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 |
Dentro del libro
Página 50
... become in any degree permanent , necessarily have to struggle with the other inhabitants of the country , the species which are already dominant will be the most likely to yield offspring , which , though in some slight degree modi ...
... become in any degree permanent , necessarily have to struggle with the other inhabitants of the country , the species which are already dominant will be the most likely to yield offspring , which , though in some slight degree modi ...
Página 55
... become converted into new and distinct species . The larger genera thus tend to become larger ; and throughout nature the forms of life which are now dominant tend to become still more dominant by leaving many modified and dominant ...
... become converted into new and distinct species . The larger genera thus tend to become larger ; and throughout nature the forms of life which are now dominant tend to become still more dominant by leaving many modified and dominant ...
Página 60
... become common throughout whole islands in a period of less than ten years . Several of the plants , such as the cardoon and a tall thistle , now most numerous over the wide plains of La Plata , clothing square leagues of surface almost ...
... become common throughout whole islands in a period of less than ten years . Several of the plants , such as the cardoon and a tall thistle , now most numerous over the wide plains of La Plata , clothing square leagues of surface almost ...
Página 67
... become feral , and this would certainly greatly alter ( as indeed I have observed in parts of South America ) the vegetation : this again would largely affect the insects ; and this , as we just have seen in Staffordshire , the ...
... become feral , and this would certainly greatly alter ( as indeed I have observed in parts of South America ) the vegetation : this again would largely affect the insects ; and this , as we just have seen in Staffordshire , the ...
Página 68
... become very rare , or wholly disappear . The number of humble - bees in any district depends in a great degree on the number of field - mice , which destroy their combs and nests ; and Mr. H. Newman , who has long attended to the habits ...
... become very rare , or wholly disappear . The number of humble - bees in any district depends in a great degree on the number of field - mice , which destroy their combs and nests ; and Mr. H. Newman , who has long attended to the habits ...
Otras ediciones - Ver todas
On the Origin of Species by Means of Natural Selection: or the Preservation ... Charles Darwin Vista previa limitada - 2023 |
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