//////////////////WIKI-Carrier's constraint is the observation that air-breathing vertebrates which have two lungs and flex their bodies sideways during locomotion find it very difficult to move and breathe at the same time, because:
the sideways flexing expands one lung and compresses the other.
this shunts stale air from lung to lung instead of expelling it completely to make room for fresh air
//////////////////////Staurikosaurus ("Southern Cross lizard") is a genus of early dinosaur from the Late Triassic of Brazil.
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//////////////////PANGEA- FOOD CHAIN COLLAPSES
///////////////////Megazostrodon is an extinct Mammaliaform, widely accepted as being one of the first mammals, appearing in the fossil record approximately 200 million years ago.[1] It did have some non-mammalian characteristics[2] but they were minor enough to be able to say that this animal is likely to represent the final stage of the transition between cynodont, or "mammal-like" reptiles and true mammals#
///////////////WILSON SUPERCYCLE- supercontinent cycle describes the quasi-periodic aggregation and dispersal of Earth's continental crust. There are varying opinions as to whether Earth's budget of continental crust is increasing, decreasing, or remaining about constant, but it is agreed that this inventory is constantly being reconfigured. One complete Supercontinent cycle is said to take 300 to 500 million years to occur.
Continental collision makes fewer and larger continents while rifting makes more and smaller continents. The last supercontinent, Pangaea, formed about 300 million years ago. The previous supercontinent, Pannotia, formed about 600 million years ago, and its dispersal formed the fragments that ultimately collided to form Pangaea. But beyond this the time span between supercontinents becomes more irregular. For example, the supercontinent before Pannotia, Rodinia, existed ~1.1 billion to ~750 million years ago - a mere 150 million years before Pannotia. The supercontinent before this was Columbia: ~1.8 to 1.5 billion years ago. And before this was Kenorland: ~2.7 to ~2.1 billion years ago. The first supercontinents were Ur (existed ~3 billion years ago) and Vaalbara (~3.6 to ~2.8 billion years ago).
The hypothetical supercontinent cycle is, in some ways, the complement to the Wilson cycle. The latter is named after plate tectonics pioneer J. Tuzo Wilson and describes the periodic opening and closing of ocean basins. Because the oldest seafloor is only 170 million years old, whereas the oldest bit of continental crust goes back to 4 billion years or more, it makes sense to emphasize the much longer record of the planetary pulse that is recorded in the continents.--WIKI
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