On the Origin of Species by Means of Natural Selection: Or The Preservation of Favoured Races in the Struggle for LifeHumphrey Milford, Oxford University Press, 1923 - 454 páginas |
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... VARIATION UNDER DOMESTICATION 2. VARIATION UNDER NATURE . ✓ 3. STRUGGLE FOR EXISTENCE 4. NATURAL SELECTION 5. LAWS OF VARIATION PAGE 1 7 7 41 56 73 119 6. DIFFICULTIES ON THEORY 154 7. INSTINCT 186 8. HYBRIDISM 220 9. ON THE ...
... VARIATION UNDER DOMESTICATION 2. VARIATION UNDER NATURE . ✓ 3. STRUGGLE FOR EXISTENCE 4. NATURAL SELECTION 5. LAWS OF VARIATION PAGE 1 7 7 41 56 73 119 6. DIFFICULTIES ON THEORY 154 7. INSTINCT 186 8. HYBRIDISM 220 9. ON THE ...
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... variation under domestication , afforded the best and safest clue . I may venture to express my conviction of the high ... variations . I will then pass on to the variability of species in a state of nature ; but I shall , unfortunately ...
... variation under domestication , afforded the best and safest clue . I may venture to express my conviction of the high ... variations . I will then pass on to the variability of species in a state of nature ; but I shall , unfortunately ...
Página 7
... VARIATION UNDER DOMESTICATION Causes of Variability - Effects of Habit - Correlation of Growth- Inheritance ... variation ; and that when the organisation has once begun to vary , it generally continues to vary for many generations . No ...
... VARIATION UNDER DOMESTICATION Causes of Variability - Effects of Habit - Correlation of Growth- Inheritance ... variation ; and that when the organisation has once begun to vary , it generally continues to vary for many generations . No ...
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... variations . But I am strongly inclined to suspect that the most frequent cause of variability may be attributed to the male and female reproductive elements having been affected prior to the act of con- ception . Several reasons make ...
... variations . But I am strongly inclined to suspect that the most frequent cause of variability may be attributed to the male and female reproductive elements having been affected prior to the act of con- ception . Several reasons make ...
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... variation is not necessarily connected , as some authors have sup- posed , with the act of generation . Seedlings from the same fruit , and the young of the same litter , sometimes differ considerably from each other , though both the ...
... variation is not necessarily connected , as some authors have sup- posed , with the act of generation . Seedlings from the same fruit , and the young of the same litter , sometimes differ considerably from each other , though both the ...
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Términos y frases comunes
accumulated adapted affinities allied species America amount analogous ancient appear Archipelago become bees believe birds breeds cause cells characters cirripedes climate closely allied colour common parent continuous crossed crustaceans degree difficulty distinct species divergence doubt embryo endemic Europe existing exterminated extinct extremely facts favourable fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hermaphrodites hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing land larvæ less living male mammals manner Marsupials migration modification modified descendants natural selection naturalists nearly nest oceanic islands offspring organisation perfect pigeons pistil plants pollen present principle probably produced progenitor ranked reciprocal crosses remarked resemble rock-pigeon rudimentary organs seeds sexual selection Silurian slight South America sterility structure struggle successive suppose swimbladder tend theory tion trees variability variation vary whole widely