On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for Life |
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Page 10
... occasional means - Dispersal during the Glacial period co - extensive with the world .. 300 CHAPTER XII GEOGRAPHICAL DISTRIBUTION - continued Distribution of fresh - water productions - On the inhabitants of oceanic islands - Absence of ...
... occasional means - Dispersal during the Glacial period co - extensive with the world .. 300 CHAPTER XII GEOGRAPHICAL DISTRIBUTION - continued Distribution of fresh - water productions - On the inhabitants of oceanic islands - Absence of ...
Page 25
... occasionally revert in some of their characters to ancestral forms , it seems to me not improbable , that if we could succeed in naturalising , or were to cultivate , during many generations , the several races , for instance , of the ...
... occasionally revert in some of their characters to ancestral forms , it seems to me not improbable , that if we could succeed in naturalising , or were to cultivate , during many generations , the several races , for instance , of the ...
Page 29
... occasional crosses , if aided by the careful selection of those individual mongrels which present any desired character ; but that a race could be obtained nearly intermediate between two extremely different races or species , I can ...
... occasional crosses , if aided by the careful selection of those individual mongrels which present any desired character ; but that a race could be obtained nearly intermediate between two extremely different races or species , I can ...
Page 35
... occasionally appearing in all the breeds , both when kept pure and when crossed ; the mongrel offspring being perfectly fertile ; -from these several reasons , taken together , we may safely conclude that all our domestic breeds have ...
... occasionally appearing in all the breeds , both when kept pure and when crossed ; the mongrel offspring being perfectly fertile ; -from these several reasons , taken together , we may safely conclude that all our domestic breeds have ...
Page 42
... occasional preservation of the best indi- viduals , whether or not sufficiently distinct to be ranked at their first appearance as distinct varieties , and whether or not two or more species or races have become blended together by ...
... occasional preservation of the best indi- viduals , whether or not sufficiently distinct to be ranked at their first appearance as distinct varieties , and whether or not two or more species or races have become blended together by ...
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Common terms and phrases
accumulated adapted affinities allied species America analogous ancient animals appear archipelago become bees believe birds breeds cause cells characters cirripedes climate closely allied colour continuous crossed crustaceans degree difficulty distinct species divergence domestic doubt embryo endemic existing exterminated extinct extremely facts favourable fertilised fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hybrids hybrids produced important increase individuals inhabitants inherited insects instance instincts intercrossing intermediate larvæ laws less living males mammals manner migration modification modified descendants natural selection naturalists nearly nest occasionally offspring organic organisation origin of species perfect pigeons plants pollen present principle probably produced progenitor ranked reciprocal crosses remarked resemble rock-pigeon rudimentary seeds sexual sexual selection Silurian slight sometimes South America sterility structure struggle successive supposed swimbladder tend theory variability variations varieties vary whole widely