On
the stony plateaus of the Andes, and on the most barren spots in
Patagonia, where no other bird is seen, there are small species of
Synallaxis, which, in their obscure colour and motions on the ground,
resemble mice rather than birds; indeed, the Quichua name for one of
these Synallaxes is _ukatchtuka,_ or mouse-bird. How different is the
life habit here from what we see in the tropical groups--the large birds
with immense beaks, that run vertically on the trunks of the great
forest trees!
At the extreme southern extremity of the South American continent we
find several species of Cin-clodes, seeking a subsistence like
sandpipers on the beach; they also fly out to sea, and run about on the
floating kelp, exploring the fronds for the small marine animals on
which they live. In the dreary forests of Tierra del Fuego another
creeper, Uxyurus, is by far the commonest bird. "Whether high up or low
down, in the most gloomy, wet, and scarcely penetrable ravines," says
Darwin, "this little bird is to be met with;" and Dr. Cunningham also
relates that in these wintry, savage woods he was always attended in his
walks by parties of these little creepers, which assembled to follow him
out of curiosity.
To birds placed at so great a disadvantage, by a feeble flight and other
adverse circumstances, in the race of life bright colours would
certainly prove fatal. It is true that brown is not in itself a
protective colour, and the clear, almost silky browns and bright
chestnut tints in several species are certainly not protective; but
these species are sufficiently protected in other ways, and can afford
to be without a strictly adaptive colour, so long as they are not
conspicuous.
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