tag:blogger.com,1999:blog-3855268335402896473.post2341663556465908216..comments2024-01-23T02:32:28.567-08:00Comments on Darwin's God: A Member of the National Academy of Sciences Repeated This Huge Evolution BlunderUnknownnoreply@blogger.comBlogger81125tag:blogger.com,1999:blog-3855268335402896473.post-59323229254754018042012-06-17T15:31:08.888-07:002012-06-17T15:31:08.888-07:00velikovskys,
"a change in predator or condit...velikovskys,<br /><br />"a change in predator or conditions wipe out the entire crop The more diverse a population the larger chance some in the population will fit into the new conditions"<br /><br />A change in conditions can wipe out a whole population in some cases, but as I said, it is not inevitable.Nichttps://www.blogger.com/profile/08693133888203943510noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-91006846440635263432012-06-15T10:41:37.243-07:002012-06-15T10:41:37.243-07:00It's totally untrue that a change in environme...<i>It's totally untrue that a change in environment leads inevitably to the demise of a species unless it possesses a mutation which would give it an advantage.</i><br /><br />Yes, of course it's untrue. Nobody has claimed that.<br /><br />But rapid enviromental change certainly puts populations at risk of extinction, as adaptation takes time.<br /><br />And does not depend on "a mutation", but on sampling of those genetic variants that tend to promote reproductive success in the changed environment.Elizabeth Liddlehttps://www.blogger.com/profile/02465414316063910821noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-82064596875709907902012-06-15T07:03:16.219-07:002012-06-15T07:03:16.219-07:00Tell that to all the mega fauna which occupied Nor...Tell that to all the mega fauna which occupied North America before the arrival of man. There is the same problem with crops bred for certain yields, a change in predator or conditions wipe out the entire crop The more diverse a population the larger chance some in the population will fit into the new conditionsvelikovskyshttps://www.blogger.com/profile/10957523527184649923noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-33848890138052419362012-06-13T13:07:14.348-07:002012-06-13T13:07:14.348-07:00velikovskys
"Too narrow fitness, change in e...velikovskys<br /><br />"Too narrow fitness, change in environment,adios"<br /><br />There is no better way to put this, rubbish!<br />Animals will often adapt to a change in environment. It's totally untrue that a change in environment leads inevitably to the demise of a species unless it possesses a mutation which would give it an advantage.Nichttps://www.blogger.com/profile/08693133888203943510noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-13048421772944416142012-06-13T09:08:55.148-07:002012-06-13T09:08:55.148-07:00So it's kind of like a Goldilocks thing. Fitne...<i>So it's kind of like a Goldilocks thing. Fitness requirements not too tight, not too loose. </i><br /><br />Well, it depends what outcome you are interested in, but in a sense, yes, at least if you are looking for complex and/or ingenious "solutions" to the problem of thriving in a challenging environment.<br /><br />A very harsh environment may limit adaptation because "solutions" along pathways that require deleterious intermediates may be unavailable. On the other hand a very forgiving environment may not do enough filtering to allow for interesting accumulations of advantageous genetic variants.<br /><br /><i>How does that work in real life?</i><br /><br />Some very harsh environments only support a very limited range of lifeforms (extremophile bacteria, for instance); some populations go extinct when a benign environment is followed by a harsher one, because what was not deleterious in the benign environment becomes highly deleterious in the harsh environment; some populations are over-specialised and go extinct when their habitat is destroyed.Elizabeth Liddlehttps://www.blogger.com/profile/02465414316063910821noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-58805889668067169022012-06-12T06:21:49.128-07:002012-06-12T06:21:49.128-07:00oleg said
"It's a historical quirk, Blas....oleg said<br />"It's a historical quirk, Blas." <br /><br />Behind any long lasting quirk there is a reason.<br /><br />"(An then there is the fact that random is an adjective, so random drift could not turn into random.)"<br /><br />But you can use ramdomly. <br /><br />"But be that as it may, Blas, you are asking the wrong question. To see what I mean, watch Richard Feynman's explanation on the difference between knowing the name of something and knowing something."