Our ordinary races of sheep only give birth once a year to a single lamb; the “hong-ti” twice a year to two lambs each time. The wild sow only litters once a year with but six or eight young, but when domesticated litters twice a year with from ten to fifteen. Her fecundity is therefore at least tripled. In the Indian pig, derived from the “Aperea,” it is more than seven times as great.
In dogs, habits imposed by education, transmitted and strengthened by heredity, finally assume the appearance of so many natural instincts by which races are as nicely characterised as by physical peculiarities. This has been established beyond a doubt by the experiments carried on by Knight during more than thirty years. The mention of the beagle and the pointer will be sufficient to recall the contrast which in many cases exists between these acquired instincts. Considered as the relative development of the intelligence, properly so called, the difference between races is also very marked in many cases. From this point of view we need only compare the greyhound and the spaniel.
V. If from animals and plants we pass to man, we shall find in him, as in the two inferior kingdoms, groups distinguished by anatomical, physiological and psychological differences. In most cases the same organs and the same functions present analogous modifications. What reason can be alleged for the idea that, if their nature is considered, these differences and modifications have a greater signification in man, and that they characterise species and not race? Clearly none; it would be reasoning against the laws of analogy. An argument based upon the variations presented by the manifestations of morality and religion, would be a neglect of the fact that these faculties are the attributes of the human kingdom, that they are wanting in the other kingdoms, and are not in consequence susceptible of any comparison of this kind. In that which is exclusively human, man can only be compared with man.
In conclusion, the facts of the variations and differences existing in man between different groups, are of the same nature as those established between different races of animals and plants. The nature of these phenomena cannot then be brought forward as an argument in favour of the theory that these groups are so many species.
CHAPTER V.
EXTENT OF VARIATIONS IN ANIMAL AND VEGETABLE RACES; APPLICATION TO MAN.
I. The question to which this chapter is devoted is one of those which I shall treat most fully in this course. In fact, it has a special importance. Nearly all the polygenistic arguments are included in the following:—“The difference between the Negro and the White is too great for them to belong to the same species.” These types are the two extremes in the human series. Therefore, if it can be shown that between the two extremes, the limits of variation are almost always greater in plants and animals than in man, we shall have undermined the foundation of the whole polygenistic doctrine.
Now, even if we leave plants out of the question, and there can be little doubt in respect to them; if we merely compare man and animals, organ for organ, function for function, we shall have no great difficulty in arriving at the conclusion, that this is really the case; so much so that we shall be led to ask the question, why the variability is less in man than in animals. The complete demonstration of this general fact would require more extended treatment than I am able to give. I shall, therefore, confine myself to citing some examples.
II. The colouring of the skin is one of the most striking characteristics, and one which is most apparent to the eye. This has given rise to the expressions White, Yellow, and Black, which are most improperly used to designate the three fundamental groups of mankind. We will first prove that these names possess the grave inconvenience of giving rise to ideas which are entirely erroneous. Amongst the Whites there are entire populations, whose skin is as black as that of the darkest Negro. I shall only quote the Bishareen and other tribes inhabiting the African coasts of the Red Sea, the black Moors of Senegal, etc. On the other hand, there are yellow Negroes, as the Bosjesmans, who are the colour of light mahogany, or of café au lait, as Livingstone tells us.
It is no less true that colour is by far the most variable characteristic in man, and when we place the coal black Negro side by side with the fair White with his pinkish complexion, the contrast is striking. But this contrast is repeated in several races of animals, in the dog, for example, whose skin is generally blackish, but white in the white poodle. It is the same among horses, a fact which was known even to Herodotus, who pronounces white horses with a black skin as superior to all others.