Notices
Results 1 to 14 of 14

Thread: Human diaspora

  1. #1 Human diaspora 
    ox
    ox is online now
    Forum Cosmic Wizard
    Join Date
    Mar 2009
    Posts
    2,062
    How did humans find their way from the African jungles and plains to eventually end up back in the Amazonian rain forest? I've heard that they used boats to go from say Australia over the Tasman Sea to New Zealand and then on to South America. They must have been expert navigators as well as daring explorers.


    Reply With Quote  
     

  2.  
     

  3. #2  
    Forum Cosmic Wizard i_feel_tiredsleepy's Avatar
    Join Date
    Mar 2008
    Location
    Montreal
    Posts
    2,256
    Generally most people accept that they crossed the berring straight from asia when there was more ice cover and less water, and then migrated south from North America. This doesn't have to be a single event though, it could have happened multiple times, and probably did. From New Zealand to South America makes less sense than directly from Africa to South America considering the distances involved.


    Reply With Quote  
     

  4. #3  
    WYSIWYG Moderator marnixR's Avatar
    Join Date
    Apr 2007
    Location
    Cardiff, Wales
    Posts
    5,810
    also. consider that humans are found in the Americas from about 12,000 years ago, whilst New Zealand saw its first human occupation just before 1000AD ...
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
    Reply With Quote  
     

  5. #4  
    Forum Radioactive Isotope skeptic's Avatar
    Join Date
    Nov 2008
    Location
    New Zealand
    Posts
    4,840
    As a New Zealander, let me comment. Getting to NZ was just part of a greater Polynesian migration right across the Pacific. Even though this was a stone age people, they were highly sophisticated in both boat building and in navigation. They constructed giant double sailing canoes by digging out great logs using both fire and quartzite adzes. Sails were made by weaving flaxes into a type of cloth. Navigation was by the moon and stars. They built star 'maps' from wooden frames with strings across, so that the intersection points of the strings marked out the positions. Modern anthropologists have repeated many of the voyages using the same tools as the old time Polynesians and found that both vessels and navigation methods were practical.
    Reply With Quote  
     

  6. #5  
    Forum Isotope Bunbury's Avatar
    Join Date
    Sep 2007
    Location
    Colorado
    Posts
    2,590
    The Bering Strait route (which was across a land bridge that no longer exists) is by no means the only hypothesis. There are Atlantic and Pacific water routes postulated, and there are significant problems with the Beringia hypothesis. Good summary in wiki...

    http://en.wikipedia.org/wiki/Models_..._the_New_World

    The 13,500 year old dating of Monte Verde is very interesting, since it predates the Clovis culture.
    Reply With Quote  
     

  7. #6  
    Forum Freshman
    Join Date
    Aug 2009
    Posts
    16
    People could move through oceans as early as first du-outs were constructed. Willingly, or unwillingly pushed by tides and winds. Intuits have a long tradition of boat building, some ten thousand years, and their canoes are very good and seaworthy so I canít believe that the only route to the Americas went through the Bering Straight. And also people were capable of reaching Europe from America along the Arctic, the more so that there are natural waypoints like Greenland and Island. And islands in the Atlantic, between South America and Africa, to consider the route across South Atlantic, though, I donít think that there were any crossings from Africa westwards that successfully established settlements which continue until today.
    Reply With Quote  
     

  8. #7  
    Time Lord
    Join Date
    Apr 2008
    Posts
    5,328
    Oldest remains in the Americas suggests that we came during the glacial maximum. I doubt that's coincidence.

    Why then? Environmental reasons could be: cold brought more suitable habitat ( :? ), or forced migration (as if "migration" really happens over hundreds of generations), or lowered sea level to reveal bridges and waypoints (I like this one: that Aleutian chain became a nearly unbroken isthmus populated by seal, crab, shorebirds, etc. and cut off from cold Arctic water is highly suggestive IMO). Technological or cultural changes may have been decisive too. If the presence of ice sheets meant humans learned to exploit marine resources, we could run with that knowledge. Run down the coasts to Monte Verde, Chile, and spill nine species of seaweed around the firepit.

    Coastal migration is an exciting hypothesis because it's almost teleportation. For example near the end of the sea otter pelt trade, Aleut, having exhasted their local supply, ventured as far south as San Diego. Granted they had guns by then, but they did come and hunt in the same whale-hide kayaks they had lived by for thousands of years.
    A pong by any other name is still a pong. -williampinn
    Reply With Quote  
     

  9. #8  
    Forum Radioactive Isotope skeptic's Avatar
    Join Date
    Nov 2008
    Location
    New Zealand
    Posts
    4,840
    There are indications of early colonisation of North America during the glacial period by a European culture. The theory is that these guys crossed the Atlantic in the same way Inuits got around. That is, they loaded all their belongings (especially stone tools) into skin boats, and paddled. They would have kept to the edge of the ice, and pulled their boats up onto the ice at night to sleep, and during storms. They would survive by hunting seals. They probably did not even think of themselves as travelling - just hunting along the ice edge. However, given enough time, they could readily cross the Atlantic and colonise North America.

    The evidence for this is two-fold.
    1. Stone spear points found in America that are almost identical to stone points found in the south of France.
    2. A particular genetic marker found among native Americans aroud the Great Lakes area and also found in parts of Europe.
    Reply With Quote  
     

  10. #9  
    Time Lord
    Join Date
    Apr 2008
    Posts
    5,328
    Quote Originally Posted by skeptic
    They would have kept to the edge of the ice, and pulled their boats up onto the ice at night to sleep, and during storms.
    Fascinating! So sea ice facilitated a mode of migration which would not possibly occur in warmer times.


