Tuesday, August 2, 2016

Hiking in Gondwanaland

Geologists and paleobotanists say that at one time--hundreds of millions of years ago--the major southern continents were united in one major landmass on the globe, called Gondwanaland, or Gondwana for short.  This means South America, India, Africa, Australia, New Zealand, Antarctica... Have you ever wondered at how the outlines of eastern South America and Western Africa line up?  There's a very good reason for that!

On what basis do they make this assertion?  Well, lots of reasons...for one, the continuation of swaths of the same rock types across the continents.  Another clue is in the types of plants that continue across continents that today are divided by thousands of ocean miles.  What a wonderful and surprising theory this Plate Tectonics is!  We've traveled thousands of miles apart, yet rock and botanical types continue across the divides.  (What about North America, you may wonder?  At one time North America and Europe were welded together in the Supercontinent Pangaea, which included what broke away as Gondwanaland.  It's really interesting to note that the most ancient rock types in our Appalachian chain continue into Canada, through Nova Scotia--and they match up exactly with rocks in Scotland.  Wow!)

Barry and I were reminded about the fusion at one time of Australia and Antarctica.  Today as we hiked we encountered tree Giants called Antarctic Beeches.  They are found in the fossil record of sedimentary rocks in Antarctica--and this means that they lived there once.  They continue to live in the temperate rain forests of eastern Australia.  Antarctic beeches.  Wow.

1.  Barry standing outside an Antarctic beech in Lamington National Park, Queensland, near Brisbane.
2. The look of the temperate rain forest at Lamington.  It's been a real privilege to stay here and walk its paths.  Yesterday we walked 27,000 steps, today 21,000.  Thank God for good hiking boots.

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