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What are we evolving into?

  1. Sep 2, 2006 #1
    Lets say that human race never gets destroyed, we keep evolving, would we one day be free of all deseases because our immune sys. be really strong? Would we be really smart?(why) I always see that as we evolve, people imagine we get smarter. What would cause us to get smarter? Maybe because we push our brains more every generation but I dont think genetics have anything to do with it.
     
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  3. Sep 2, 2006 #2

    selfAdjoint

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    Well right at the moment the adaptive gradient seems to be set against smarts. Smart women who have the freedom to do so elect to have fewer kids which biases the population growth toward those who are either not smart or not free.

    In the future there will be a period, at least of energy shortages, fresh water shortages, and rampant diseases, spread by modern global communications. AND ability of small terrorist groups to generate kiloton explosions. Those who survive this challenge best will differentially dominate the population of the future. It seems to me here and now that it will be those who best can live in an organized polity; no-one is going to be able to do this on their own, goodbye Rambo. Whether smart people can find a niche, as the Ashkenazi Jews did during the black death and the thirty years war, we don't know.
     
  4. Sep 2, 2006 #3
    As we are evolving, I have seen, heard, and read, that we become smaller and smaller physically, and get smarter. Well, first of all, that doesn't make sense to me. What is causing us to be that way? Second, if we aren't getting smaller? What exactly are we evolving into?

    I know you said that right now, we are getting more duffer in a way, but if it was just 1 familiy and if we just focus on 1 generation, in what way would we be evolving? I think I know that our immune sys. is getting stronger but so are the viruses.
     
  5. Sep 2, 2006 #4

    selfAdjoint

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    That small big-headed idea was an old one from the 1940s and 1950s, based on very shallow thinking. It's important to realize that evolution doesn't have a goal, it just a series of reponses to various challenges and it goeth where it listeth, like St. Paul's wind.

    It wouldn't be clear. You could look at the mother's alleles (gene types) and the father's, and see how they were expressed in the children, but even this would be oversimplified in the modern view becoause of things like epistatsis (proteins influencing genes) and recombination (jumping genes). The more people find out about genes the more complex the picture and the dynamics get.

    Evolution is like the minute hand of a clock; you can't see it moving but over an hour it goes clear around the clock.
     
  6. Sep 3, 2006 #5

    jim mcnamara

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    Natural Selection doesn't have predefined goals or directions. It isn't a vector - something with magnitude and direction.

    It is simply random environmental or social (as SA suggests) factors that create (or do not create) differential reproduction in populations.
    Populations can:
    stay more or less at "starting values" for long periods,
    drift randomly,
    go extinct,
    (fill in the blank with whatever you like).

    SA above kinda took the (fill in the blank) option to make a point.
    For humans, I personally favor the 'go extinct' option. In terms of probablilty based on observations of past species, at least, the 'go extinct' option is by far and away the most the most likely. Most species go extinct.

    Therefore, humans will evolve (or not), eventually reach a dead-end, and go extinct. Period. Several other species in the Homo genus have already preceded us into extinction.


    That isn't very much fun, is it? -- so go ahead and speculate.
     
  7. Sep 3, 2006 #6

    DaveC426913

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    As we have concluded, evolution does not have a direction or predictable outcome.

    In the same way, a 'dead-end' is a meaningless concept. There is no such thing as a dead-end, except inasmuch as a species cannot continue to survive and breed (because of natural or competitive barriers).

    Why would humans cease to be able to breed? Just because their evolution is going nowehere prediictable does not mean we won't continue to breed. Unless we were blown back an ice age civilisation and lost our smarts and technology...
     
  8. Sep 3, 2006 #7
    I read in a book that evolution is actually cycle. Is that another gossip?
     
  9. Sep 3, 2006 #8

    DaveC426913

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    Can you be more specific?

    If I were to interpolate the likely meaning of that, I would strongly lean toward nonsense.
     
  10. Sep 4, 2006 #9

    saltydog

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    We're so anthropocentric aren't we: purposes in life, goals, direction, and meaning. That's all good I think from a Darwinist perspective. Hey, whatever works in the interest of survival and reproductive success. Religion works too. Stripped however of it's humane trappings lies a dark, indifferent reality: chance caught in the breeze. But that's a harsh finality difficult to stomach for fragile creatures such as we, de-selective to do so I would think in fact. So we candy-coat it with faith, with purpose, and sanctity of life as strategies for survival.
     
    Last edited: Sep 4, 2006
  11. Sep 5, 2006 #10

    DaveC426913

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    Point of order.

    This thread has nothing to do with "anthropocentrism", "purposes", "meaning", "religion" or "candy-coating".

    The question posed is not a philosophical or theist question, nor is it even a humanistic question. It is simply about the 'direction' of evolution. Refreshingly so in fact.

