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OF THE ACCOMMODATING POWER OF INSTINCT, AND INFERENCES FROM THE FACTS.
In the preceding Chapter, I have spoken of pure Instincts, which act without any instruction, prior to all experience. I have also spoken of the natural senses and their perfection in man and the brutes, as well as of some anomalous acts of the latter exhibited in their migrations; and have lastly given some examples of the higher qualities in the minds of brutes, which are depending on instruction and education, like human reason. I shall now very briefly notice another train of actions or modified instincts, if they may be so called, in which the brutes, without instruction from man, appear to deviate in some degree from the unerring rule of Instinct, and adapt their conduct to circumstances. Dr. Darwin is very anxious to prove that these deviations arise from a reasoning faculty.
We are told by Adanson, that Rabbits in the island of Sor, near Senegal, do not burrow in the earth;
hence Dr. Darwin suspects that their digging themselves houses in this cold climate is an acquired art.
In Senegal, where the heat is great, the Ostrich neglects her eggs during the day, but sits upon them in the night. At the Cape of Good Hope, however, where the heat is less, she sits upon her eggs, both day and night.
It is said that the Bees that were taken to Barbadoes and other islands of the West Indies, ceased to lay up honey after the first year, as they found it not useful to them; and are now become very troublesome to the inhabitants, by infesting their sugar houses.
In Jamaica, however, they continue to make honey, as the cold north winds or rainy seasons of that island confine them at home, for several weeks together.
And the Bees of Senegal, which differ from those of Europe only in size, make their honey not only superior to ours in delicacy of flavour, but it has this singularity, that it never concretes but remains liquid as syrup.
This accommodating variation in the instinct of the bee, may, however, be partly explained by the operation of human intercourse. Because, if the bees had not sugar houses or some other large depositories of this sweet substance to resort to, it is most probable, they would make honey in the usual way. And the difference in the qualities of the honey in Senegal from our own, may be referable to a difference in the flowers from which it is collected.
that even in England and Ireland, the honey made in one district frequently differs in flavour, and sometimes in other qualities, from that made in another.
The Wasp of this country fixes his habitation under ground, that he may not be affected with the various changes of our climate; but in Jamaica he hangs it on the bough of a tree, where the seasons are less
Loubiere, in his history of Siam, says, "That in a part of that kingdom, which lies open to great inundations, all the Ants make their settlements upon trees; no ants' nests are to be seen any where else." Whereas in our country the ground is their only situation.
In countries infested with monkies, birds, which in other climates build in bushes and clefts of trees, suspend their nests on slender twigs, and thus elude their enemies. The same species of birds build their nests differently, when climate and circumstances require it. (Rees' Cyclop.)
Dr. Darwin has collected many facts to show that the Cuckoo in some places hatches and educates her own young while in others, she builds no nest, but uses that of some lesser bird, as the wagtail or hedge sparrow, and depositing one egg in it, takes no further care of her progeny.
The Swallow sometimes migratès; sometimes is found torpid in the hollow of rocks, and even under water. Other birds migrate from some countries and remain stationary in others; as is the case with
certain animals. So that emigrations would seem to depend on want of food, inclement seasons, or unfriendly climates.
Ulloa mentions that in Juan Fernandes the Dogs did not attempt to bark, till some European dogs were put among them; and then they gradually began to imitate them; but in a strange manner at first, as if they were learning a thing that was not natural to them. Linnæus, indeed, observes, that the dogs of South America do not bark at strangers; and the European dogs, carried to Guinea, are said in three or four generations to cease to bark, and only howl like the dogs, natives of that coast.
From some of these and other similar facts, Dr. Darwin contends, "That the migrations of birds are not instinctive, but accidental improvements, like the arts among mankind, taught by their contemporaries, or delivered by tradition :-that the arts of bees, wasps, and ants, if we were better acquainted with their histories, have arisen in the same manner from experience and tradition, as the arts of our own species; though their reasoning is from fewer ideas." "And, that as animals seem to have undergone great changes, as well as the inanimate parts of the earth, and are probably still in a state of gradual improvement, it is not unreasonable to conclude, that some of the actions, both of large animals and of insects, may have been acquired in a state preceding the present one; and have been derived from the parents to their offspring by imitation or other kind
of tradition :-For that, as the eggs of the crocodile are hatched by the sun, and the eggs of insects and spawn of fish, by the vernal warmth, this might have been the case with birds in warm climates, in their early state, and they might have learned to incubate their eggs, as they became more perfect animals, or removed into colder climates."*
Dr. Darwin was possessed of uncommon genius, and yet one would wonder that any man of scientific observation would give the authority of his name to such opinions. He certainly carries the notion of a reasoning or adapting power in insects and brutes, to the very extreme of that hypothesis. According to it, the lower animals have no instinct at all; but experience and observation determine all their actions; and it must appear strange, that while many eminent philosophers maintain that the human infant could not subsist without its instincts; by this hypothesis, the lower animals should all be guided in every case by reason. The error seems to lie in confounding all the motive powers and faculties of brutes together; so that instinct, and sensation, and memory, and imitation, and feeling, as gratitude and revenge, are all resolvable into reason. This is as absurd, as to resolve them all into instinct.
It is much more consistent with the nature of all the various phenomena we have been considering, to suppose
Sce Temple of Nature, Notes, 40.