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Why do biologists talk about appearence of design ?

  1. Oct 2, 2011 #1
    Why do biologists talk about "appearence of design"?

    Hi all,

    It's really puzzling to me that various biologists say that nature appear to be designed. I'm not sure if you guys have seen the same quotes, but here's one:

    "Biology is the study of complicated things that give the appearance of having been designed for a purpose.” (Dawkins, The Blind Watchmaker, p. 1)

    To my eyes, the natural world looks obviously non-designed. When I look at a tree, it doesn't look like anything someone would design. I think of design as something more static, but a tree is growing every day. The things that we humans design generally don't keep on growing. Same goes for animals etc.

    Why does Dawkins and others use this phrase? Does he really think that nature looks designed??? Or is it just a rhetorical trick to appeal to people who do?
     
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  3. Oct 2, 2011 #2
    Re: Why do biologists talk about "appearence of design"?

    I believe it's a reference to the complexity of living things. Random processes generally will not give rise to something as complex as a tree. Think about how complex a tree is, it has a vascular system, it uses energy form the sun to manufacture sugars, etc. We are correct in believing such complex things can't just randomly assemble. A car will not just randomly assemble from the atoms that make it, and a car is a complex piece of equipment that performs various functions. That is why we could be forgiven for thinking that a living organism had to be designed: thought had to go into making it, since its so complex and performs complex functions. However, evolution by natural selection is an explanation for how such complex living things can arise without someone designing them (plus abiogenesis, not sure if its included in evo). They look like they were designed for the reasons stated above. However, note that natural selection in NON-RANDOM.
    This may be a confusing explanation, in which case I apologise.
     
  4. Oct 2, 2011 #3

    Pythagorean

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    Re: Why do biologists talk about "appearence of design"?

    Dawkins is setting up for a religion vs. science argument, naturally.... his audience is people from both sides who are emotionally engaged in the social dichotomy. I mean, come on, he goes on Fox News to argue with O'Reily and Beck... he's obviously part of the shock TV culture if he's willing to wrestle in the mud with them.

    Hitchens was way more entertaining, imo.
     
  5. Oct 2, 2011 #4
    Re: Why do biologists talk about "appearence of design"?

    I'm definitely no expert, but your analogy between natures "construction" of objects and human's construction of objects maybe should take into account the "structure complements function" concept, and that although nature has composed a number of uniquely functioning objects, far more than humans can fathom, the similarity amongst US and nature, is the aim for the "structure and function" to progressively complement one another BETTER and BETTER. Naturally, they say things tend toward entropy, but I guess in sense, that to organize matter is to keep balance in order to sustain life and ultimately and innately humans realize that nature sets the best example in balancing by a number of means. A human may not share the appearance of a laptop computer. One is even considered living and the other NONliving (BIG difference lol), but both utilize/require flowing energy, both are composed of multiple structures to suit their respective purpose, . . Like I said though, I'm no expert (not even close), but everything is composed of the same matter and energy that is recycled and exchanged from one source to another and while a laptop and human ultimately carry out different task in life using different material, the WAY they conduct them is the same. . . if that makes sense
     
  6. Oct 2, 2011 #5
    Re: Why do biologists talk about "appearence of design"?

    My opinion is with the perspective that I just don't think Dawkin's meant "designed" by a being or supernatural force/God to try to appeal to certain ppl, I take/took it as his reference to the relationship and behavior of the material that has formed the universe/all things. I think it's a bigger concept that goes beyond humans as most things do seeing as we're a miniscule factor in the operation of the universe.
     
  7. Oct 2, 2011 #6
    Re: Why do biologists talk about "appearence of design"?

    I can't stop, lol, but I mentioned entropy constantly being the propensity to disassemble, basically, but also constantly trying to counter that with organization is what creates the "flow" of energy between matter. . . or else, everything would be stagnant. . . everything was "designed for a purpose", the purpose being for the object to ultimately keep it's own share of energy flowing, the best way possible, . . and it's design/structure allows it's most effective functioning to achieve this
     
  8. Oct 2, 2011 #7

    bobze

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    Re: Why do biologists talk about "appearence of design"?

