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133 rows, page 27 of 34 (4/p)
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Export to Excel select * from OriginOfSpecies where ordinal = '10' order by subject desc limit 104, 4 (Page 27: Row)
subject Desending Order (top row is last)
title
ordinal
description
03 - Struggle for Existence 03-10 - Struggle for Life most severe between Individuals and Varieties of the same Species 10 As the species of the same genus usually have, though by no means invariably, much similarity in habits and constitution, and always in structure, the struggle will generally be more severe between them, if they come into competition with each other, than between the species of distinct genera.

We see this in the recent extension over parts of the United States of one species of swallow having caused the decrease of another species.

United States
United States

swallow
swallow


The recent increase of the missel-thrush in parts of Scotland has caused the decrease of the song-thrush.

Scotland
Scotland

Missel Thrush
Missel Thrush

Song Thrush
Song Thrush
03 - Struggle for Existence 03-11 - The Relation of Organism to Organism the Most Important of All Relations 10 A corollary of the highest importance may be deduced from the foregoing remarks, namely, that the structure of every organic being is related, in the most essential yet often hidden manner, to that of all the other organic beings, with which it comes into competition for food or residence, or from which it has to escape, or on which it preys.

This is obvious in the structure of the teeth and talons of the tiger; and in that of the legs and claws of the parasite which clings to the hair on the tiger's body.

talon
talon

tiger
tiger

Head Louse Claw
Head Louse Claw


But in the beautifully plumed seed of the dandelion, and in the flattened and fringed legs of the water-beetle, the relation seems at first confined to the elements of air and
water.

dandelion
dandelion

flying seeds
flying seeds

Water Beetle
Water Beetle


Yet the advantage of plumed seeds no doubt stands in the closest relation to the land being already thickly clothed with other plants; so that the seeds may be widely distributed and fall on unoccupied ground.

In the water-beetle, the structure of its legs, so well adapted for diving, allows it to compete with other aquatic insects, to hunt for its own prey, and to escape serving as prey to other animals.
03 - Struggle for Existence 03-12 - Summary 10 It is good thus to try in imagination to give to any one species an advantage over another.

Probably in no single instance should we know what to do.

This ought to convince us of our ignorance on the mutual relations of all organic beings; a conviction as necessary as it is difficult to acquire.
03 - Struggle for Existence 03-06 - Competition Universal 10 Eggs or very young animals seem generally to suffer most, but this is not invariably the case. With plants there is a vast destruction of seeds, but, from some observations which I have made, it appears that the seedlings suffer most from germinating in ground already thickly stocked with other plants.

Seedlings, also, are destroyed in vast numbers by various enemies; for instance, on a piece of ground three feet long and two wide, dug and cleared, and where there could be no choking from other plants, I marked all the seedlings of our native weeds as they came up, and out of 357 no less than 295 were destroyed, chiefly by slugs and insects.

seedling
seedling

slug
slug

insect
insect


If turf which has long been mown, and the case would be the same with turf closely browsed by quadrupeds, be let to grow, the more vigorous plants gradually kill the less vigorous, though fully grown plants; thus out of twenty species growing on a little plot of mown turf (three feet by four) nine species perished, from the other species being allowed to grow up freely.

quadruped
quadruped

zebra
zebra