    Please don't hijack it with what appears to be a kneejerk 'purpose in life' response.
     
  12. Sep 7, 2006 #11

    saltydog

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    I yield to you. Sorry guys for poisioning your thread. I do very much believe in staying focused on the topic of discussion and failed here. Will try to do a better job in the future.
     
  13. Sep 7, 2006 #12
    I think that medicine had created an model of how the human being should be like. Aberrations to what it is consider "normal" or "by the book", like a literally third eye, are removed by surgery and fixed. Our evolution is then slowed or stopped because these mutations are not given a chance.
     
  14. Sep 7, 2006 #13

    Another God

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    [C It is simply about the 'direction' of evolution. [/QUOTE]
    However it must be remembered that Evolution has no direction. The Evolutionary process is an entirely reactionary process. It may be interesting to propose potential outcomes, but it is no more than fun speculation about what the future holds. In order to do so you have to guess at whether a virus will strike or not, whether WW3 breaks out, whether we will invent a renewable energy source, whether we will expand into space... etc etc etc... Once you have guessed at the future environment, then u can try to guess how our biology might react over the course of many generations.
    Surgically altering a mutation does not affect the genetic profile of that individual and hence does not affect the inheritence of that same mutation.

    Most disfigurations which are operated on are caused by developmental issues though, not genetic ones.
     
  15. Sep 12, 2006 #14
    I actually think humans are evolving to be more susceptible to diseases of most kinds for the following reason:

    Medical improvements allow us to treat those with diseases that should be fatal into diseases that are not fatal. For example diabetes type I , we have provided treatments to this disease and allow those with the disease to have children and pass on the "defective" genes. This is true for other genetic abnormalities that decrease the chance of survival without the use of medical support.




    However I must say that I agree with the ideals of doing all we can to help everyone.
     
  16. Sep 12, 2006 #15

    Another God

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    Just because we are more able to survive a negative does not mean we are directed towards that.

    I mean, being able to survive more diseases doesnt create a selective pressure that makes us more susceptible to diseases. What it does do it create more scope for variability. Variability is very important for when a selective pressure is applied because there are more options and more chance of one or a million humans being adapted...
     
  17. Sep 13, 2006 #16
    I agree with you when you say there is more variability when we use medical applications to aid people with diseases that cannot be supported without them. Who knows what selection criteria may be called upon by our environment in the future.

    However, understand that 'natural' selection did not choose those with these diseases to survive, they are only 'artificially' surviving due to our medical advances.

    Also it is not always true that being able to survive more diseases doesnt create a selective pressure that makes us more susceptible to diseases. Because I would argue that certain diseases do make you susceptible to other diseases.
     
  18. Sep 16, 2006 #17
    I have a question about human evolution and so instead or making a new thread I'll ask it here.

    Recently, I was watching a news story on how flip flops are causing stress fractrues in insteps of feet because of lack of support. But why is this happening now? Prehistoric humans ran with no shoes so are we getting weaker or are the people with weak bones just surviving nowadays?
     
  19. Sep 16, 2006 #18

    selfAdjoint

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    The case of walking or running in flip-flops is quite different from the case of walking or running barefoot. Also notice that the paved surface we use much of the time did not exist in prehistoric times.
     
  20. Sep 18, 2006 #19
    One more thing concerning the difference between 'prehistoric' or 'pre-footware' man and today's man (post-footware.) Hard surfaces can be the bane of our bones since these surfaces don't absorb much of the impact like dirt or grassy areas did for pre-footware man.

    The notion of land being covered by concrete and asphalt and small patches of dirt such as those found in back yards is an amazing one. Think about that next your walking around in the city. Everything is covered by 'artificial' man-made materials.
     
  21. Sep 18, 2006 #20

    radou

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    We were devolving since the point we started to evolve. That's the human paradox. :biggrin:
     
  22. Sep 18, 2006 #21

    selfAdjoint

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    There is no such thing as devolving, since there is no predetermined direction for evolution. We change in random directions, in random ways, and some of those changes prove more beneficial, in the strictly limited sense of fostering more offspring, than others.
     
  23. Oct 3, 2006 #22
    De-evolving simply isnt possible.. something making us LESS adaptable to our environment would last a single generation.. "maybe" a few before the organsim fails to procreate and pass on the "misguided" gene. Technology may be able to keep that human alive.. but for how long? And their offspring..?

    While mutation may be random.. we "change" as a result of our environment. The change is NOT random... and will only express itself because it offers a selective advantage.

    There are TWO forces at work here.. their mechanism for action have NOTHING to do with each other.. the mutation is random, the environmental pressure allowing that mutated gene to express itself is not random.

    Humans are a VERY unique species in that MANY things the SHOULD give us a selective advantage DO NOT. (because we have a misguided sense of what selective advantages are.. i.e. nice guy syndrome)
    Higher intelligence for example.. really reduces your chance of creating offspring.. the smarter you are the less likely you are to have children and when you do.. you will have fewer.

