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Export to Excel select * from OriginOfSpecies where ordinal = '10' order by description desc limit 120, 4 (Page 31: Row)
subject
title
ordinal
description Desending Order (top row is last)
06 - Difficutiles in Theory 06-02 - Transitions 10 As natural selection acts solely by the preservation of profitable modifications, each new form will tend in a fully-stocked country to take the place of, and finally to exterminate, its own less improved parent-form and other less favoured forms with which it comes into competition.
06 - Difficutiles in Theory 06-11 - Organs of Small Importance 10 As natural selection acts by life and death,- by the survival of the fittest, and by the destruction of the less well-fitted individuals,- I have sometimes felt great difficulty in understanding the origin or formation of parts of little importance; almost as great, though of a very different kind, as in the case of the most perfect and complex organs.
13 - Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Or 13-06 - Analogical or adaptive characters 10 As members of distinct classes have often been adapted by successive slight modifications to live under nearly similar circumstances, to inhabit for instance the three elements of land, air, and water, we can perhaps understand how it is that a numerical parallelism has sometimes been observed between the sub-groups in distinct classes.

A naturalist, struck by a parallelism of this nature in any one class, by arbitrarily raising or sinking the value of the groups in other classes (and all our experience shows that this valuation has hitherto been arbitrary), could easily extend the parallelism over a wide range; and thus the septenary, quinary, quaternary, and ternary classifications have probably arisen.

As the modified descendants of dominant species, belonging to the larger genera, tend to inherit the advantages, which made the groups to which they belong large and their parents dominant, they are almost sure to spread widely, and to seize on more and more places in the economy of nature.

The larger and more dominant groups thus tend to go on increasing in size; and they consequently supplant many smaller and feebler groups.

Thus we can account for the fact that all organisms, recent and extinct, are included under a few great orders, under still fewer classes, and all in one great natural system.

As showing how few the higher groups are in number, and how widely spread they are throughout the world, the fact is striking, that the discovery of Australia has not added a single insect belonging to a new order; and that in the vegetable kingdom, as I learn from Dr. Hooker, it has added only two or three orders of small size.

Australia
Australia
04 - Natural Selection 04-02 - Its Power Compared with Man's Selection 10 As man can produce a great result with his domestic animals and plants by adding up in any given direction individual differences, so could natural selection, but far more easily from having incomparably longer time for action.

Nor do I believe that any great physical change, as of climate, or any unusual degree of isolation to check immigration, is necessary in order that new and unoccupied places should be left, for natural selection to fill up by improving some of the varying inhabitants.

For as all the inhabitants of each country are struggling together with nicely balanced forces, extremely slight modifications in the structure or habits of one species would often give it an advantage over others; and still further modifications of the same kind would often still further increase the advantage, as long as the species continued under the same conditions of life and profited by similar
means of subsistence and defence.

No country can be named in which all the native inhabitants are now so perfectly adapted to each other and to the physical conditions under which they live, that none of them could be still better adapted or improved; for in all countries, the natives have been so far conquered by naturalised productions, that they have allowed some foreigners to take firm possession of the land.

And as foreigners have thus in every country beaten some of the natives, we may safely conclude that the natives might have been modified with advantage, so as to have better resisted the intruders.