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development of species with a many facetted spheroid tumbling over from one facet, or stable equilibrium, to another. The existence of internal conditions in animals corresponding with such facets is denied by pure Darwinians, but it is contended in this work, though not in this chapter, that something may also be said for their existence.
The considerations brought forward in the last two chapters, namely, the difficulties with regard to incipient and closely similar structures respectively, together with palæontological considerations to be noticed later, appear to point strongly in the direction of sudden and considerable changes. This is notably the case as regards the young oysters already mentioned, which were taken from tlie shores of England and placed in the Mediterranean, and which at once altered their mode of growth and formed prominent diverging rays, like those of the proper Mediterranean oyster; as also the twenty-nine kinds of American trees, all differing from their nearest European allies similarly—“leaves less toothed, buds and seeds smaller, fewer branchlets,” &c. To these may be added other facts given by Mr. Darwin. Thus he says " that climate, to a certain extent, directly modifies the form of dogs.” 1
The Rev. R. Everett found that setters at Delhi, though most carefully paired, yet had young with “nostrils more contracted, noses more pointed, size inferior, and limbs more slender.” Again, cats at Mombas, on the coast of Africa, have short stiff hairs instead of fur; and a cat at Algoa Bay, when left only eight weeks at Mombas, “underwent a complete metamorphosis, having parted with its
1 “Animals and Plants under Domestication,” vol. i. p. 37.
sandy-coloured fur."1 The conditions of life seem to produce a considerable effect on horses, and instances are given by Mr. Darwin of pony breeds 2 having independently arisen in different parts of the world, possessing a certain similarity in their physical conditions. Also changes due to climate may be brought about at once in a second generation, though no appreciable modification is shown by the first. Thus “Sir Charles Lyell mentions that some Englishmen, engaged in conducting the operations of the Real del Monte Company in Mexico, carried out with them some greyhounds of the best breed to hunt the hares which abound in that country. It was found that the greyhounds could not support the fatigues of a long chase in this attenuated atmosphere, and before they could come up with their prey they lay down gasping for breath; but these same animals have produced wlielps, which have grown up, and are not in the least degree incommoded by the want of density in the air, but run down the hares with as much ease as do the fleetest of their race in this country." 3
1 “Animals and Plants under Domestication,” vol. i. p. 47. 2 Ibid. p. 52.
3 Carpenter's “Comparative Physiology,” p. 987, quoted by Mr. J. J. Murphy, “Habit and Intelligence,” vol. i. p. 171. Mr. Darwin, in his “ Descent of Man," vol. i. p. 119, mentions that certain South American Indians (Aymaras), inhabiting a lofty region, have remarkably long bodies and short legs-especially the femora. He adds: “These men are so thoroughly acclimatized to their cold and lofty abode, that when carried down by the Spaniards to the low eastern plains, and when now tempted down by high wages to the gold-washings, they suffer a frightful rate of mortality. Nevertheless, Mr. Forbes found a few pure families which had survived during two generations; and he observed that they still inherited their characteristic peculiarities. But it was manifest, even without measurement, that these peculiarities had all decreased ; and, on measurement, their bodies were found not to be so much elongated as
We have here no action of “Natural Selection;" it was not that certain puppies happened accidentally to be capable of enduring more rarefied air, and so survived, but the offspring were directly modified by the action of surrounding conditions. Neither was the change elaborated by minute modifications in many successive generations, but appeared at once in the second.