    They aren't talking about religion, entropy or complexity--No offense to other posters :)

    When a biologist says it "appears designed" they are referencing selection. Because of differential survival and reproduction of varying forms, structures "appear" which have a "purpose". All they are saying is that things, on a cursory glance, appear designed because of selection.

    Consider an example; The hand. Overtly it may look like a hand was "designed" to grasp, hold, etc--All those functions that hands serve for us. But, why does a hand look designed for those tasks? Is it because a designer "made" us with hands? Once upon a time, scientists and naturalists believed this was the answer.

    What Darwin came along and showed us (not the origin of species, he never actually answered that question) was how adaptive evolution happens--Via natural selection. It is therefore not incorrect to say a hand is designed, so long as you understand that the designer is not an intelligent agent--Rather the blind process of natural selection.

    Back to hands--The answer to the question is then, that through successive generations natural selection built upon prior "designs" to solve the problem of hands.

    So this might then confuse some readers at this point--You may say, "well bob if selection is designing these features of organisms, how do we know that some intelligent agent isn't?"

    The answer to that is through science and understanding complexity. Something creationist constantly misunderstand when they say "ooohh, ahhh, look how complex that is--It must be designed by an intelligence"--Is that complexity does not the intelligent designer make. Quite the contrary, the hallmark of an intelligent design is a design that is simple and streamlined. It doesn't have globs of "junk" parts stuck in the middle. It doesn't have overly redundant pieces. It doesn't hijack "old parts" to implement in new features--Nature does though because it is constrained by selection. Selection acting upon variant forms.

    Consider again an example; http://en.wikipedia.org/wiki/Circadian_cycle" [Broken] are extremely sloppy, complex systems. Prone to error and problems because of this over-complexity of design. While human clocks;

    images?q=tbn:ANd9GcT5YTTte6-K2-DLjVXJ3FKuQFlwmnYtkce5nBL44F58UEWUsMJiwtowlIhKJw.jpg

    are simple, dependable, extremely accurate and even grade schoolers could be taught there inner workings.

    This is because intelligent design (humans) isn't constrained by prior "forms" of design. We simply start a new, add novelty where novelty is needed and throw out any pieces that only complicate the design.

    Nature doesn't have that luxury. It builds clocks based upon prior clocks. It can only introduce novelty when that novelty provides a statistical advantage to survival and reproduction, otherwise it runs the risk of novelty being lost--Or worse, selected against.
     
    Last edited by a moderator: May 5, 2017
  9. Oct 2, 2011 #8

    Evo

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    Re: Why do biologists talk about "appearence of design"?

    To go with what Bobze said. Dawkins said it that way to make it clear to people that think something that serves a purpose had to have been designed just for that purpose, it isn't so. The way a body is now is the result of previous designs that didn't work as well, so if a mutation comes along that works better, it might get passed on to more and more later generations until the mutation is now the norm.

    I hope that made sense.
     
  10. Oct 2, 2011 #9

    atyy

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    Re: Why do biologists talk about "appearence of design"?

    I don't understand why you say natural selection is "blind" if what it produces is "deisgned". Why not call natural selection the "intelligent agent" instead?

    So humans are intelligent in a way that natural selection isn't? Yet humans have never built a human being from scratch, which natural selection has. It's not obvious to me that a watch is a superior creation to a human being. And besides, aren't watches designed by trial and error and selection too?
     
    Last edited: Oct 2, 2011
  11. Oct 2, 2011 #10

    bobze

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    Re: Why do biologists talk about "appearence of design"?

    Because natural selection can't problem solve with foresight, only hindsight. A designer who is really intelligent could plan for problems in its designs. NS on the other hand, can only select designs which are variations of the current design and the way "it" selects those designs is through differential survival and reproduction (not each organism in a population have an equiprobable chance to survive or reproduce).

