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Politics : Evolution -- Ignore unavailable to you. Want to Upgrade?


To: Giordano Bruno who wrote (36363)5/18/2013 2:05:07 AM
From: 2MAR$  Respond to of 69300
 
Try to think, its a tree but not a tree , or a tree with vines interlooping up sideways back & forth emerging out of a teaming swamp with life going all the way up & down to probing roots. It starts off in the oceans & shallows of lakes, pools & swamps.

There are the first migrations onto land by the early amphibious tetrapods in the shallow tropical tidal zones. Just think of the penninsula of Florida or some such huge area, just how 10s of 1000s of many different little river, ponds, lakes , tidal pools & inlets would there be? Then multiply that times all the other possible habitat zones for diffferent conditions on a global scale to produced such a variety of different results, the number for possibilites becomes very great. Think of just the tip of Florida , the wide expanse of an everglade, up along the coast over to Baton Rouge, all the little river inlets, lakes etc. The Earth was a vast teaming laboratory, we're not talking some little metaphorical "Eden" somewhere in a primitive tribal imagination like the Judaic mythology but the wide expanse of an entire planet.

There's little evidence that any of the earliest tetrapods could move about on land, as their "legs" could not have held their midsections off the ground and the known trackways do not indicate that they dragged their bellies around. Their are tracks we think were made by animals bottom-walking in shallow water, we have found alot of these track traces too. Which makes perfect sense, then there's tetrapods that lost some or all of their limbs like snakes & whales/dolphins while some stayed mainly on land & others returning to semi aquatic or fully aquatic life.

What would be the reason to migrate onto land?

Prolly that there had been the rapid colonization of the coastal regions by plants , the mosses & lichens at an earlier time which provide an entirely new habitat & set of food sources . Followed by the ranging forests that just go wild & under their canopies a whole new worlds open up with the added oxygen to the atmosphere setting off huge changes extremely fast. Plants evolve very fast.



To: Giordano Bruno who wrote (36363)5/18/2013 2:15:13 AM
From: 2MAR$  Read Replies (1) | Respond to of 69300
 
Short answer, they were partially floating using buoyance of water in the shallows.

think.

( or better yet, read)