Online reading group and book discussion forum
  HOME FORUMS BOOKS LINKS DONATE ADVERTISE CONTACT  
View unanswered posts | View active topics It is currently Sat Aug 02, 2014 3:36 am




Post new topic Reply to topic  [ 11 posts ] • Topic evaluate: Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average. 
Universal Symbiosis 
Author Message


Post Universal Symbiosis
Quote:
...Being a colony of colonies of colonies seems to be a successful recipe for life.

I want to return to the genes' eye view and push the idea of universal symbiosis--'living together'--to its ultimate conclusion. Margulis is rightly seen as a high priestess of symbiosis. As I said earlier, I would go even further, and regard all 'normal' nuclear genes as symbiotic in the same kind of way as mitochondrial genes. But where Margulis and Lovelock invoke the poetry of cooperation and amity as the primary in the union, I want to do the opposite and regard it as a secondary consequence. At the genetic level all is selfish, but the selfish ends of genes are served by cooperation at many levels.



From the chapter: The Selfish Cooperator, p 231.

Judging from this it would seem that Dawkins holds the belief that evolution is directional and 'progresses' (indirectly) toward the tendency of collaboration. And not only that, but there seems to be an implicit affirmation of the idea of increasing complexity especially in terms of colonial approbation and integration.

I know that in the past, there has been some disagreement amongst ourselves as to whether or not there is a direction of evolution and whether or not the idea of increasing complexity is sound. Am I interpreting Dawkin's correctly on these matters and if so, what do you all think about.




Mon May 19, 2003 1:04 pm
Years of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membership
Intelligent

Bronze Contributor 2

Joined: Oct 2002
Posts: 554
Location: Saint Louis
Thanks: 0
Thanked: 0 time in 0 post
Gender: Male
Country: United States (us)

Post Re: Progress?
By remarkable luck, Dawkins was good enough to write an entire essay on the topic:
Quote:
To evolution: is it progressive? Gould's definition of progress is a human-chauvinistic one which makes it all too easy to deny progress in evolution. I shall show that if we use a less anthropocentric, more biologically sensible, more 'adaptionist' definition, evolution turns out to be clearly and importantly progressive in the short to medium term. In another sense it is probably progressive in the long term to.

Gould's definition of progress, calculated to deliver a negative answer to the question whether evolution is progressive, is

a tendency of life to increase in anatomical complexity, or neurological elaboration, or size and flexibility of behavioral repertoire, and any criterion obviously concocted (if we would only be honest and introspective enough about our motives) to pace Homo sapiens atop a supposed heap.

My alternative, 'adaptionist' definition of progress is

a tendency for lineages to improve cumulatively their adaptive fit to their particular way of life, by increasing the numbers of features which combine together in adaptive complexes.

. . .

By this definition, adaptive evolution is not just incidentally progressive, it is deeply, dyed-in-the-wool, indispensably progressive. It is fundamentally necessary that it should be progressive if Darwinian natural selection is to perform the explanatory role in our world view that we require of it, and that it alone can perform. Here's why.

Creationists love Sir Fred Hoyle's vivid metaphor for his own misunderstanding of natural selection. It is as if a hurricane, blowing through a junkyard, had the good fortune to assemble a Boeing 747. Hoyle's point is about statistical improbability. Our answer, yours and mine and Stephen Gould's, is that natural selection is cumulative. There is a ratchet, such that small gains are saved. The hurricane doesn't spontaneously assemble the airliner in one go. Small improvements are added bit by bit. To change the metaphor, however daunting the sheer cliffs that the adaptive mountain first presents, graded ramps can be found the other side and the peak eventually scaled. Adaptive evolution must be gradual and cumulative, not because the evidence supports it (though it does) but because nothing except gradual accumulation could, in principle, do the job of solving the 747 riddle. Even divine creation wouldn't help. Quite the contrary, since any entity complicated and intelligent enough to perform the creative role would itself be the ultimate 747. And for exactly the same reason the evolution of complex, many-parted adaptations must be progressive. Later descendants will have accumulated a larger number of components towards the adaptive combination than earlier ancestors.
Richard Dawkins, "Human Chauvinism and Evolutionary Progress"



Mon May 19, 2003 9:00 pm
Profile Email


Post Re: Progress?
What sometimes gets me confused is the misassociation of teleological progress with the immediate and indifferent progress of cumulation Dawkins seems to refer to. When we speak of evolution is terms of progression, the natural but misleading reaction for me is to ask 'progress towards what', as if evolution has some ultimate or teleological ends. Clearly that is a poor way to look at what is a systemmatic and indiscriminative process, but I think it is a mental pitfall that is easily fallen into, especially if ornamented in anthropocentric language.

