African Nature Notes and Reminiscences 2
The most conspicuous colors of nature, for instance, are, under
ordinary circumstances, black and white. Yet we continually find
black, and sometimes white, animals thriving as well as their more
dull-colored compeers under conditions that certainly seem as if they
ought to favor the latter. The white goat of the Rocky Mountains may
be helped by its coloration in winter, but in summer its white coat
advertises its presence to every man or beast within range of vision,
and this at the very time when the little white kids are most in need
of protection. Eagles are formidable foes of these little kids, and
undoubtedly their white color is a disadvantage to them in the struggle
for existence, when they are compared with the dull-colored lambs
of the mountain sheep of the same general habitat. The sheep tend
to become mainly or entirely white at the northern portion of their
range--thereby becoming exceedingly conspicuous in summer--but change
to grays and browns from the semi-Arctic regions southward. The goats,
however, remain white everywhere.
Again, birds and mammals of the far North tend to be white, but one
of the typical far northern birds is the jet black raven. It is hard
to believe that the color of the snowy owl assists it in getting
its prey, or that its color hampers the raven. The northern weasels
and northern hares of America both turn white in winter. Thru most
of their range the various species of these weasels and hares exist
side by side with the close kinsmen of the weasel, the mink and the
sable, and at the southern boundary of their range side by side with
the small gray rabbits; none of which change their color any more than
the lynx and fox do, and yet in the struggle for life seem to be put
to no disadvantage thereby. The Arctic hare changes color as does the
ptarmigan. The ordinary snow-shoe rabbits and jack-rabbits of the woods
and plains south of the Arctic hare region also change their color;
but the grouse which inhabit the same woods or open plains, such as
the ruffed, the sharp-tailed and the spruce, unlike their northern
kinsman, the ptarmigan, undergo no seasonal change. Around my ranch
on the Little Missouri, the jack-rabbits all turned white in winter;
the little cotton-tail rabbits did not; yet as far as I could see both
species were equally at home and fared equally well.
When a boy, shooting on the edges of the desert in Egypt, I was imprest
with the fact that the sand grouse, rosy bullfinches, sand larks and
sand chats all in the coloration of their upper parts harmonized
strikingly with the surroundings, while the bold black and white
chats were peculiarly noticeable, and yet as far as I could see held
their own as well in the struggle for existence. But as regards the
first-named birds it seemed to me at the time that their coloration was
probably protective, for in the breeding season the males of some of
them showed striking colors, but always underneath, where they would
not attract the attention of foes.
Mr. Selous also shows that the "signal" or "mutual recognition"
theory of coloration has been at the least carried to an extreme by
closet naturalists. The prongbuck of North America has the power
of erecting the glistening white hairs on its rump until it looks
like a chrysanthemum; but there seems scarcely any need of this as
a signal; for prongbucks live out on the bare plains, never seek to
avoid observation, are very conspicuous beasts, and have eyes like
telescopes, so that one of them can easily see another a mile or
two off. According to my experience--but of course the experience
of any one man is of limited value, and affords little ground for
generalization--the "chrysanthemum" is shown when the beast is much
aroused by curiosity or excitement.
Mr. Selous' chapters on the lion possess a peculiar interest, for they
represent without any exception the best study we have of the great,
tawny, maned cat. No one observer can possibly cover the entire ground
in a case such as this, for individual animals differ markedly from one
another in many essential traits, and all the animals of one species
in one locality sometimes differ markedly from all the animals of the
same species in another locality (as I have myself found, in some
extraordinary particulars, in the case of the grizzly bear). Therefore,
especially with a beast like the lion, one of the most interesting of
all beasts, it is necessary for the naturalist to have at hand the
observations of many different men; but no other single observer has
left a record of the lion of such value to the naturalist as Mr. Selous.
One of the most interesting of Mr. Selous' chapters is that containing
his notes on wild dogs, on hunting hounds, and on cheetahs. Especially
noteworthy are his experiences in actually running down and overtaking
by sheer speed of horse and hound both the wild dog and the cheetah.
These experiences are literally inexplicable with our present
knowledge; and therefore it is all the more valuable to have them
recorded, Mr. Selous' own account of the speed of wild dogs and the
statements of many competent observers about cheetahs--as for instance,
of that mighty hunter, Sir Samuel Baker--make it clear that under
ordinary circumstances both wild dogs and cheetahs, when running after
their game, go at a speed far surpassing that of a horse. Yet in these
instances given by Mr. Selous, he and his companions with their camp
dogs once fairly ran down a pack of wild dogs; and twice he fairly
ran down full-grown cheetahs. In the last case it is possible that
the hunted cheetah, not at first realizing his danger, did not put
forth his full speed at the beginning, and, not being a long-winded
animal, was exhausted and unable to spurt when he really discovered his
peril. But with the hunting dogs it is hard to imagine any explanation
unless they were gorged with food. In coursing wolves with greyhounds,
I have noticed that the dogs will speedily run into even an old dog
wolf, if he is found lying by a carcase on which he has feasted, under
conditions which would almost certainly have insured his escape if
he had been in good running trim. I once saw a cougar, an old male,
jump from a ledge of rock surrounded by hounds and come down hill for
several hundred yards thru the snow. The hounds started almost on even
terms with him, but he drew away from them at once, and when he reached
the bottom of the hill, was a good distance ahead; but by this time
he had shot his bolt, and after going up hill for a very few yards
he climbed into a low evergreen tree, which I reached almost as soon
as the hounds. His lungs were then working like bellows, and it was
obvious he could have gone no distance further.
