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Author Topic:   Natural Limitation to Evolutionary Processes (2/14/05)
Brad McFall
Member (Idle past 5062 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 62 of 299 (186023)
02-16-2005 10:31 PM
Reply to: Message 51 by Faith
02-16-2005 4:51 PM


Re: evolution does not proceed solely by drastic events
I take a slightly more kinematic than dynamic approach of PaulK so I think it is possible that limits on selection can keep evolution "afloat" even if the zero state be approached. This however is only my own idea and I am having a bit of a problem trying to figure out how to join in in this thread plus my own notes on the relevant issue is not immeidately available to me. I found it quite strange that Will Provine would ask Phil Johnson "what are the limits on selection" when he didnt have reason to think there might be any from breeders' knowledge. I have started to imagine such limits given the "interference" macrothermodynamics has been postulated to hierarchically inlay between boundary conditions Salthe elsewhere philosophized on. The issue I might assist however is on drift as there seems to be a real difference of opinion between Wright and Fisher AND Mayr on that. That is not possible.

This message is a reply to:
 Message 51 by Faith, posted 02-16-2005 4:51 PM Faith has not replied

Brad McFall
Member (Idle past 5062 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 151 of 299 (341137)
08-18-2006 4:11 PM
Reply to: Message 149 by Equinox
08-18-2006 3:25 PM


Re: Considering rapid rate of mutation
Let’s say Faith intended “genetic” in the sense of Bateson as cited by Gould(orange below):
quote:
SJ GOULD "The Structure of Evolutionary Theory"
If she even unconsciously and materially had had a vibrationally envisoned reality of the transient transition from any genetic realism to a form phenotypically ontogenized then she could have used “variation” polyvocally without confounding it with the shape of any particular actual creature. She would have not provided the statistical evidence that such was the case but that it might be collected can not judged against a priori seems to me. Now if a responder to Faith insisted that Bateson was materially incorrect and by analogy of any dream Faith is 'incorrect' as Gould proposed etc., this would not work either, because for Gould to retain his position he needed to deny to D’Arcy Thompson direct imposition whether by a law of nature or the “hand” of God in the Cartesian place of transformed co-ordinates.
As long as there are to be provable limits to natural selection caused change by human artificial selection experiments (Provine denied these exist to Johnson but can one deny these to Faith?) it seems possible that evolution could slow down a posterori (although we do not know this as of yet) if Fisher’s theorem relating genetical variance to fitness was mediated by counter active niche construction (for as Kant said, the first condition he judged would be the habitat not the kind) (counter active construction works organically against already existing selection pressures (see book “NicheConstruction””) mediated by the 2nd law of thermo within macrothermodyanmics(Gladyshev). Thus Fisher’s thought that entropy and his law were analogous would cash out the academic tension supposed to result in nothing between Wright and Fisher into this "genetic variance" that is molecular, no matter what “phase” the history of this biology is incurred to.
Who is to say whether space or time is being represented here??? I think Gould went too far in relating Bateson and Galton but that is just my tail end of the argument. I think rather he failed so “save” the notion of meristic variation itself.

This message is a reply to:
 Message 149 by Equinox, posted 08-18-2006 3:25 PM Equinox has not replied

Replies to this message:
 Message 153 by Faith, posted 08-19-2006 2:17 AM Brad McFall has replied

Brad McFall
Member (Idle past 5062 days)
Posts: 3428
From: Ithaca,NY, USA
Joined: 12-20-2001


Message 160 of 299 (341325)
08-19-2006 8:49 AM
Reply to: Message 153 by Faith
08-19-2006 2:17 AM


Re: Back to reduced genetic variability in speciation events
Yes I was generally supporting you position.
Chicken breeders who have been artifically selecting for more eggs have gotten chickens with better ability to lay more and more eggs.
Will Provine, who grew up on such a farm, and talks with the chickens' dept. at Cornell asserted to Phil Johnson in the mid 90s that there is no limit to this process because the chicks hatched continue to be more fecund. The only graph of this data I saw from Lerner in the 50s indicates that allthough there does appear to be continued improvement in egg productivity the gains made selectively per generation seem to be dropping off.
I think there IS some limit. I have thought up some theoretical means to this end. That is why I do not understand how posters can be objecting to your use of this idea unless like Will they wil it not to be the case but I did not read them asking you for information about the limit itself.

This message is a reply to:
 Message 153 by Faith, posted 08-19-2006 2:17 AM Faith has not replied

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