    Design in this case then, is decided by the context of the environment that variation arises in constrained by the variation that is possible in a population (not all variation is probable or even possible).

    NS then is "behind" in a sense, in that it is fitting the "current" generation to the prior generations selective pressures.
     
  12. Oct 2, 2011 #11

    bobze

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    Re: Why do biologists talk about "appearence of design"?

    Put simply, yes.

    Of course, but natural selection has also been at this game for 4 billion years. Humans have been at this game a very short time. In that short time (consider that modern genetics is only couple decades to half a century old tops) humans have done some pretty incredible feats of genetics.

    By the same token, has natural selection ever made a glowing rabbit? No? Humans have. NS isn't capable of that kind of design because of constraints on novelty available to a population. Humans, a real intelligent designer, are not.

    I didn't say this so please don't put words in my mouth. I said intelligently designed things are simple--Not complex. That is the hallmark of intelligence in design, not natural in design.

    However, for your statement though, I would argue that watches are superior time devices to natural circadian rhythms. If you doubt that, then you need to study a bit all the short-comings "natural rhythms" can have. Not only that, but the precision at which each keep time as well. If you doubt that as well, ask any woman you know what is more precise her watch or the day and time she starts menstruation.

    Sure they can be. No one said that intelligence cannot design by trail and error. The difference is, and this is important (enough for me to boldface), intelligent designers can scrap plans and take it "back to the drawing board"--Selection can only work on variation constrained by the population it exists in.

    Example time again. Suppose you have a problem, you want to build a Jet engine--Yet only prop engines exist. Would you, stepwise build a working jet engine from that prop engine making sure every in between step is functional? No, you'd be called crazy!

    However, that is how selection must work--It doesn't have the luxury of "starting over". To solve an evolutionary problem (presented via selection from the environment) it must act upon variation in a population--recall that not all variation is probable or possible.

    Were selection as smart as me then, it certainly wouldn't have dropped my nuts through my abdominal fascia, apaneuroses or muscles. Selection would have simply "redrawn" a human male where the nuts didn't have to take such a silly descent.

    A solution to natural selection is a solution, it doesn't matter if it is a ridiculous solution or if it is a great one.
     
  13. Oct 2, 2011 #12

    atyy

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    Re: Why do biologists talk about "appearence of design"?

    But human beings are designed by natural selection. So why aren't all the designs of human beings also designed by natural selection?
     
  14. Oct 2, 2011 #13

    bobze

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    Re: Why do biologists talk about "appearence of design"?

    Read what you wrote again out loud, I'm not sure I am following your question. Human being's as a population (really the statistical averages of allele frequencies we call our "gene pool") are designed by selection. The actual "design" of a human occurs as gradient-directed development in utero (of course the governing rules of those gradients are the result of selection acting historically upon our ancestral populations).
     
  15. Oct 2, 2011 #14

    Evo

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    Re: Why do biologists talk about "appearence of design"?

    It's not *designed*. Let's stop using the word designed, because nothing in the human body is designed. The OP asked why someone would say a body part "appeared" designed. That question was answered.

    To make it really, really simple, the body has a set of "instructions" for lack of a better word, so it knows what a body needs and what goes where.

    Sorry Bobze, I'm just trying to prevent people from latching onto a misunderstanding of design as a process that is being guided by some sentient force.

    Natural selection is not a "thing" that can have intelligence.

    No natural selection doesn't build or actively (knowingly) make changes.

    Your post #11 is an excellent explanation, btw.
     
    Last edited: Oct 2, 2011
  16. Oct 2, 2011 #15

    atyy

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    Re: Why do biologists talk about "appearence of design"?

    The part I don't understand is: do intelligent agents exist? Do we have formal criteria for saying x is intelligent or not intelligent?

    If no such criteria exist, then the question is moot.

    If such criteria exist, then we should be able to apply them to natural selection, assuming natural selection exists (in some limit?), and determine whether natural selection is intelligent.
     