    The ideas about just how maritime humans used ice, though, I'm a bit doubtful of.

    Iceburgs and pack ice are colder than seawater, and the air around iceburgs is damn cold. So we would not sleep comfortably on them. I think people accustomed to life in a small covered boat would rather stay onboard at night.

    As for storms, every sailor knows the great danger of storm is that wind and waves can run the vessel aground - e.g. over a nearly submerged block of ice or against the "shore" of ice. And ice including huge iceburgs does tend to break up during storms - no good clinging to wave-washed ice when it calves and proceeds to roll over. To survive storms, with boats intact, these people are better off paddling away from shore. There, the high swells themselves don't harm small boats like they do large ship hulls. The wind doesn't threaten oars like it does sails. Just keep bailing.

    People may have ventured onto ice to hunt seal, bear, etc. All mammals that breathe air and either haul up onto ice - where they're vulnerable - or maintain breathing holes through the ice where they're easily speared.

    What is most useful about sea ice though is that it's fresh water. Drinking water is a precious commodity at sea and the supply limits just how long one can travel.
    A pong by any other name is still a pong. -williampinn
    Reply With Quote  
     

  11. #10  
    Forum Radioactive Isotope skeptic's Avatar
    Join Date
    Nov 2008
    Location
    New Zealand
    Posts
    4,840
    Pong

    I seriously doubt that this theory would have come about, except for the example of the Inuit. They have been living at the edge of the ice each winter for thousands of years, and using their skin-clad boats for travel. It is not a comfortable mode of existence, but clearly do-able.
    Reply With Quote  
     

  12. #11  
    Forum Freshman
    Join Date
    Aug 2009
    Posts
    16
    Lack of drinking water would be the only restriction to cover such large distances in skin boats or any fitting craft, whether with or without sails Ė but a decisive one. So, I donít see a chance for anyone to survive a South Atlantic trip from Africa to America, unless a method of removing salt was known and then forgotten, though itís difficult to imagine that such a vital knowledge would ever be lost. There is plenty of food in the sea. It would be possible for skilled hunters to live off whatís in the water for months, not comfortably of course, but still keep moving; If not for the lack of drinking water. In northern zones any contact with water such as submersion, far away from land would be lethal down to hypothermia, though with luck and on calm seas people could stay afloat and alive for long.
    Reply With Quote  
     

  13. #12  
    ox
    ox is online now
    Forum Cosmic Wizard
    Join Date
    Mar 2009
    Posts
    2,062
    Consider this: In Alan Moorehead's book 'The Fatal Impact' he refers to the aboriginees of Australia. When early explorers arrived they anchored their ship in the bay and could see aboriginees on the shore, but these took no notice of the arrivals, even though it should have been the most momentous event in their lives. It's as if their ancestors had undergone a dramatic migration only for their descendants to revert back to a bygone age. Surely this also happened in South America where an intelligent people somehow found their way back in time to live in a tropical rainforest. What puzzles me even more is why stories of these ancient migrations appear not to perist among the indiginous tribes.
    So does this reversal of evolution have a name? Could it happen again? Remember the Morlocks and the Eloi in Wells' Time Machine.
    Reply With Quote  
     

  14. #13  
    Forum Cosmic Wizard paralith's Avatar
    Join Date
    Jun 2007
    Posts
    2,190
    Quote Originally Posted by ox
    Consider this: In Alan Moorehead's book 'The Fatal Impact' he refers to the aboriginees of Australia. When early explorers arrived they anchored their ship in the bay and could see aboriginees on the shore, but these took no notice of the arrivals, even though it should have been the most momentous event in their lives. It's as if their ancestors had undergone a dramatic migration only for their descendants to revert back to a bygone age. Surely this also happened in South America where an intelligent people somehow found their way back in time to live in a tropical rainforest. What puzzles me even more is why stories of these ancient migrations appear not to perist among the indiginous tribes.
    So does this reversal of evolution have a name? Could it happen again? Remember the Morlocks and the Eloi in Wells' Time Machine.
    I haven't read the book, nor am I familiar with this moment in history, but why should it necessarily be the most momentous in the lives of the aborigenes? Perhaps they were used to other people stopping by in boats, even if the boats they'd seen before weren't quite as big as the boats used by European travelers. I also don't see why you think they'd reverted in any way - when their ancestors first set out to sea, it probably was to find a new place of their own to live. They found it, so they had no more need for sea travel. Though they may have lost traditions of boat making because they didn't need it anymore, that doesn't mean they are any less intelligent.

    And incidentally, because evolution has no specific direction, there is no specific name for the process by which a species may decrease in general intelligence over time.
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
    ~Jean-Paul Sartre
    Reply With Quote  
     

  15. #14  
    Forum Radioactive Isotope skeptic's Avatar
    Join Date
    Nov 2008
    Location
    New Zealand
    Posts
    4,840
    As Paralith said, evolution has no direction. There are thousands of species that are the result of evolution from a more complex to a less complex form, especially among parasites.

    Have you read Kurt Vonnegut's book Galapagos? In this, he draws a picture of the distant future in which humans have evolved into a life form similar to the marine iguanas of the Galapagos Islands, with minimal intelligence - just resting in the sun to warm up during the day, and swimming in the sea to graze on algae. While this seems unlikely, there is nothing in evolutionary theory to say it is not possible.
    Reply With Quote  
     

Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •