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Periods of Advanced evolution?

  1. Aug 27, 2011 #1
    Ok so I'm not sure if this is the right place to post this thread but I figured Earth/evolution? If not I can always move it to the biology section.

    Anyway I was speaking to a friend today who claimed that there have been periods of advanced human evolution in which the human mind over a period of 20-50 years developed extraordinarily quickly.

    The evidence for this (apparently) is that cavemen were found to draw these stick figures that we all know, gazelles, antelopes, and stick men and women chasing them with spears.

    So these drawings have been traced back to a certain date, and it turns out that (apparently) drawings dated only 20-50 years later than this were found to be extremely intricate and necessary of a capability that would should suggest evolution at a rate that is not feasibly possible.

    The theory is that some kind of extraterrestrial intervention could have been what caused this period of advanced evolution.

    I don't like this idea. But other than crazy mutations in supplements of the brain I cannot think of any other possibility, other than false information.

    What are your views on this? Anybody willing to help me debunk it?

    Thank you :)
     
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  3. Aug 27, 2011 #2

    Evo

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    Never heard of any such thing. A good way to debunk it, try finding a paper that states this from a mainstream peer reviewed scientific journal. If you can't find one, there's your answer.

    One clue might be the fact that we can't date cave paintings with an accuracy of 20-50 years.
     
    Last edited: Aug 27, 2011
  4. Aug 27, 2011 #3

    phinds

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    In addition to Evo's point there is also the fact that it's likely that there is no way to be sure two sets of drawings were done by the same tribes. In what you have said, I see nothing that could be considered evidence.

    PLUS ... when something smells of alien intervention you should start with the assumption that it is BS until firmly proven otherwise and if it is proven true, you will always find that aliens weren't the explanation. Starting with, or even seriously entertaining, a crackpot assumption without STRONG evidence is NOT a good way to get at the truth.

    Carl Sagan: Extraordinary claims require extraordinary proof.
     
  5. Aug 28, 2011 #4
    I do not know about any cave painting sequence showing an exceptional devellopment within decades, however there is a remarkable discussion if the sophistication of cave paintings is direct proof of the sophistication of the minds of those humans. The reason for this is the great drawing talent of a young autistic girl here. Apparantly her hard wiring is such that she can reproduce her visual memory very accurately, while being well below average for other intelligent skills. So that could just be true for the paleo cave painters.

    I think this thread should be in social sciences.
     
  6. Aug 28, 2011 #5
    Ok cheers guys, I've found the author of the book who made the claims: Graham Hancock's supernatural.

    Here are some points I've gathered from a few other forums:

    -: The information is false as it took far longer than decades.
    -: A possible answer is that the result of breeding with neanderthalus kicked in and so our creativity increased.
    -: the information on the painting is manipulated as it could have just been some garbagety drawer and some superior drawer.
    -: The evolution isn't that special it was just in a certain sector of the brain as the past 10,000 years has had the highest inflamation of evolution.
     
  7. Aug 28, 2011 #6
    I think that Graham Hancock has never been caught using the scientific method.
     
  8. Aug 31, 2011 #7
    I love it!

    Haroldingo - another point to consider, in the form of an analogy. If I go to the Louvre and draw a portrait on the wall next to the Mona Lisa could this be used to prove that the artistic skills of humanity have totally atrophied in half a millenium?
     
  9. Aug 31, 2011 #8
    You know it's so easy to "want" that huh? I recall Stephen J. Gould saying, "life is massively contingent". Know what that means right? It's really, really subject to chance. We see the pace of evolution on Earth because that's how it happened on Earth. But because life and the entire Universe is so massively contingent, things can be very different elsewhere. Because of that, and the extremely large distances between stars, I do not feel there has ever been physical contact between intelligent species evolving on separate planets in the entire history of the Universe and do not believe it will ever happen in the future. Probably best for us anyway since survival of the fittest doesn't stop at the stratosphere.
     
    Last edited: Aug 31, 2011
  10. Aug 31, 2011 #9
    Advanced evolution, or accelerated evolution - genetic and protein changes in the brain or in developmental processes, might not be the only explanatory hypothesis for clusters of paleontological findings.
    Let's look at the period mentioned by Haroldingo: About 50,000 years ago there seems to have been a sudden occurrence: art appeared in different forms and various places.

    Studying cognitive sciences (cultural anthropology, psychology, ethology/animal behavior, and neurobiology) leads us to recognize that brain structures can be hijacked for new uses. Since variable behavior is a hallmark of many animals, this tends to make credible the ideas of those structures being rather malleable.

