The worst journey in the world by Apsley Cherry-Garrard

Author:Apsley Cherry-Garrard [Cherry-Garrard, Apsley]
Language: eng
Format: epub
Tags: Biographie, Histoire
ISBN: 9780559086427
Published: 2009-09-15T11:20:55+00:00

PROFESSOR COSSAR EWART'S REPORT

"It was a great disappointment to Dr. Wilson that no Emperor Penguin embryos were obtained during the cruise of the Discovery. But though embryos were conspicuous by their absence in the Emperor eggs brought home by the National Antarctic Expedition, it is well to bear in mind that the naturalists on board the Discovery learned much about the breeding habits of the largest living member of the ancient penguin family. Amongst other things it was ascertained (1) that in the case of the Emperor, as in the King Penguin, the egg during the period of incubation rests on the upper surface of the feet protected and kept in position by a fold of skin from the lower breast; and (2) that in the case of the Emperor the whole process of incubation is carried out on sea ice during the coldest and darkest months of the antarctic winter.

"After devoting much time to the study of penguins Dr. Wilson came to the conclusion that Emperor embryos would throw new light on the origin and history of birds, and decided that if he again found his way to the Antarctic he would make a supreme effort to visit an Emperor rookery during the breeding season. When, and under what conditions, the Cape Crozier rookery was eventually visited and Emperor eggs secured is graphically told in The Winter Journey. The question now arises, Has 'the weirdest bird's-nesting expedition that has ever been made' added appreciably to our knowledge of birds?

"It is admitted that birds are descended from bipedal reptiles which flourished some millions of years ago—reptiles in build not unlike the kangaroo. From Archaeopteryx of Jurassic times we know primeval birds had teeth, three fingers with claws on each hand, and a long lizard-like tail provided with nearly twenty pairs of well-formed true feathers. But unfortunately neither this lizard-tailed bird, nor yet the fossil birds found in America, throw any light on the origin of feathers. Ornithologists and others who have devoted much time to the study of birds have as a rule assumed that feathers were made out of scales, that the scales along the margin of the hand and forearm and along each side of the tail were elongated, frayed and otherwise modified to form the wing and tail quills, and that later other scales were altered to provide a coat capable of preventing loss of heat. But as it happens, a study of the development of feathers affords no evidence that they were made out of scales. There are neither rudiments of scales nor feathers in very young bird embryos. In the youngest of the three Emperor embryos there are, however, feather rudiments in the tail region,—the embryo was probably seven or eight days old—but in the two older embryos there are a countless number of feather rudiments, i.e. of minute pimples known as papillae.

"In penguins as in many other birds there are two distinct crops of feather papillae, viz.: a crop of relatively large papillae which

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