<br /><br /><br />I know the difference, but I do not underestimate the power of naming.Blashttps://www.blogger.com/profile/13205610477389739651noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-81276062073709334102012-06-12T06:13:05.941-07:002012-06-12T06:13:05.941-07:00It's a historical quirk, Blas. (An then there ...It's a historical quirk, Blas. (An then there is the fact that <i>random</i> is an adjective, so <i>random drift</i> could not turn into <i>random</i>.) <br /><br />But be that as it may, Blas, you are asking the wrong question. To see what I mean, watch <a href="http://www.youtube.com/watch?v=05WS0WN7zMQ" rel="nofollow">Richard Feynman's explanation</a> on the difference between knowing the name of something and knowing something.oleghttps://www.blogger.com/profile/11644793385433232819noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-42525157351217492112012-06-12T05:57:35.959-07:002012-06-12T05:57:35.959-07:00Thanks again Oleg. But now I am more confused as t...Thanks again Oleg. But now I am more confused as there was two concepts "steady drift" and "ramdom drift". So why "ramdom drift" became "drift" instead of "ramdom"?Blashttps://www.blogger.com/profile/13205610477389739651noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-76634401708068158692012-06-12T05:49:34.492-07:002012-06-12T05:49:34.492-07:00Genetic drift: History of the concept.<a href="http://en.wikipedia.org/wiki/Genetic_drift#History_of_the_concept" rel="nofollow">Genetic drift: History of the concept</a>.oleghttps://www.blogger.com/profile/11644793385433232819noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-39692451323438669552012-06-12T05:40:08.166-07:002012-06-12T05:40:08.166-07:00Thanks Oleg, but that wasn`t my question. I would ...Thanks Oleg, but that wasn`t my question. I would like to know why biologists uses the word "drift" instead "ramdom".Blashttps://www.blogger.com/profile/13205610477389739651noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-8063505954880689052012-06-12T05:36:24.251-07:002012-06-12T05:36:24.251-07:00Wikipedia has a good entry: Genetic drift.Wikipedia has a good entry: <a href="http://en.wikipedia.org/wiki/Genetic_drift" rel="nofollow">Genetic drift</a>.oleghttps://www.blogger.com/profile/11644793385433232819noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-11322190718612117782012-06-12T04:55:02.002-07:002012-06-12T04:55:02.002-07:00"It's called neutral drift. We can have n..."It's called neutral drift. We can have neutral mutation A occur any time in the past and be fixed through drift,"<br /><br /><br />May a darwinist of this forum explain why is used the word "drift" instead of chance? <br />As I understand "drift" is used to explain that a given alele became predominant because it happen ramdomly in any binomial distribution.Blashttps://www.blogger.com/profile/13205610477389739651noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-56951217939033994412012-06-11T21:46:49.112-07:002012-06-11T21:46:49.112-07:00oleg:
Hunter: It would require a long series of r...oleg:<br /><br /><i>Hunter: It would require a long series of random mutations that just happens to construct an incredible biological design. <br /><br />oleg: I share Elizabeths amazement at how someone with a biophysics background can have this sort of basic misunderstanding.</i><br /><br />It is unclear where you have discovered the misunderstanding. Is the series not long, the biological variation not random, or the biological designs not complex?<br /><br /><br /><i>Are you equally amazed that genetic algorithms are able to find solutions to difficult problems even though they are likewise based on random mutations? Or that Monte Carlo algorithms can optimize pretty well?</i><br /><br />No I am not.<br /><br /><br /><i>Such childish behavior would be excusable for a layman but not for someone with a PhD in biophysics from a respectable university.</i><br /><br />You are the one equating GA’s and MC’s with the evolution of consciousness.Cornelius Hunterhttps://www.blogger.com/profile/12283098537456505707noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-55577692427026327772012-06-11T19:41:08.335-07:002012-06-11T19:41:08.335-07:00Too narrow fitness, change in environment,adiosToo narrow fitness, change in environment,adiosvelikovskyshttps://www.blogger.com/profile/10957523527184649923noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-75633366727114418852012-06-11T18:42:24.663-07:002012-06-11T18:42:24.663-07:00But its fitness that drives evolution. Unless ther...But its fitness that drives evolution. Unless there is too much fitness.natschusterhttps://www.blogger.com/profile/13127240463824366637noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-11559300417432789282012-06-11T16:50:43.081-07:002012-06-11T16:50:43.081-07:00natschuster: Fitness requirements not too tight, n...<b>natschuster</b>: <i>Fitness requirements not too tight, not too loose. How does that work in real life?</i><br /><br />The world is a big place. Organisms will spread out and diversify in order to reduce direct competition.Zachrielhttps://www.blogger.com/profile/11268229653808829377noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-25068026157920475022012-06-11T16:14:32.719-07:002012-06-11T16:14:32.719-07:00So it's kind of like a Goldilocks thing. Fitne...So it's kind of like a Goldilocks thing. Fitness requirements not too tight, not too loose. How does that work in real life?natschusterhttps://www.blogger.com/profile/13127240463824366637noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-40727551301116086382012-06-11T14:12:25.773-07:002012-06-11T14:12:25.773-07:00Refutation Of Evolutionary Algorithms
