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133 rows, page 14 of 34 (4/p)
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Export to Excel select * from OriginOfSpecies where ordinal = '10' order by description desc limit 52, 4 (Page 14: Row)
subject
title
ordinal
description Desending Order (top row is last)
13 - Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Or 13-02 - Natural system 10 Naturalists try to arrange the species, genera, and families in each class, on what is called the Natural System.

But what is meant by this system?

Some authors look at it merely as a scheme for arranging together those living objects which are most alike, and for separating those which are most unlike; or as an artificial means for enunciating, as briefly as possible, general propositions, that is, by one sentence to give the characters common, for instance, to all mammals, by another those common to all carnivora, by another those common to the dog-genus, and then by adding a single sentence, a full description is given of each kind of dog.

dog
dog


The ingenuity and utility of this system are indisputable.

But many naturalists think that something more is meant by the Natural System; they believe that it reveals the plan of the Creator; but unless it be specified whether order in time or space, or what else is meant by the plan of the Creator, it seems to me that nothing is thus added to our knowledge.

Such expressions as that famous one of Linnaeus, and which we often meet with in a more or less concealed form, that the characters do not make the genus, but that the genus gives the characters, seem to imply that something more is included in our classification, than mere resemblance.

Carl Linnaeus
Carl Linnaeus


I believe that something more is included; and that propinquity of descent, the only known cause of the similarity of organic beings, is the bond, hidden as it is by various degrees of modification, which is partially revealed to us by our classifications.
04 - Natural Selection 04-12 - On the Degree to which Organisation tends to advance 10 Natural Selection acts exclusively by the preservation and accumulation of variations, which are beneficial under the organic and inorganic conditions to which each creature is exposed at all periods of life.

The ultimate result is that each creature tends to become more and more improved in relation to its conditions.

This improvement inevitable leads to the gradual advancement of the organisation of the greater number of living beings throughout the world.

But here we enter on a very intricate subject, for naturalists have not defined to each other's satisfaction what is meant by an advance in organisation.
04 - Natural Selection 04-13 - Convergence of Character 10 Mr. H. C. Watson thinks that I have overrated the importance of divergence of character (in which, however, he apparently believes) and that convergence, as it may be called, has likewise played a part. If two species, belonging to two distinct though allied genera, had both produced a large number of new and divergent forms, it is conceivable that these might approach each other so closely that they would have all to be classed under the same genus; and thus the descendants of two distinct genera would converge into one.
13 - Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Or 13-07 - Affinities, general, complex and radiating 10 Mr. Waterhouse has remarked that, when a member belonging to one group of animals exhibits an affinity to a quite distinct group, this affinity in most cases is general and not special: thus, according to Mr. Waterhouse, of all Rodents, the bizcacha is most nearly related to Marsupials; but in the points in which it approaches this order, its relations are general, and not to any one marsupial species more than to another.

rodent
rodent

bizcacha
bizcacha

marsupials
marsupials


As the points of affinity of the bizcacha to Marsupials are believed to be real and not merely adaptive, they are due on my theory to inheritance in common.

Therefore we must suppose either that all Rodents, including the bizcacha, branched off from some very ancient Marsupial, which will have had a character in some degree intermediate with respect to all existing Marsupials; or that both Rodents and Marsupials branched off from a common progenitor, and that both groups have since undergone much modification in divergent directions.

On either view we may suppose that the bizcacha has retained, by inheritance, more of the character of its ancient progenitor than have other Rodents; and therefore it will not be specially related to any one existing Marsupial, but indirectly to all or nearly all Marsupials, from having partially retained the character of their common progenitor, or of an early member of the group.

On the other hand, of all Marsupials, as Mr. Waterhouse has remarked, the phascolomys resembles most nearly, not any one species, but the general order of Rodents.

In this case, however, it may be strongly suspected that the resemblance is only analogical, owing to the phascolomys having become adapted to habits like those of a Rodent.