Further, with regard to sudden alterations of form, Nathusius is said to state positively as to pigs, that the result of common experience and of his experiments was that rich and abundant food, given during youth, tends by some direct action to make the head broader and shorter. Curious jaw appendages often characterize Normandy pigs, according to M. Eudes Deslongchamps. Richardson figures these appendages on the old “Irish greyhound pig," and they are said by Nathusius to appear occasionally in all the long-eared races. Mr. Darwin observes, “As no wild pigs are known to have analogous appendages, we have at present no reason to suppose that their appearance is due to reversion ; and if this be so, we are forced to admit that somewhat complex, though apparently useless structures may be suddenly developed without the aid of selection.” Again, “ Climate directly affects the thickness
those of the men on the high plateau ; whilst their femora had become somewhat lengthened, as had their tibiæ, but in a less degree.” Here the rapidity of the change--only two generations-points rather to a direct action of conditions than to that of “Natural Selection.” In favour of direct modification, another passage from Mr. Darwin may be quoted. He says, “In young persons whose heads from disease have become fixed either sideways or backways, one of the eyes has changed its position, and the bones of the skull have been modified.”- Descent of Man, vol. i.
“ Animals and Plants under Domestication," vol. i. p. 72. 3 Ibid. p. 76.
of the skin and hair" of cattle. In the English climate an individual Porto Santo rabbit ? recovered the proper colour of its fur in rather less than four years. The effect of the climate of India on the turkey is considerable. Mr. Blyth 3 describes that bird as being much degenerated in size, “utterly incapable of rising on the wing,” of a black colour, and “with long pendulous appendages over the beak enormously developed.” Mr. Darwin again tells us that there has suddenly appeared in a bed of common broccoli a peculiar variety, faithfully transmitting its newly acquired and remarkable characters ; 4 also that there has been a rapid transformation of American varieties of maize; 5 that certainly “the Ancon and Manchamp breeds of sheep," and that all but certainly) Niata cattle, turnspit and pug dogs, jumper and frizzled fowls, short-faced tumbler pigeons, hook-billed ducks, &c., and a multitude of vegetable varieties, have suddenly appeared in nearly the same state as we now see them.“ Lastly, Mr. Darwin tells us, that there has been an occasional development (in five distinct cases) in England of the “japanned” or “black-shouldered peacock” (Pavo nigripennis); a distinct species, according to Dr. Sclater, yet arising in Sir J. Trevelyan's flock composed entirely of the common kind, and increasing, “ to the extinction of the previously existing breed.” Mr. Darwin's only explanation of the phenomenon (on the supposition of the species being distinct) is by reversion, owing to a supposed
1 "Animals and Plants under Domestication,” vol. i. P.
71. 2 Ibid. p. 114.
Quoted, Ibid. p. 274. 4 Ibid. p. 324. 5 Ibid. p. 322,
6 Ibid. vol. ii. p. 414. ? Proc. Zool. Soc. of London, April 24, 1860. 8 “Animals and Plants under Domestication,” vol. i. p. 291.
ancestral cross. But he candidly admits, "I have heard of no other such case in the animal or vegetable kingdom.” On the hypothesis of its being only a variety, he observes,
The case is the most remarkable ever recorded of the abrupt appearance of a new form, which so closely resembles a true species that it has deceived one of the most experienced of living ornithologists.”
As to plants, M. C. Naudin has given the following instances of the sudden origination of apparently permanent forms: “The first case mentioned is that of a poppy, which took on a remarkable variation in its fruit-a crown of secondary capsules being added to the normal central capsule. A field of such poppies was grown, and M. Göppert, with seed from this field, obtained still this monstrous form in great quantity. Deformities of ferns are sometimes sought after by fern-growers. They are now always obtained by taking spores from the abnormal parts of the monstrous fern; from which spores ferns presenting the same peculiarities invariably grow.
The most remarkable case is that observed by Dr. Godron, of Nancy. In 1861 that botanist observed, amongst a sowing of Datura tatula, the fruits of which are very spinous, a single individual of which the capsule was perfectly smooth. The seeds taken from this plant all furnished plants having the character of this individual. The fifth and sixth generations are now growing without exhibiting the least tendency to revert to the spinous form.
remarkablestill, when crossed with the normal Datura tatula, hybrids were produced, which, in the
1 Extracted by J. J. Murphy, vol. i. p. 197, from the Quarterly Journal of Science, of October 1867, p. 527.