|
Post by gadreel on Jun 4, 2017 0:14:01 GMT
I absolutely do think that this statement demonstrates a complete lack of knowledge about the theory of natural selection, with the caveat that the way you have presented it is to try to debunk natural selection. Now assuming you have not taken it out of context then, yes the person who said this does not understand natural selection, if however it was intended to say "actually natural selection neither explains nor intends to explain how the 'fittest' got here" then it is a valid point. Perhaps you would enlighten us as to what the point you think the statement has? That woulD be you natural selection isnt even supposeD to explain abiogenesis. Maybe reread what I said, you might find it heavily implied that I agree.
|
|
RedRuth1966
Sophomore
![*](//storage.proboards.com/forum/images/stars/star_yellow.png)
@redruth1966
Posts: 113
Likes: 42
![](http://storage.proboards.com/6692551/images/CTEdkGf0wmfSETIzYiXk.gif)
|
Post by RedRuth1966 on Jun 4, 2017 13:42:34 GMT
Except De Vries himself stated that his theory didn't contradict Darwin's theory of natural selection and he goes on to discuss how other biologists, including Wallace, defined Darwin's views too narrowly. Why don't you quote De Vries himself, surely he knew his own mind better than other biologist's interpretation of what he meant? www.gutenberg.org/files/7234/7234-h/7234-h.htmIt's a fairly pointless argument given that their work underpins current evolutionary theory. Maybe you consider it a pointless argument. I don't consider it pointless because I'm interested in the history of biology. These statements very clearly contradict central claims of Darwin's theory. Or not, if you read and quote what De Vries actually had to say about Darwin, you're trying to second guess De Vries instead of acknowledging what he says or worse still dismiss what he has to say because De Vries's own statements sometimes muddy things a little because he held Darwin in very high regard, and he sometimes claimed to be providing only a minor development of Darwin's theory, rather than a substantial alternative . That's slightly pompous of you. To be fair I don't have much of an interest in the history of Biology beyond my own field but I do know that scientists like to manufacture controversy and cherry pick quotes to suit their argument. Notwithstanding all these apparently unsurmountable difficulties, Darwin discovered the great principle which rules the evolution of organisms. It is the principle of natural selection. It is the sifting out of all organisms of minor worth through the struggle for life. It is only a sieve, and not a force of nature, not a direct cause of improvement, as many of Darwin's adversaries, and unfortunately many of his followers also, have so often asserted.
It is [7] only a sieve, which decides what is to live, and what is to die. But evolutionary lines are of great length, and the evolution of a flower, or of an insectivorous plant is a way with many sidepaths. It is the sieve that keeps evolution on the main line, killing all, or nearly all that try to go in other directions. By this means natural selection is the one directing cause of the broad lines of evolution.
Of course, with the single steps of evolution it has nothing to do. Only after the step has been taken, the sieve acts, eliminating the unfit. The problem, as to the manner in which the individual steps are brought about, is quite another side of the question.
On this point Darwin has recognized two possibilities. One means of change lies in the sudden and spontaneous production of new forms from the old stock. The other method is the gradual accumulation of those always present and ever fluctuating variations which are indicated by the common assertion that no two individuals of a given race are exactly alike. The first changes are what we now call "mutations," the second are designated as "individual variations," or as this term is often used in another sense, as "fluctuations." Darwin recognized both lines of evolution; Wallace disregarded the sudden changes and proposed fluctuations [8] as the exclusive factor. Of late, however, this point of view has been abandoned by many investigators, especially in America. BTW, in one of your posts you say this: ....... First, individual or fluctuating variation, the small variations we find in any population, such as that one person is slightly higher than another, or one group of people have slightly higher average height than another group of people. These variations are due to the action of the environment and do not have a genetic basis. ............... Just as a matter of interest, is that your opinion or what you think De Vries' opinion is/would have been?
|
|
|
Post by 🌵 on Jun 4, 2017 15:35:53 GMT
Maybe you consider it a pointless argument. I don't consider it pointless because I'm interested in the history of biology. These statements very clearly contradict central claims of Darwin's theory. Or not, if you read and quote what De Vries actually had to say about Darwin, you're trying to second guess De Vries instead of acknowledging what he says or worse still dismiss what he has to say because De Vries's own statements sometimes muddy things a little because he held Darwin in very high regard, and he sometimes claimed to be providing only a minor development of Darwin's theory, rather than a substantial alternative . That's slightly pompous of you. To be fair I don't have much of an interest in the history of Biology beyond my own field but I do know that scientists like to manufacture controversy and cherry pick quotes to suit their argument. All I'm doing is expressing the professional consensus. And by "consensus", I mean that probably every historian of evolutionary thought would agree on this. There is no controversy here, manufactured or otherwise. I already have cited three books on the history of biology which confirm the ways in which de Vries's theory contradicted Darwin's. Gould is of course rather controversial at times, but Mayr's book is a very well-respected classic in the history of biology and Peter J. Bowler is one of the foremost historians of evolutionary thought. I can give further references if you want. In the meantime I challenge you to find just one historian of biology who thinks that de Vries's theory does not contradict Darwin's in the ways that I have said. If anybody is trying to manufacture controversy, it's you. I have also given a number of statements from de Vries himself that clearly contradict Darwin. These statements were not throwaway comments; most of them occur in important parts of the works and express the central commitments of his theory. The fact that de Vries sometimes downplayed the differences between his theory and Darwin's, as in the quote you provide, does not mean that those differences weren't there. At the end of the day, if you insist on holding that de Vries's theory was compatible with Darwin's, you need to hold one of two propositions: (1) Darwin was a saltationist or (2) de Vries was not a saltationist. You don't seem to be asserting (2). Is it that you think Darwin was a saltationist?
|
|