Tropical Nature, and Other EssaysMacmillan and Company, 1878 - 356 pages |
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Page 88
... selection . the successive variations by which the eyes were reduced and ultimately lost must all have been useful . It is true they do manage to exist without eyes ; but that is probably because , as sight became more and more imper ...
... selection . the successive variations by which the eyes were reduced and ultimately lost must all have been useful . It is true they do manage to exist without eyes ; but that is probably because , as sight became more and more imper ...
Page 123
... selection were always able to keep the teeming mass of organisms in nicely balanced harmony with the changing physical conditions . The equatorial zone , in short , exhibits to us the result of a comparatively con- tinuous and unchecked ...
... selection were always able to keep the teeming mass of organisms in nicely balanced harmony with the changing physical conditions . The equatorial zone , in short , exhibits to us the result of a comparatively con- tinuous and unchecked ...
Page 124
... Selection - The relations and affinities of Humming - birds - How to determine doubtful affinities - Resemblances of Swifts and Humming - birds - Differences between Sun - birds and Humming - birds - Conclusion . THERE are now about ten ...
... Selection - The relations and affinities of Humming - birds - How to determine doubtful affinities - Resemblances of Swifts and Humming - birds - Differences between Sun - birds and Humming - birds - Conclusion . THERE are now about ten ...
Page 140
... Selection . The three species which inhabit Juan Fernandez and Mas - afuera present certain peculiarities of great interest . They form a distinct genus , Eustephanus , one species of which inhabits Chili as well as the island of Juan ...
... Selection . The three species which inhabit Juan Fernandez and Mas - afuera present certain peculiarities of great interest . They form a distinct genus , Eustephanus , one species of which inhabits Chili as well as the island of Juan ...
Page 141
... selection , it will be instructive to see if we can picture to ourselves the process by which the changes have been brought about . We must first go back to an unknown but rather remote period , just before any humming - birds had ...
... selection , it will be instructive to see if we can picture to ourselves the process by which the changes have been brought about . We must first go back to an unknown but rather remote period , just before any humming - birds had ...
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Common terms and phrases
abundant adapted adorned Africa allied Amazon animals ants Asia attract bamboo Batavia beautiful become birds blue brilliant butterflies carnivora causes changes character characteristic climate colour Colours of Animals comparatively conspicuous continent curious Danaidæ Darwin distinct Eocene equator equatorial zone existence extensive fact families fauna favourable feet female ferns fertilization flowers foliage forests fruits genera genus greater green groups habits heat humming-birds hyænas immense inhabit insects Juan Fernandez land larger larvæ leaves lemurs less light Madagascar Malay Archipelago male mammalia marsupials Miocene monkeys natural selection naturalists North northern observed occur ocean ornaments Palearctic parrots peculiar perhaps phenomena plants plumage probably produced proportion protection rays region remarkable resemble sexual selection showy slender sometimes South America species spots structure sun-birds surface tail temperate zones temperature theory tints tion trees tropical trunks Ungulata variation varied variety vegetation whole wings yellow