captivity; and generally all the species of the same group
are affected in the same manner. But sometimes a single species in a
group is rendered sterile, whilst the others are not so; on the
other hand, a single species may retain its fertility whilst most of
the others fail to breed. The males and females of some species when
confined, or when allowed to live almost, but not quite free, in their
native country, never unite; others thus circumstanced frequently
unite but never produce offspring; others again produce some
offspring, but fewer than in a state of nature; and as bearing on
the above cases of man, it is important to remark that the young are
apt to be weak and sickly, or malformed, and to perish at an early
age.

  * For the evidence on this head, see Variation of Animals, &c., vol.
ii., p. 111.