    Dendritic growth to new areas can be, and be perceived as, extremely difficult. Learning things for the first time is harder than learning related skills. The initial processing routes often through the cerebellum, and memory is often retained in the hippocampal areas. When physical or mental skills/memories are well-established the localization disappears.
    It is true that certain animals are rather hard-wired to favor learning in certain ways, but our is called the cognitive niche, as we learn how to manipulate our environment through planning, strategizing, finely repeatable process.
    That's as far as we'd better go in structure - it's still quite a vaguely known geography.

    I write here because of a population ecology concept called population saturation.
    There is reason to believe that most of Homo sapiens evolution sufficient to counter a necessity for sudden evolutionary change 50kya, concerned encountering the new.

    We were surely migratory, or wanderers. At the period listed, a sudden advancement in tool creation also occurred. Since then we've had further acceleration and advancement.
    I've done a little research leading me to believe that it was at that time that population saturation in Eurasia may have occurred in the most easily habitable areas.
    This led to settling down: tribes became more sedentary as ecosystems, habitats, hunting/gathering grounds being circumscribed.
    Neighbors had also become more settled, and most of the cultural attributes developed more concretely. Trade became more established. Areas and materials conducive to art were more often accessed. Not having to avoid carrying heavy kit and more lasting encounters - more neighbors, resulted in acquisition of more varied skills from trade in networks of familiar neighbors' knowledge. (True raiding became possible, by the way.)

    Gathering observations of some other social mammals, we find huge change in behavior when populations are relatively saturated.
    Here's a story:
    Once, watching a group of 10 ravens living in a certain beach/dune stretch, I discovered that they were imitating shorebirds, poking the sand for mole crabs. No other ravens I have ever seen anywhere, share this behavior. There are parallels in the Japanese Macaque observations you may have heard of, in which learned behavior is shared among a related group.

    I don't know if this knowledge will spread to the group a few miles south, but since humans love to show things, it's likely a massive quick spread of sedentary skills did occur.

    I appreciate Jackmell's Gould quote, and have interpreted it as meaning that life is contingent upon a large number of previously contingent occurrences. It was a chemical/physical lottery.
    In social species, however, generalized communication capacity changes the odds of sudden blooming and cascading development in learning synthesizing skills from highly improbable to near complete assurance.
    Neither aliens nor new brain structures are necessary to progress and regress to us.
     
  11. Sep 1, 2011 #10

    Ryan_m_b

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  12. Sep 1, 2011 #11
    Cultural evolution, of course, occurs at even faster rates.
    Cultural evolution can be practically defined as changes in technology. It is Lamarckian!

    Evidence and analogue is everywhere in our own society, from internal combustion engines to computers and the powerful changes occurring within a generation, as new young accept and manipulate information and personal travel methods in ways unimaginable to their immediate forebears.

    Huge changes in populations and dispersal occur within time periods shorter than 50 years. Introduced literacy or educational methods and subjects promote extremely rapid development.

    Each generation perceives technological and other baselines, such as awareness of ecosystems in which they reside. While many of these can have slow periods of change, they can quickly alternate, bringing someone like my grandmother from horse and buggy into air travel, television, and home computers.


    May I remind you that genetic evolution is not progress, but adaptation to the environment in which reproduction takes place?
    The brains of present-day humans average in the range of 15% smaller than they did a mere 10,000 years past.

    Hypotheses and speculation as to why, abound:

    It may be that the population saturation I spoke of, was the primary factor in leading to relatively intense agriculture.
    Perhaps the sedentary life ceased to select big brains, and perhaps those who first raided or controlled agriculturalists violently selected for more passive peasants. It might even be that ongoing propaganda in the form of organizing religious legitimization for social stratification helped the selection further. This is not an attack, but only a reference to the necessity apparent through psychological and cultural anthropological studies that show how we must stereotype, and generalize information when involved in groups larger than the traditional bands (20-30) and tribes (certainly under 200. The number has been further narrowed to 135-170, and is often referred to as "about" 150). This appears to be the species' social limit.

    Speculation on sudden cognitive change has been popularized in books for the general public for quite a long time. Most of the rather wild speculation uses no base of physiological or anatomical evidence because brains and their neural structure do not last long after death, and don't fossilize.
    However, individual neural plasticity does occur (though ongoing neural development in adults is strongly centered in Hippocampus, mediating new memory), especially in childhood.

    Another factor one must consider in speculating on evolution, as is done in this thread, is genetic drift, occurring significantly in small populations for 4 differing reasons. These reasons affect fitness of traits arising in small populations, as we are when dealing with when looking at paleoanthropological record. Evolution can not be assessed without reference to cultural sexual selection, genetic drift, and interpopulation gene flow.

    Any size population encounters mutation bias, a physical effect, when a gene or for other discussion, a trait is not strongly selected for in a population or habitat.