  17. Oct 2, 2011 #16

    Evo

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    Re: Why do biologists talk about "appearence of design"?

    I don't know what bobze thinks of this video, but I find that it's easy to understand for people that don't know biology.

     
    Last edited by a moderator: Sep 25, 2014
  18. Oct 2, 2011 #17

    atyy

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    Re: Why do biologists talk about "appearence of design"?

    So going between Bobze and Evo's contradictory answers, let me suggest the tradition textbook term for "design" is "adapted". In this framework, reproductively successful organisms are said to be adapted to their ecological niches. However, not all organisms are adapted, since the environment changes, and they are no longer adapted. Adaptation seems to be a "subjective" term, since it depends on the time and the time scale of observation. However, thermodynamic equilibrium is also a similarly "subjective", so that is not necessarily a problem.

    It is unclear to me that natural selection is "unintelligent" for some definitions of "intelligent". There is further discussion about this in http://arxiv.org/abs/1011.5466
     
  19. Oct 2, 2011 #18

    Evo

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    Re: Why do biologists talk about "appearence of design"?

    They're not contradictory. bobze is correct, I'm just clarifying that there is no "intelligent designer" in case someone would latch onto the word "design" in that sense.

    Obviously what works today may not work tomorrow if the environment changes enough.

    We're not discussing intelligence, the OP wanted to know why some people refer to a human feature as "appearing" designed.
     
  20. Oct 2, 2011 #19

    bobze

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    Re: Why do biologists talk about "appearence of design"?

    Evo and I haven't contradicted each other at all. I said back in my first post on the topic;

    The word "design" in this case is an analogy to what the process of natural selection (differential survival and reproduction) is doing.

    Adaptation is "subjective" in that variation is contextual to the environment it arises in. Consider a brown mouse population living on the forest floor where a color alleles arose that made the mice lighter, more white in color. In the context of the environment such a change certainly wouldn't be advantageous. However, in the context of a sandy beach such a change could be advantageous.

    Real example time; suppose you look at hemoglobin genes--specifically in regard to sickle cell anemia (SCA henceforth). You may say, why would such genes persist in the population. The answer would be because carriers for the trait (meaning they have one sickle cell allele and one "normal" allele) are provided a selective advantage in survival (and thus reproduction) in areas of the world where malaria is endemic. In the context of such an environment carrying a sickling allele adaptive--Living in the continental US? Not so much.

    Natural selection is not "intelligent" because it is not a living being making choices. Something very hard to understand about evolution, specifically natural selection, is that adaptation is not the goal of evolutionary change--It is simply a byproduct of differential survival and reproduction. There is no thought or choice involved.

    Some cheetahs living on the African savannah, because of mutations in their myoglobin genes, are going to be better at oxygen offloading to working muscles. Even if this advantage is .00001% better offloading, they will (statistically speaking) be more likely to catch prey whilst hunting. Thus more likely to survive and more likely to reproduce. And also more likely to feed their offspring. Because biological replication is cumulative there is a chance their offspring will inherit these traits from mom or dad. The cheetahs didn't choose to be slightly better hunters, nor did their prey choose to be eaten by this group of cheetah--However the consequence, raw survival leading to increased reproductive success, will inevitably be better represented in successive generations (because of this processes of differential survival and reproduction).

    The adaptation then (a trait 'favored' by natural selection, meaning increases that differential success) wasn't the goal or point of the change. The change was the result of imperfect replication of biological entities (genomes here) which allowed the differential acquisition of resources (prey in this case) to lead to greater reproductive success. Thus the adaptation was a byproduct of selection on that variation. No intelligence necessary.
     
  21. Oct 2, 2011 #20

    atyy

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    Re: Why do biologists talk about "appearence of design"?

    But how does one come up with a jet engine - why don't you describe it as due to random variation of ideas among the entire human population, followed by selection due to fitness for its purpose?
     
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