What is not clear to me, however, is why evolution necessarily progresses toward increasing adaptive complexity. It seems that Dawkins definition applies only to the adaptive complexity of local lineages and not to the average complexity of lineages as a whole. It seems to me that there are instances where the mechanism of evolution could best be served via a reduction of complexity.




Tue May 20, 2003 2:49 pm


Post Re: Progress?
The simple answer to the question of why evolution seems to progress in the direction of increased complexity is that there is nowhere else to go. If you start with a very simple organism, even if the direction of evolution is 100% random, the lineages it engenders will tend on average to be more complex (if they deviate from the original form, they can only go in one direction.) In the case of a more complex form, the "scattering" will occur in both directions: towards more complex systems and possibly also towards simpler systems, if they are adaptive. The simpler forms are nothing to write home about, since they are no more complex than the lineage's ancestors, and are probably comparable to existing forms. The more complex forms, however, are "paving new ground". Normally this sort of scattering would "average out", except that in this case you can't "go below zero" (i.e. there is a certain lower limit to complexity.) Because of this there will be increasing complexity in biological systems. It is not necessary for there to be a consistent adaptive pressure towards more complex forms for these forms to progressively appear, only that they are adaptive some of the time. Even in the situation where simpler forms are more adaptive in 95% of situations, the progression of biological complexity is inevitable.




Tue May 20, 2003 5:31 pm


Post Re: Progress?
What do you think about the argument that biological complexity is impeded by a principle of diminishing returns? What I mean is, suppose a simple organism is sufficiently adapted to a particular set of environments. I'm not a biologist so I'm afraid a lucid example will not be forthcoming. Now suppose that this organism adapts by means of increasing its complexity to excel within a particular subset of its previous environment. In other words, its complexity is translated into specificity allowing it to occupy and dominate a niche-environment. Further development complexity along these lines paints an organism into a specific corner and eventually imposes a 'soft' limit upon its adaptive capacity. It could be argued in response to this argument, that complexity gravitates not only toward the niche category, but also toward the generic. Organisms whose complexity allows them to survive within a range of environments are more equiped to propagate themselves than organisms confined to narrowly defined environments. Yet it would seem that even in this category, the more complex an organism becomes, the more dependent it is (i.e. inflexible) upon its antecedent adaptations and the less responsive it is to increased complexity. What this suggests to me is that while evolution may always be driven toward increasing complexity, that complexity is nebulously bounded, both in terms of generic and specific adaptivity, by a principle of diminishing returns. If this is the case, is it still appropriate to call evolution progressive?

Edited by: Timothy Schoonover at: 5/20/03 6:21:05 pm



Tue May 20, 2003 6:20 pm
Years of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membership
Intelligent

Bronze Contributor 2

Joined: Oct 2002
Posts: 554
Location: Saint Louis
Thanks: 0
Thanked: 0 time in 0 post
Gender: Male
Country: United States (us)

Post Re: Progress?
This is exactly why Dawkins talks about "adaptive fit" instead of complexity. Becoming simpler is actually the norm for parasites; and the bacteria have done remarkably well without much increase in complexity in the last, oh, three billion years or so. Moles who live underground loose their eyes because eyes have a cost with no benefit for them. Parasites that live in another animal loose their integument because it simply gets in the way. Mockingbirds have lost the ability to build nests.

But in each of these cases, you will notice that the change is adaptive. Parasites become less complex because it benefits them; birds' wings have become more complex because it helps them fly better. Each is progress in the adaptive sense without invoking teleology.

I think Louis is right that the "drunkard's walk" gets replicators started on the path to greater complexity, but adaptation keeps us going.




Wed May 21, 2003 4:52 pm
Profile Email


Post Re: Progress?
I'm still kind of struggling with these concepts. Are you saying that by progression Dawkins means a continuous tailoring of the organism towards a relatively greater adaptivity which may or may not involve increased biological complexity? It just seems to me that the more biologically complex an organism is, the less likely an increase in complexity will result in a better adaptive fit. If adaption is the impetus, as complexity increases, wouldn't the impetus gradually decrease and eventually reverse?

