This emergency must
have occurred for ages, and it, again, called only for the first step
from cause to effect, and called for the use of no intermediate agent.
If the robin were to hold a leaf or a branch above his mate at such
times, that would imply reflection.

It is said that elephants in India will besmear themselves with mud as
a protection against insects, and that they will break branches from
the trees and use them to brush away the flies. If this is true, it
shows, I think, something beyond instinct in the elephant; it shows
reflection.

All birds are secretive about their nests, and display great cunning
in hiding them; but whether they know the value of adaptive material,
such as moss, lichens, and dried grass, in helping to conceal them,
admits of doubt, because they so often use the results of our own
arts, as paper, rags, strings, tinsel, in such a reckless way. In a
perfectly wild state they use natural material because it is the
handiest and there is really no other. The phoebe uses the moss on
or near the rocks where she builds; the sparrows, the bobolinks, and
the meadowlarks use the dry grass of the bank or of the meadow bottom
where the nest is placed.

The English writer to whom I have referred says that the wren builds
the outside of its nest of old hay straws when placing it in the side
of a rick, of green moss when it is situated in a mossy bank, and of
dead leaves when in a hedge-row or a bramble-bush, in each case thus
rendering the nest very difficult of detection because it harmonizes
so perfectly with its surroundings, and the writer wonders if this
harmony is the result of accident or of design. He is inclined to
think that it is unpremeditated, as I myself do. The bird uses the
material nearest to hand.

Another case, which this same writer gives at second-hand, of a bird
recognizing the value of protective coloration, is not credible. A
friend of his told him that he had once visited a colony of terns "on
an island where the natural breeding accommodation was so limited that
many of them had conveyed patches of pebbles on to the grass and laid
their eggs thereon."

Here is the same difficulty we have encountered before--one more step
of reasoning than the bird is capable of. As a deduction from observed
facts, a bird, of course, knows nothing about protective coloring; its
wisdom in this respect is the wisdom of Nature, and Nature in animal
life never acts with this kind of fores