On first considering the question of the origin of the rat-goat of Majorca, some naturalists will, no doubt, be tempted to suggest that it is a case of a sudden "sport," a "mutation" as they now call it, and not a result of gradual slowly developed reduction of the now lost teeth and correspondingly gradual enlargement of the two middle ones, taking many thousand generations to bring about. The fact that the rat-goat is found on an island cut off from competition with other animals will favour this view. On the other hand, there is the important and really remarkable fact that familiar as man has been for ages with Ruminants of many kinds—such as sheep, goats, cattle, deer—there is absolutely no case on record of an "oddity" or "monstrosity" resembling the rat-goat's condition occurring in the teeth of any of the hundreds of thousands of these animals killed and eaten by man, and therefore closely examined. Professor Bateson, who a few years ago ransacked the museums of Europe for instances of "discontinuous variation," or "sports," and wrote a valuable book on the subject, did not discover any example of the kind. Apart from the view, which is very generally held, that such sudden "mutations" as "rat-teeth in a ruminant" are—even should they occur—not perpetuated, we are not really in any way driven to suppose that the rat-goat of Majorca originated in that island. It is true that we know nothing like it in the Pliocene and Miocene of the Mediterranean region which could have been its immediate ancestor. But probably the ancestors of the rat-goat were slowly developed from a Miocene sheath-horned ruminant, a primitive sort of antelope in some part of North-west Africa, or in an extension of it now submerged in the Atlantic, and stragglers of this curious and now lost Ruminant stock were left in Majorca when in Miocene or early Pliocene times that island became detached from its Hispano-African connection.
CHAPTER VIII
VEGETARIANS AND THEIR TEETH
No mistake, said Huxley, is more frequently made by clever people than that of supposing that a cause or an opinion is unsound because the arguments put forward in its favour by its advocates are foolish or erroneous. Some of the arguments put forward in favour of the exclusive use by mankind of a vegetable diet can be shown to be based on misconception and error, and I propose now to mention one or two of these. But I wish to guard against the supposition that I am convinced in consequence that animal substances form the best possible diet for man, or that an exclusively vegetable diet may not, if properly selected, be advantageous for a large majority of mankind. That question, as well as the question of the advantage of a mixed diet of animal and vegetable substances, and the best proportion and quantity of the substances so mixed, must be settled, as also the question as to the harm or good in the habitual use of small quantities of alcohol, by definite careful experiment by competent physiologists, conducted on a scale large enough to give conclusive results. The cogency of the arguments in favour of vegetarianism which I am about to discuss is another matter.
In the first place it is very generally asserted by those who advocate a purely vegetable diet that man's teeth are of the shape and pattern which we find in fruit-eating or in root-eating animals allied to him. This is true. The warm-blooded hairy quadrupeds which suckle their young and are called "mammals" (for which word perhaps "beasts" is the nearest Anglo-Saxon equivalent) show in different groups and orders a great variety in their teeth. The birds of to-day have no teeth, the reptiles, amphibians, and fishes have usually simple conical or peg-like teeth, which are used simply for holding and tearing. In some cases the pointed pin-like teeth are broadened out so as to be button-like, and act as crushing organs for breaking up shell-fish. The mammals alone have a great variety and elaboration of the teeth.
Fig. 21.—Side view of the skull of a clouded tiger (Felis nebulosa) to show the teeth. inc. s. The three incisors. can. s. Upper canine, corner-tooth, or dog-tooth. can. i. Lower canine. m. s. The four upper molars or cheek-teeth (called "grinders" in herbivorous animals). m. i. The three lower molars or cheek-teeth.