"Darwi...Refutation Of Evolutionary Algorithms<br /><br />"Darwin or Design" with Dr. Tom Woodward with guest Dr. Robert J. Marks II - video<br />http://www.youtube.com/watch?v=Yoj9xo0YsOQbornagain77https://www.blogger.com/profile/16666666037080692370noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-24106504526381433362012-06-11T13:57:18.333-07:002012-06-11T13:57:18.333-07:00I'm not sure what your point is. I'm sayin...<i>I'm not sure what your point is. I'm saying that, to the best of my knowledge computer generated GA are not a very good way to design something like a motor, or a flagellum. Are you agreeing with.</i><br /><br />I'm saying that if you want to design a specific complex piece of equipment, GAs may not scale up.<br /><br />That doesn't mean that evolutionary processes (or GAs) can't produce amazingly complex pieces of equipment, it just means that they may not produce the piece of equipment the GA writer happened to want.<br /><br />A very high-dimensioned GA might deliver a submarine when what you wanted was a washing machine.<br /><br />Or a squid when you wanted a tree.Elizabeth Liddlehttps://www.blogger.com/profile/02465414316063910821noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-29526995598156904782012-06-11T13:48:12.776-07:002012-06-11T13:48:12.776-07:00natschuster: But does a real loose fitness criteri...natschuster: <i>But does a real loose fitness criterion work in real life. Most organisms that aren't fit enough die. How relaxed can you get before it becomes meaningless.</i><br /><br />Well, by definition, an organism that isn't fit enough to live, dies, or isn't fit enough to reproduce, dies without issue.<br /><br />The issue is what proportion of offspring are viable, and as offspring tend to be very like their parents (because inheritance is pretty faithful), and their parents are, by definition, viable, most offspring will be viable.<br /><br />The important thing is that there is plenty of variance, and the ranking isn't too severe (the competition too strong). If only the very fittest survive, the population variance will be reduced, and the population will run the risk of failing to have enough variance to adapt in the face of environmental change. This does, of course, happen, and most populations that have ever existed have gone extinct.<br /><br />However, as long as conditions are tolerable enough that a range of genotypes produce viable phenotypes, then the population stands a good chance of maintaining enough variance to be able to adapt to change.Elizabeth Liddlehttps://www.blogger.com/profile/02465414316063910821noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-18265580789638450692012-06-11T13:07:55.697-07:002012-06-11T13:07:55.697-07:00And here is a happy ending: March 20, 2012 at 3:51...And here is a happy ending: <a href="http://theskepticalzone.com/wp/?p=576&cpage=9#comment-8835" rel="nofollow">March 20, 2012 at 3:51 pm</a><br /><br />A genetic algorithm generates 500 bits of specified information.oleghttps://www.blogger.com/profile/11644793385433232819noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-1873433877649041942012-06-11T13:00:01.004-07:002012-06-11T13:00:01.004-07:00Technically speaking, all organisms (whether bette...Technically speaking, <i>all</i> organisms (whether better fit or not) die—eventually. The important point is that better fit organisms leave behind more offspring. Sometimes the process is dominated by the nonrandom component (natural selection) and sometimes by the random one (neutral drift). Both limits have been studied in quantitative models and in a biological setting.oleghttps://www.blogger.com/profile/11644793385433232819noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-26572803403329818272012-06-11T12:56:35.099-07:002012-06-11T12:56:35.099-07:00This is the thread: Creating CSI with NS.
The rel...This is the thread: <a href="http://theskepticalzone.com/wp/?p=576" rel="nofollow">Creating CSI with NS</a>. <br />The relevant discussion starts about here: <a href="http://theskepticalzone.com/wp/?p=576&cpage=7#comment-8585" rel="nofollow">March 18, 2012 at 5:20 pm</a>oleghttps://www.blogger.com/profile/11644793385433232819noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-59910064120611376102012-06-11T12:55:06.726-07:002012-06-11T12:55:06.726-07:00But does a real loose fitness criterion work in re...But does a real loose fitness criterion work in real life. Most organisms that aren't fit enough die. How relaxed can you get before it becomes meaningless.natschusterhttps://www.blogger.com/profile/13127240463824366637noreply@blogger.comtag:blogger.com,1999:blog-3855268335402896473.post-81604244005199310952012-06-11T12:44:50.963-07:002012-06-11T12:44:50.963-07:00natschuster: Does neutral drift work in computer g...natschuster: <i>Does neutral drift work in computer generated GA's? And what about case where the mutations involved are actually harmful unless they happen all at once, e.g. a protein gaining a new ability but losing stability unless there is are compensating mutations.</i> <br /><br />A while ago Elizabeth blogged about her experience with a numerical simulation of this sort. She can point you to the exact thread on her blog for details, but the bottom line was that a greedy algorithm had a hard time finding the best solutions as it tended to get stuck at local optima. A more relaxed selection preserved genomes that went down in the fitness landscape but eventually got to even higher fitness. So, yeah, neutral drift exists in GAs and is quite helpful in optimization.oleghttps://www.blogger.com/profile/11644793385433232819noreply@blogger.com