    Things we think should hurt our chances, in fact may help.. stupid people, obnoxious people, (lets say of course that I am speaking of genetic traits leading to lower intelligence and/or obnoxious behavior.. ie emotional control centers in the brain).. people like that usually breed like rabbits.

    and lets face it... stupid people have stupid kids.. cry egaltarianism all you want. You're wrong. All humans are NOT equal in mental capacity and if you beleive that tripe.. well I'll stop there.

    So stupid kids.. more bad choices... more offspring they cant afford but as a society.. we have social programs to feed the young stupid offsping of the stupid. While the smart have few children and are expected to fend for themseleves.

    Sounds harsh and mean.. but after a few hundred generations what do you think the result would be.

    It would be like a social program for fat, slow cheetas. the fast cheetas are treated exactly as they are now.. all their environmental factors working to keep them in check.. but the fat slow, gentically gimped cheetas.. we'll we feed them.. give them cheetah porn to watch .. and next thing you know.. you have.. a hundred thosand fat lazy cheetahs and a few thousand fast ones.

    in a much more complex sense thats whats happening to humans...

    Things that would absolutely obliterate other species.. are simply blips on our radar because of technology and medicine. With our highly mobile culture.. what do you think would happen to humanity if we didnt have acvure for the plague in this age? It would spread a thousand timesfaster than in did in the past.

    If humans completely lacked technology... we would probably have super human immune systems because only those capable of surviving thousand sof generations through countless straines of every nasty bacteria and virus would live long enough to procreate. We would probably have near super human healing ability... asuming you could get the calorie content required to sustain it. (the fantasy example of "Wolverine".. do you have any idea how many calories daily he would have to consume to maintain a heling process that fast? A major injury would take tens of thousands of calories to correct)

    edited to add.

    One thing we fail to consider are the SOCIAL pressures acting upon evolution. Humans are social creatures.. with many genes controlling behavior and attitude. We make the mistake of only considering "physiological" changes when speaking of humans and evolution.

    Have any of you ever considered that we ARE actively evolving.. but purely in a social senseand in our ability to cope with a large complex social infrastructure? genes that control, our ability to communicate, exhibit body language (emotional-physical ceneters in the brain) are changing due to environmental pressure.

    In a crude sense we ask ourselevs many times "how come women like bad men" or why "sluts" get more sexual attention.. did it ever occur to you all that that things that create those behaviors are giving their host a selective advantage...

    while all our nerdyness and smarts is just killing us off. LOL.
     
    Last edited: Oct 3, 2006
  24. Apr 13, 2007 #23
    But being able to develop technology is the selective advantage that has helped us survive and spread and if we hadn't got technology, other creatures with nature-given weapons, coating for low temperatures, protection against other animals would have beaten us and we wouldn't flourish as we do now.
     
    Last edited: Apr 13, 2007
  25. Apr 13, 2007 #24
    Greater technological advancement in the human population have often and will often lead to radical changes in the microbial soup. This has been made abundantly clear during the past 50 years with the emergence and modification of bacteria and viruses. Examples of this is HIV, MDR STDs, MDR Tuberculosis and Cholera, Ebola, Lassa, Marburg, avian influenza and the list goes on.

    Hardly. The technology you are referring to has only existed for about 200 years. Add that to the fact that life has been on this planet for more than 3 billion years. We live in a microbial soup. Humans have a hard time imagining that they are just one piece of our general ecology in which they life and in fact, they are food for literary millions of microbes.

    Even if the human immune system got stronger, the pathogens would also improve their method of spread and avoidance of detection via passing of modified plasmids etc. Evolution does not have a goal or predetermined direction. Specie 1 can be annihilated by the spread of specie 2, which in turn is overtaken by Specie 3. There is nothing that stops specie 1 from winning the competition over specie 3 if the ecology is favorable in a later stage. Evolution is not a process where everything gets 'better' on an absolute scale, it is only in relation to the environment.

    We have not yet begun exploring the multitude of bacteria, viruses or parasites that exists in the world. Technology is a double-edged sword. Before the age of antibiotics, people where dying fast of diseases that, after the arrival of antibiotics, were considered mere easily treatable nuisances. Today, we see more and more of them coming back in a MDR form.

    Evolution is a constant process. Take for instance the shift in regional health standards and life quality. The third world has the largest amount of starving and subsequently dying population, while the obesity levels in the worlds industrial nations are rising quickly due to change in social conditions.
     
    Last edited: Apr 13, 2007
  26. Apr 13, 2007 #25

    sas3

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    You also need to consider the fact that for the first time in history, we (the human race) have the ability and understanding to change our own “blue prints”
    I think this will have a profound affect on where we are headed. We have become (for lack of a better word) “Gods”
     
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