Hehe, it's amatuer hour in the forums today. Please bear with me.




Wed May 21, 2003 6:24 pm
User avatar
Years of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membership
Agrees that Reading is Fundamental

Bronze Contributor 2

Joined: Aug 2002
Posts: 287
Location: Fort Collins, CO
Thanks: 0
Thanked: 3 times in 2 posts
Gender: Male

Post Re: Progress?
Complexity isn't beneficial if it doesn't bring about adaptivity. Sometimes you need to lose something to become better able to survive. Look at the tape worm. It's basically a meter or more of skin and ganglia and reproductive organs. No digestive system is needed, because it lives in a hosts intestine, which is full of already-digested material, and it only has to absorb nutrients through it's thin skin. All it really needs to do is reproduce, have its eggs carried out with the hosts feces, and repeat the cycle of parasitism.

There's a plant (can't remember the name, unfortunately), that's adapted to it's environment by becoming more like an ancient plant called chara, which lacks a good deal of "modern" plant systems, but it survives.

Edited by: Jeremy1952 at: 5/22/03 5:51:25 am



Wed May 21, 2003 10:26 pm
Profile YIM WWW
Years of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membership
Intelligent

Bronze Contributor 2

Joined: Oct 2002
Posts: 554
Location: Saint Louis
Thanks: 0
Thanked: 0 time in 0 post
Gender: Male
Country: United States (us)

Post Re: Progress?
Timothy
Quote:
If adaption is the impetus, as complexity increases, wouldn't the impetus gradually decrease and eventually reverse?
What prevents adaptation from coasting to a halt is known as the "Red Queen Effect", or arms races. When you say "environment" my first inclination is to think of the air and water, to which we do become optimally adapted; and adaptations for, say, retrieving oxygen from the water or air are remarkably stable for millions of years. But for an organism or a gene, its environment is mostly made up of other organisms and other genes. When a random mutation in the wildebeest allows it to run a little faster, the environment of lions has changed.

Say the mutation in the wildebeest made the muscle cells in its legs grow a little faster. Wildebeest with this allele run faster and so lions catch their slower brethren, until the herd is predominated by the new version. So far obvious, yes? But what about the environment of red blood cell producing genes in wildebeest? Their environment has changed, too. Before the muscle mutation, a variation in the direction of more blood cells may have been harmful, but now the animal has a use for them; its new muscles need more oxygen, and so higher red blood cell count gets selected.

Lions' "response" is not necessarily greater speed. They could get smarter, to compensate; they could get more cooperative. Or they could go extinct. Or find a different herbivore to eat.

The thing about the red queen is, she never stops. (in Alice in Wonderland, the Red Queen explained a race where everyone had to run as fast as they could, just to stay in the same place). The term has been adopted in biology because predators and prey, parasites and hosts, sexual competitors, and even plant cohorts (trees get tall to compete with other trees) are adapting to each other as fast as they can, just to stay even with the competition.




Thu May 22, 2003 5:50 am
Profile Email


Post Collaboration?
Quote
'As I said earlier, I would go even further, and regard all 'normal' nuclear genes as symbiotic in the same kind of way as mitochondrial genes'
There are some recent papers that suggest that certain evolutionary changes in the genome are due to retrovirus infection (or symbiosis within the nucleus). Apparently there are 8 species of Rock Wallaby in Queensland that differ due to retrovirus action. I couldn't find a direct link, only a reference to this in:
www.comp.nus.edu.sg/~cs62.../02.bw.pdf
It has even been suggested that the nucleus within Eukaryotic cells could have formed initially from a symbiotic virus.

Is this kind of symbiosis considered 'collaboration' or 'selfish infection'? It would certainly lead to increased complexity, as you are effectively adding the genotypes together. I would speculate that this process is more often succesful than any process that tried to reduce the complexity of a genome. If there is no upper limit to genome complexity, then where is the pressure to reduce it? 95%+ of our DNA is so called 'junk' DNA.. remnants of unwanted (viral?) proteins & enzymes. Possibly these are 'stored in case they are ever needed again', but I prefer the explanation that as they are randomly interspersed throughout the genome, it would be extremely difficult to remove the junk without damage, & probably harmful to the animal as it would reduce the rate of genome mixing that occurs during sex. Thus we have selfish gene reasons for increased genetic complexity, that also benefit to collaborate whole.

Question: Is a tapeworm genetically simpler than an earthworm? Or does it have the genes for a digestive system but never expresses them (they're part of the 'junk')?

