Degeneration: A Chapter in DarwinismMacmillan and Company, 1880 - 75 páginas |
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Términos y frases comunes
admitted adult form adult structure animalcules ape-like ancestors appear Ascidian tadpole atrophy axolotl BALFOUR STEWART Barnacle become body BRAIN MOUTH branch breeder cerebral eye civilised cloaca common frog compared complex condition creature Crown 8vo Crustacean Darwin Darwinian theory degene egg-cell elaborate embryo evidence evolution exhibit explanation F.R.S. With Illustrations fact family-tree forms of animals genealogical tree gill-slits gills gradually guess hypothesis of degeneration individual instance of Degeneration intestine kind knowledge language LARVA lative legs LEPAS Lernæocera living things MACMILLAN modified descendants Molluscs myelonic natural selection naturalists Nauplius NOTOCHORD numerous Illustrations observation order of nature organs original Owens College pair of limbs parasitic pedigree Peneus Phallusia Phantasie phases possible present day produce Professor question recapitulative represent retina Rotifers Sacculina scientific shrimp simpler SIR JOHN LUBBOCK SLITS soul species SPIRACLE struggle for existence super-larvation supposed tail theologian tion true truth varieties Vertebrates whilst worm young Ascidian
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Página 33 - Any new set of conditions occurring to an animal which render its food and safety very easily attained, seem to lead as a rule to Degeneration; just as an active healthy man sometimes degenerates when he becomes suddenly possessed of a fortune; or as Rome degenerated when possessed of the riches of the ancient world. The habit of parasitism clearly acts upon animal organisation in this way. Let the parasitic life once be secured, and away go legs, jaws, eyes, and ears; the active, highly-gifted crab,...
Página 65 - Verstandes sowohl, als der erweiternden und zum Allgemeinen strebenden Phantasie sind dem Naturforscher in einem harmonischen Wechselwirken nothwendig. Durch Störung dieses Gleichgewichts wird der Naturforscher von der Phantasie zu Träumereien hingerissen, während diese Gabe den talentvollen Naturforscher von hinreichender Verstandesstärke zu den wichtigsten Entdeckungen führt.
Página 9 - Nature gives no reply to a general inquiry — she must be interrogated by questions which already contain the answer she is to give ; in other words, the observer can only observe that which he is led by hypothesis to look for...
Página 30 - It is the more remarkable whilst the possibility of a degeneration — a loss of organisation making the descendant far simpler or lower in structure than its ancestor — has been admitted for a few exceptional animals, that the same hypothesis should not have been applied to the explanation of other simple forms of animals. The hypothesis of Degeneration will, I believe, be found to render most valuable service in pointing out the true relationships of animals which arc a puzzle and a mystery when...
Página 33 - Any new set of conditions," says Ray Lankester, " occurring to an animal which render its food and safety very easily attained, seem to lead as a rule to degeneration ; just as an active healthy man sometimes degenerates when he becomes suddenly possessed of a fortune ; or as Rome degenerated when possessed of the riches of the ancient world. The habit of parasitism clearly acts upon animal organization in this way.