persecuted by man as long as, or longer than, any bird now existing on
the globe. If fear of man ever becomes hereditary in birds, we ought
certainly to find some trace of such an instinct in this species. I have
been unable to detect any, though I have observed scores of young rheas
in captivity, taken before the parent bird had taught them what to fear.
I also once kept a brood myself, captured just after they had hatched
out. With regard to food they were almost, or perhaps quite,
independent, spending most of the time catching flies, grasshoppers, and
other insects with surprising dexterity; but of the dangers encompassing
the young rhea they knew absolutely frothing. They would follow me about
as if they took me for their parent; and, whenever I imitated the loud
snorting or rasping warning-call emitted the old bird in moments of
danger, they would to me in the greatest terror, though no animal was in
sight, and, squatting at my feet, endeavour to conceal themselves by
thrusting their heads and long necks up my trousers. If I had caused a
person to dress in white or yellow clothes for several consecutive days,
and had then uttered the warning cry each time he showed himself to the
birds, I have no doubt that they would soon have acquired a habit of
running in terror from him, even without the warning cry, and that the
fear of a person in white or yellow would have continued all their
lives. Up to within about twenty years ago, rheas were seldom or never
shot in La Plata and Patagonia, but were always hunted on horseback and
caught with the bolas. The sight of a mounted man would set them off at
once, while a person on foot could walk quite openly to within easy
shooting distance of them; yet their fear of a horseman dates only two
hundred years back--a very short time, when we consider that, before the
Indian borrowed the horse from the invader, he must have systematically
pursued the rhea on foot for centuries. The rhea changed its habits when
the hunter changed his, and now, if an _estanciero_ puts down ostrich
hunting on his estate, in a very few years the birds, although wild