You can't judge a genome by its organism... :lol




Fri May 23, 2003 10:31 am
Years of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membershipYears of membership
Intelligent

Bronze Contributor 2

Joined: Oct 2002
Posts: 554
Location: Saint Louis
Thanks: 0
Thanked: 0 time in 0 post
Gender: Male
Country: United States (us)

Post Re: Collaboration?
Interesting questions, Dom. Birds have very much less "junk" than the rest of us... the hypothesis is, that weight is so critical to bird survival that there is actually selective pressure against non-coding DNA.




Fri May 23, 2003 2:27 pm
Profile Email
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 11 posts ] • Topic evaluate: Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average.Evaluations: 0, 0.00 on the average. 



Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:


A Nation Under Judgment by Richard Capriola


BookTalk.org Links 
Forum Rules & Tips
Frequently Asked Questions
BBCode Explained
Info for Authors & Publishers
Featured Book Suggestions
Author Interview Transcripts
Be a Book Discussion Leader!
    

Love to talk about books but don't have time for our book discussion forums? For casual book talk join us on Facebook.

Featured Books






BookTalk.org is a free book discussion group or online reading group or book club. We read and talk about both fiction and non-fiction books as a group. We host live author chats where booktalk members can interact with and interview authors. We give away free books to our members in book giveaway contests. Our booktalks are open to everybody who enjoys talking about books. Our book forums include book reviews, author interviews and book resources for readers and book lovers. Discussing books is our passion. We're a literature forum, or reading forum. Register a free book club account today! Suggest nonfiction and fiction books. Authors and publishers are welcome to advertise their books or ask for an author chat or author interview.