    While you can debunk alien interference in several ways, changes in discovered technologies are difficult to discuss in terms of evolution without strong background in evolutionary thinking and research. It's just too complicated to make points without long research. Claims or speculations without strong peer review easily become wild and moot.

    That beast, the wild moot, inhabits most of the internet commentary we try here to escape. It's not worthy of hunting and shoots back incessantly, generally using itself as ammunition!
     
  13. Sep 1, 2011 #12
    Well, Ryan M B, Eldridge is still kicking, by the way.

    The fossil record consistently shows us that his and Gould's early '70s paper could accurately depict speciation:
    Period boundaries in geology are associated with sudden huge changes in the fossil record. However, across the earth, we do find that the replacement of genera or larger taxa can be 5 or 6 orders of magnitude slower. We cannot isolate anything other than individual finds within periods of time that are comparatively short.
    Island invasives, such as big D studied, show fast radiation into new niches.

    The more distant in time, the more fragmented or rare the find, the more inaccurate the dating.
    Replacement is slower than evolution, which as you mention, is best spoken of in geological time.

    Have you noted the recent dating of the Acheulian tool find at 1.7 mya, in which samples seemed clearly mixed with Olduwan tools?

    No one in the field speculates until multiple sources of evidence are pinned down.

    The thread, and Haroldingo's search, seems to me to be associated with debunking speculation. I always hope my own are changed through new information and clear thinking by others. I seems best to be the worst in classes, games, and company. There I learn most. Thanks for adding clarity to the discussion!
     
  14. Sep 1, 2011 #13

    Evo

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    Mike, I realize you are new here, but any time you bring up something such as your reference to stone tools, you need to post the link to the scientific study/studies also.

    Edit: Ok, I'll post it.

    http://www.nature.com/nature/journal/v477/n7362/full/nature10372.html

    And more on it.

    http://www.bbc.co.uk/news/science-environment-14754314

    But the find doesn't have anything to do with a jump in evolution.

     
    Last edited by a moderator: May 5, 2017
  15. Sep 2, 2011 #14
    Excuse me.
    Mixed in age: 1.76 mya is over 300,000 years earlier than other Acheulian finds.
    I believe the abstract itself mentions hypothesis of brain evolution leading to the more refined tool flaking.

    What i thought more interesting and also appropriate to questions of cultural versus biological evolution, are the last two sentences.

    " In either case, the Acheulian did not accompany the first human dispersal from Africa despite being available at the time. This may indicate that multiple groups of hominins distinguished by separate stone-tool-making behaviours and dispersal strategies coexisted in Africa at 1.76 Myr ago."

    Taken from:

    Christopher J. Lepre, Hélène Roche, Dennis V. Kent, Sonia Harmand, Rhonda L. Quinn, Jean-Philippe Brugal, Pierre-Jean Texier, Arnaud Lenoble & Craig S. Feibel; An earlier origin for the Acheulian; Nature 477, 82–85 (01 September 2011)
    http://www.nature.com/nature/journal/v477/n7362/full/nature10372.html
     
    Last edited by a moderator: May 5, 2017
  16. Sep 3, 2011 #15
    All good replys guys, but after some research apparently periods of time of accelerated evolution have been found to exist commonly in nature and the process is called punctuated equilibrium :)
     
  17. Sep 4, 2011 #16

    Ryan_m_b

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    I refer you to post 10...
     
  18. Sep 27, 2011 #17
    Oh my, Sorry i must've looked like a tosser :')

    I must have sourced it from this thread and got confused while trying to post it into the other.


    Sorry :(
     
  19. Sep 27, 2011 #18

    epenguin

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    Once it can be done at all, either there is a false start and a reversion, or progress would be quite rapid. And if there is really a question of biology, that there are those genetically up to it in the population and those not, then if this is a successful, advantageous breakthrough, the selection pressures change to strongly favour the smart ones.

    So theoretically there could well have been, I would not be surprised, a period of rapid change. Moreover MORE RAPID THAN EVER SINCE. Because we have not got abler since.

    It has been said that in art "Since the cave paintings we have done different things. But not better things."
     
  20. Oct 18, 2011 #19
    Hmm.... 20 years needed for mastering art... What about the same guy painting the caves as a kid and as the best artist of a whole clan? ;)

    I can think about a few more ideas:
    -change of tastes (religion/magic believes) within tribe;
    -more or less successful artist in each generation; (by occasion why do we assume that all surviving paintings should be the best? Why shouldn't survive some low quality sketches?)
    -actually capturing breakthrough in archaeological data (rather unlikely, but we theoretically could be lucky)

    By occasion - is it possible to date paintings so precisely?
     
  21. Oct 18, 2011 #20

    Evo

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    No, it is not and this has already been debunked.
     
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