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Alfred russel wallace wiki
Alfred russel wallace wiki





alfred russel wallace wiki

Haughton enlarges considerably but his chief arguments are reduced to the setting-up of "three unwarrantable assumptions," which he imputes to the Lamarckians and Darwinians, and then, to use his own words, "brings to the ground like a child's house of cards." The first of these is " the indefinite variation of species continuously in the one direction." Now this is certainly never assumed by Mr. On the question of the "origin of species" Mr.I think I have fairly heard and fairly weighed the evidence on both sides, and I remain an utter disbeliever in almost all that you consider the most sacred truths I can see much to admire in all religions But whether there be a God and whatever be His nature whether we have an immortal soul or not, or whatever may be our state after death, I can have no fear of having to suffer for the study of nature and the search for truth."On the Tendency of Varieties to Depart Indefinitely From the Original Type" (1858).This progression, by minute steps, in various directions, but always checked and balanced by the necessary conditions, subject to which alone existence can be preserved, may, it is believed, be followed out so as to agree with all the phenomena presented by organized beings, their extinction and succession in past ages, and all the extraordinary modifications of form, instinct, and habits which they exhibit. We believe we have now shown that there is a tendency in nature to the continued progression of certain classes of varieties further and further from the original type - a progression to which there appears no reason to assign any definite limits - and that the same principle which produces this result in a state of nature will also explain why domestic varieties have a tendency to revert to the original type. Neither did the giraffe acquire its long neck by desiring to reach the foliage of the more lofty shrubs, and constantly stretching its neck for the purpose, but because any varieties which occurred among its antitypes with a longer neck than usual at once secured a fresh range of pasture over the same ground as their shorter-necked companions, and on the first scarcity of food were thereby enabled to outlive them. The powerful retractile talons of the falcon- and the cat-tribes have not been produced or increased by the volition of those animals but among the different varieties which occurred in the earlier and less highly organized forms of these groups, those always survived longest which had the greatest facilities for seizing their prey.Letter to Sir William Jackson Hooker, (1856 or earlier).If I had to fix on two only as representing the perfection of the two classes, I should certainly choose the Durian and the Orange as the king and queen of fruits. It would perhaps not be correct to say that the Durian is the best of all fruits, because it cannot supply the place of subacid juicy fruits such as the orange, grape, mango, and mangosteen, whose refreshing and cooling qualities are so grateful but as producing a food of the most exquisite flavour it is unsurpassed. The smell of the ripe fruit is certainly at first disagreeable, though less so when it has newly fallen from the tree for the moment it is ripe it falls of itself, and the only way to eat Durians in perfection is to get them as they fall."On the Law which has Regulated the Introduction of New Species" (1855).Every species has come into existence coincident both in space and time with a pre-existing closely allied species.







Alfred russel wallace wiki