Navigation 
MAIN NAVIGATION

HOMEFORUMSBOOKSTRANSCRIPTSOLD FORUMSADVERTISELINKSFAQDONATETERMS OF USEPRIVACY POLICY

BOOK FORUMS FOR ALL BOOKS WE HAVE DISCUSSED
Frankenstein - by Mary ShelleyThe Big Questions - by Simon BlackburnScience Was Born of Christianity - by Stacy TrasancosThe Happiness Hypothesis - by Jonathan HaidtA Game of Thrones - by George R. R. MartinTempesta's Dream - by Vincent LoCocoWhy Nations Fail - by Daron Acemoglu and James RobinsonThe Drowning Girl - Caitlin R. KiernanThe Consolations of the Forest - by Sylvain TessonThe Complete Heretic's Guide to Western Religion: The Mormons - by David FitzgeraldA Portrait of the Artist as a Young Man - by James JoyceThe Divine Comedy - by Dante AlighieriThe Magic of Reality - by Richard DawkinsDubliners - by James JoyceMy Name Is Red - by Orhan PamukThe World Until Yesterday - by Jared DiamondThe Man Who Was Thursday - by by G. K. ChestertonThe Better Angels of Our Nature by Steven PinkerLord Jim by Joseph ConradThe Hobbit by J. R. R. TolkienThe Hitchhiker's Guide to the Galaxy by Douglas AdamsAtlas Shrugged by Ayn RandThinking, Fast and Slow - by Daniel KahnemanThe Righteous Mind - by Jonathan HaidtWorld War Z: An Oral History of the Zombie War by Max BrooksMoby Dick: or, the Whale by Herman MelvilleA Visit from the Goon Squad by Jennifer EganLost Memory of Skin: A Novel by Russell BanksThe Structure of Scientific Revolutions by Thomas S. KuhnHobbes: Leviathan by Thomas HobbesThe House of the Spirits - by Isabel AllendeArguably: Essays by Christopher HitchensThe Falls: A Novel (P.S.) by Joyce Carol OatesChrist in Egypt by D.M. MurdockThe Glass Bead Game: A Novel by Hermann HesseA Devil's Chaplain by Richard DawkinsThe Hero with a Thousand Faces by Joseph CampbellThe Brothers Karamazov by Fyodor DostoyevskyThe Adventures of Huckleberry Finn by Mark TwainThe Moral Landscape by Sam HarrisThe Decameron by Giovanni BoccaccioThe Road by Cormac McCarthyThe Grand Design by Stephen HawkingThe Evolution of God by Robert WrightThe Tin Drum by Gunter GrassGood Omens by Neil GaimanPredictably Irrational by Dan ArielyThe Wind-Up Bird Chronicle: A Novel by Haruki MurakamiALONE: Orphaned on the Ocean by Richard Logan & Tere Duperrault FassbenderDon Quixote by Miguel De CervantesMusicophilia by Oliver SacksDiary of a Madman and Other Stories by Nikolai GogolThe Passion of the Western Mind by Richard TarnasThe Left Hand of Darkness by Ursula K. Le GuinThe Genius of the Beast by Howard BloomAlice's Adventures in Wonderland by Lewis Carroll Empire of Illusion by Chris HedgesThe Sound and the Fury by William Faulkner The Extended Phenotype by Richard DawkinsSmoke and Mirrors by Neil GaimanThe Selfish Gene by Richard DawkinsWhen Good Thinking Goes Bad by Todd C. RinioloHouse of Leaves by Mark Z. DanielewskiAmerican Gods: A Novel by Neil GaimanPrimates and Philosophers by Frans de WaalThe Enormous Room by E.E. CummingsThe Picture of Dorian Gray by Oscar WildeGod Is Not Great: How Religion Poisons Everything by Christopher HitchensThe Name of the Rose by Umberto Eco Dreams From My Father by Barack Obama Paradise Lost by John Milton Bad Money by Kevin PhillipsThe Secret Garden by Frances Hodgson BurnettGodless: How an Evangelical Preacher Became One of America's Leading Atheists by Dan BarkerThe Things They Carried by Tim O'BrienThe Limits of Power by Andrew BacevichLolita by Vladimir NabokovOrlando by Virginia Woolf On Being Certain by Robert A. Burton50 reasons people give for believing in a god by Guy P. HarrisonWalden: Or, Life in the Woods by Henry David ThoreauExile and the Kingdom by Albert CamusOur Inner Ape by Frans de WaalYour Inner Fish by Neil ShubinNo Country for Old Men by Cormac McCarthyThe Age of American Unreason by Susan JacobyTen Theories of Human Nature by Leslie Stevenson & David HabermanHeart of Darkness by Joseph ConradThe Stuff of Thought by Stephen PinkerA Thousand Splendid Suns by Khaled HosseiniThe Lucifer Effect by Philip ZimbardoResponsibility and Judgment by Hannah ArendtInterventions by Noam ChomskyGodless in America by George A. RickerReligious Expression and the American Constitution by Franklyn S. HaimanDeep Economy by Phil McKibbenThe God Delusion by Richard DawkinsThe Third Chimpanzee by Jared DiamondThe Woman in the Dunes by Abe KoboEvolution vs. Creationism by Eugenie C. ScottThe Omnivore's Dilemma by Michael PollanI, Claudius by Robert GravesBreaking The Spell by Daniel C. DennettA Peace to End All Peace by David FromkinThe Time Traveler's Wife by Audrey NiffeneggerThe End of Faith by Sam HarrisEnder's Game by Orson Scott CardThe Curious Incident of the Dog in the Night-Time by Mark HaddonValue and Virtue in a Godless Universe by Erik J. WielenbergThe March by E. L DoctorowThe Ethical Brain by Michael GazzanigaFreethinkers: A History of American Secularism by Susan JacobyCollapse: How Societies Choose to Fail or Succeed by Jared DiamondThe Battle for God by Karen ArmstrongThe Future of Life by Edward O. WilsonWhat is Good? by A. C. GraylingCivilization and Its Enemies by Lee HarrisPale Blue Dot by Carl SaganHow We Believe: Science, Skepticism, and the Search for God by Michael ShermerLooking for Spinoza by Antonio DamasioLies and the Lying Liars Who Tell Them by Al FrankenThe Red Queen by Matt RidleyThe Blank Slate by Stephen PinkerUnweaving the Rainbow by Richard DawkinsAtheism: A Reader edited by S.T. JoshiGlobal Brain by Howard BloomThe Lucifer Principle by Howard BloomGuns, Germs and Steel by Jared DiamondThe Demon-Haunted World by Carl SaganBury My Heart at Wounded Knee by Dee BrownFuture Shock by Alvin Toffler

OTHER PAGES WORTH EXPLORING
Banned Book ListOur Amazon.com SalesMassimo Pigliucci Rationally SpeakingOnline Reading GroupTop 10 Atheism BooksFACTS Book Selections

cron
Copyright © BookTalk.org 2002-2011. All rights reserved.
Website developed by MidnightCoder.ca
Display Pagerank