The book of nature has many difficult passages, and some of them seem
mutually contradictory. It is a good thing to have capable observers
who can record faithfully what they find therein, and who are not in
the least afraid of putting down two observations which are in seeming
conflict. Allied species often differ so radically in their habits
that, with our present knowledge, not even a guess can be made as to
the reason for the difference; this makes it all the more necessary
that there should be a multitude of trustworthy observations. Mr.
Selous points out, for instance, the extraordinary difference in
pugnacity between the fighting roan and sable antelopes, on the one
hand, and on the other, the koodoo and the mild eland. There is quite
as great difference between far more closely allied species, or even
between individuals of one species in one place and those of the same
species in another place. Sometimes the reasons for the difference are
apparent; all carnivores in India, with its dense, feeble population,
would at times naturally take to man-killing. In other cases, at least
a guess may be hazarded. The wolf of America has never been dangerous
to man, as his no larger or more formidable brother of Asia and Europe
has been from time immemorial; yet the difference may be accounted for
by the difference of environment. But it is hard to say why the cougar,
which is just about the size of the great spotted cats, and which preys
on practically the same animals, should not be dangerous to man, while
they are singularly formidable fighters when at bay. The largest cougar
I ever killed was eight feet long and weighed over two hundred pounds.
Very few African leopards or Indian panthers would surpass these
measurements, and this particular animal had been preying not only on
deer, but on horses and cattle; yet I killed him with no danger to
myself, under circumstances which would probably have insured a charge
from one of the big spotted cats of Africa or Asia, or, for the matter
of that, from a South American jaguar. And by the way, in reading of
the ravages committed by leopards among the hounds of the sport-loving
planters of Ceylon, it has always seemed to me strange that these
planters did not turn the tables on the aggressors by training packs
especially to hunt them. Such a pack as that with which I have hunted
the cougar and the black bear in the Rocky Mountains would, I am sure,
give a good account of any leopard or panther that ever lived. All that
would be needed would be a good pack of trained hounds and six or eight
first-class fighting dogs in order, as I thoroughly believe, completely
to clear out the leopard from any given locality.
Mr. Selous' notes on the Cape buffalo and tsetse fly are extremely
interesting. But indeed this is true of all that he has written,
both of the great game beasts themselves and of his adventures in
hunting them. His book is a genuine contribution alike to hunting
lore and to natural history. It should be welcomed by every lover of
the chase and by every man who cares for the wild, free life of the
wilderness. It should be no less welcome to all who are interested in
the life-histories of the most formidable and interesting of the beasts
that dwell in our world to-day.
THEODORE ROOSEVELT.
THE WHITE HOUSE,
_May 23, 1907_.
CONTENTS
CHAPTER I
NOTES ON THE QUESTIONS OF PROTECTIVE COLORATION, RECOGNITION MARKS,
AND THE INFLUENCE OF ENVIRONMENT ON LIVING ORGANISMS
Harmony of colour in nature--Theory of protective coloration--Sexual
selection--Conspicuous colours not harmful--The influence of
environment--The leucoryx--The Barbary sheep--The Sardinian
moufflon--African butterflies--Coloration of the musk ox
and caribou--Arctic hares and foxes--Coloration of mammals
in the Yukon Territory--The chamois in winter--Examples of
conspicuous coloration in African mammals--Colour not always
protective--Carnivorous animals usually hunt by scent--Wild
dogs and wolves--Wild dog and sable antelope--Sense of smell
in herbivorous animals--Sight of antelopes--Experience with
waterbuck--Dull sight of caribou--Demeanour of wild animals when
alarmed--Small antelopes--Lions--Large antelopes--Difficulty of
seeing wild animals sometimes exaggerated--Powers of sight of
Bushmen--Colour not protective against animals which hunt by
night and by scent--Animals in motion easy to see--Restlessness
of wild animals--Lions attacking bullocks--Zebras the principal
prey of lions since the disappearance of buffaloes--Appearance of
zebras--Undoubtedly conspicuous animals in open country--Zebras
by moonlight--Strong smell of zebras--Conspicuous antelopes in
East Africa--Effect of the juxtaposition of black and white--Bold coloration of the sable antelope
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