Ways of Nature

by John Burroughs

Mr. Wallace even looks upon the nuts as protectively colored, because they are not to be eaten. But without the agency of the birds and the squirrels, how are the heavy nuts, such as the chestnut, beechnut, acorn, butternut, and the like, to be scattered? The blue jay is often busy hours at a time in the fall, planting chestnuts and acorns, and red squirrels carry butternuts and walnuts far from the parent trees, and place them in forked limbs and holes for future use. Of course, many of these fall to the ground and take root. If the protective coloration of the nuts, then, were effective, it would defeat a purpose which every tree and shrub and plant has at heart, namely, the scattering of its seed. I notice that the button-balls on the sycamores are protectively colored also, and certainly they do not crave concealment. It is true that they hang on the naked trees till spring, when no concealment is possible. It is also true that the jays and the crows carry away the chestnuts from the open burrs on the trees where no color scheme would conceal them. But the squirrels find them upon the ground even beneath the snow, being guided, no doubt, by the sense of smell.

The hickory nut is almost white; why does it not seek concealment also? It is just as helpless as the others, and is just as sweet-meated. It occurs to me that birds can do nothing with it on account of its thick shell; it needs, therefore, to attract some four-footed creature that will carry it away from the parent tree, and this is done by the mice and the squirrels. But if this is the reason of its whiteness, there is the dusky butternut and the black walnut, both more or less concealed by their color, and yet having the same need of some creature to scatter them.

The seeds of the maple, and of the ash and the linden, are obscurely colored, and they are winged; hence they do not need the aid of any creature in their dissemination. To say that this is the reason of their dull, unattractive tints would be an explanation on a par with much that one hears about the significance of animal and vegetable coloration. Why is corn so bright colored, and wheat and barley so dull, and rice so white? No doubt there is a reason in each case, but I doubt if that reason has any relation to the surrounding animal life.

The new Botany teaches that the flowers have color and perfume to attract the insects to aid in their fertilization—a need so paramount with all plants, because plants that are fertilized by aid of the wind have very inconspicuous flowers. Is it equally true that the high color of most fruits is to attract some hungry creature to come and eat them and thus scatter the seeds? From the dwarf cornel, or bunch-berry, in the woods, to the red thorn in the fields, every fruit-bearing plant and shrub and tree seems to advertise itself to the passer-by in its bright hues. Apparently there is no other use to the plant of the fleshy pericarp than to serve as a bait or wage for some animal to come and sow its seed. Why, then, should it not take on these alluring colors to help along this end? And yet there comes the thought, may not this scarlet and gold of the berries and tree fruits be the inevitable result of the chemistry of ripening, as it is with the autumn foliage? What benefit to the tree, directly or indirectly, is all this wealth of color of the autumn? Many of the toadstools are highly colored also; how do they profit by it? Many of the shells upon the beach are very showy; to what end? The cherry-birds find the pale ox-hearts as readily as they do the brilliant Murillos, and the dull blue cedar berries and the duller drupes of the lotus are not concealed from them nor from the robins. But it is true that the greenish white grapes in the vineyard do not suffer from the attacks of the birds as do the blue and red ones. The reason probably is that the birds regard them as unripe. The white grape is quite recent, and the birds have not yet "caught on."

Poisonous fruits are also highly colored; to what end? In Bermuda I saw on low bushes great masses of what they called "pigeon-berries" of a brilliant yellow color and very tempting, yet I was assured they were poisonous. It would be interesting to know if anything eats the red berries of our wild turnip or arum. I doubt if any bird or beast could stand them. Wherefore, then, are they so brightly colored? I am also equally curious to know if anything eats the fruit of the red and white baneberry and the blue cohosh.

The seeds of some wild fruit, such as the climbing bitter-sweet, are so soft that it seems impossible they should pass through the gizzard of a bird and not be destroyed.

The fruit of the sumac comes the nearest to being a cheat of anything I know of in nature—a collection of seeds covered with a flannel coat with just a perceptible acid taste, and all highly colored. Unless the seed itself is digested, what is there to tempt the bird to devour it, or to reward it for so doing?

In the tropics one sees fruits that do not become bright colored on ripening, such as the breadfruit, the custard apple, the naseberry, the mango. And tropical foliage never colors up as does the foliage of northern trees.

VI. INSTINCT

Many false notions seem to be current in the popular mind about instinct. Apparently, some of our writers on natural history themes would like to discard the word entirely. Now instinct is not opposed to intelligence; it is intelligence of the unlearned, unconscious kind,—the intelligence innate in nature. We use the word to distinguish a gift or faculty which animals possess, and which is independent of instruction and experience, from the mental equipment of man which depends mainly upon instruction and experience. A man has to be taught to do that which the lower animals do from nature. Hence the animals do not progress in knowledge, while man's progress is almost limitless. A man is an animal born again into a higher spiritual plane. He has lost or shed many of his animal instincts in the process, but he has gained the capacity for great and wonderful improvement.