Thursday, July 11, 2019

SearchResearch Challenge (7/7/2019): A couple of questions about Polynesia! (Why so long? What are those clear patches?)

I managed to find wifi! 

As I mentioned last week, I'm touring through French Polynesia for the next two weeks.  It's kind of a long way to go, but it's completely worth it.  Lots of long stretches as we sail from one island to the next.  Many of these are coral atolls, and look a bit like this as we sail by.  They're all low-slung, just barely out of the water.  You wonder how they survive when a big storm comes through.  

Rangiroa seen from the sea.

Or like this, from a satellite image:  

As I've said before, traveling is an endless source of SRS questions. Here, in this place, there are SO many things I've had to look up--my SRS skills are getting a great workout!  What kind of tree is that?  Does the nut from that tree really have fish-stupefying properties?  Really? 

Many of the things I've been seeing need a bit of research to help me understand what I'm seeing.  

This week I've got two Challenges, but on the next cycle, I'll add two more.  But for today, let's start with one slightly difficult Challenge, and a simpler one.  

1.  In researching the dates of initial colonization of Polynesian islands, I noticed a VERY strange incongruity.  Look at the map below.  The blue pins are all island nations that were first colonized around 1000AD.  The red pins (to the left of the long green line) were all colonized around 1000BCE or before.  What happened here between 1000BCE and 1000AD?  Why are the all of the blue pins MUCH later than the red pinned locations?  It's not that far from Samoa to Niue, why didn't anyone colonize that island until 900AD or so?  Generally--why didn't the Polynesians go beyond the green line for a very long time?  

2.  As we're sailing from place to place, it's not uncommon to see large patches of water without any ripples on the surface.  It's something you see nearly everywhere--it's a common effect on lakes, ponds, and oceans.  But what causes these ripple-free regions on the water?   (See below for an image that has a large Y-shaped blank area in the middle. What causes this?)  

As always, be sure to tell us not JUST the answer, but how you figured it out!  What searches worked for you, and if you spend a lot of time on a rathole that doesn't work out, be sure to leave us a comment to that effect.  We can learn a lot from strategies that don't work out.  

Search on!  



    Search request "smooth water phenomenon"

  2. I tried a first, quick search and found:

    For Q1, opened the link with the photo. And read the names of the places.

    [Tahiti Fiji colonization difference] and [Polynesians didn't go further than Samoa] and my next step is to search for each island and read how they were colonized. Thinking about this, made me remember something in Disney’s Moana but not sure if they mentioned the why about not crossing that line.

    The Great Polynesian Migration is one of the world’s most outlandish yet mysterious historical events

    [Polynesian line dividing islands]

    With [Polynesian navigation beyond Samoa]

    The Disney film Moana has drawn attention to these accomplishments and helped inform a new generation about the complexity of Indigenous astronomy.

    For Q2: [why some areas don't have ripples in ocean]

    Lanes of flat ocean surface in coastal waters

    When do waves stop forming in the ocean? There are two types of waves, a wind wave and a swell. And: Doldrums

    1. [Polynesian navigation why not further]

      Do we know why the Polynesians stopped voyaging? Also says: “...But, of course, there are places where there aren't any islands. You can draw a line through the Marquesas from northwest to southeast and if you were to set out at any angle along that line, you would have to go 4,000 miles before you found anything. Which is a very long way to go, like you're probably out of food and water at that point….”

      [polynesian colonization]

      New research indicates human colonization of Eastern Polynesia took place much faster and more recently than previously thought...

      Also interesting: “In the 19th century, Hawaiian scholars Kamakau and Kepelino attributed the discovery of Hawai‘i to a fisherman named Hawai‘iloa.” Other islands receive his children’s name.

      This is a long and interesting piece.

    2. interesting angle/approach, Ramón - big data genetic analysis element is a game shaker…
      Easter I.

      who's behind this?
      using paper mulberry plants
      using scholar
      using video

    3. The PLOS search is a good one. Thanks for reminding us of that.

  3. What kind of tree is that? Does the nut from that tree really have fish-stupefying properties? Really?
    ""If a tree falls in a forest and its seeds have poisoned you, does it make a sound?" is a philosophical thought experiment that raises questions regarding observation and perception."
    how poisons are used…
    this tree/seeds?
    details & consumption info
    video - polynesian locale Dr. Lambrinos
    tree details

    used [smooth areas of water on ocean surface]
    internal waves - see surface slicks
    math - Boussinesq approximation
    fluid dynamics…
    'Lanes of flat ocean surface in coastal waters'
    wind effect
    internal waves
    air/water interface - Woods Hole

    possible island migration inhibitor…
    Mr. Sulu, reverse course…

  4. 1. [polynesian expansion] With this I am thinking it a weather/climate situation. Indeed the clever people at Australian Geographic have nice explanation here:

    "“The winds were favourable for Polynesian migration in this couple of hundred year period,” Ian says.

    The new data suggests the epic voyage could have been achieved in a couple of weeks during these climate windows, four times faster than during other periods with less favourable wind conditions – especially when travelling in the type of canoe examined by Dilys’ team. . .Ian adds that the patterns of migration show how the Polynesian society was resilient to climate shifts, using wind conditions and canoe-building skills to colonise new lands that had more reliable rainfall.

    “Exactly at the time this is occurring, the Vikings are spreading out across the north Atlantic, the Mayan civilization in Central America is collapsing because of intense drought, and there’s societal upheaval happening right across the world due to climate changes,” he says. “Certainly the Polynesians were adaptable to these conditions.”

    Even more curious than I had thought.

    2. Lack of ripples indicates nothing is reacting with the water. Ripples indicate wind gusts / down draft perhaps. Not much tidal action here. I watch the sea everyday and this is my experience.

    jon tU

  5. …after the fire, would have thought the French would have opted for something a bit more like the pre-fire look…
    there's much to see on land too…
    pulled back so Chuck was in the frame…
    surprised Gaugin didn't paint it while he was there…
    Paul works his way in…
    ocean related