Supercontinent-Cycle Hypothesis
The supercontinent-cylce hypothesis is an addition to the Wilson cycle, which was proposed by J. Tuzo Wilson in the 1960's (Monroe, James). Unlike its predecessor, which stated that oceans basins simply opened and closed, the supercontinent-cycle hypothesis states that heat and pressure build up under supercontinents, causing these land masses to rise and form mountains. As these mountains grow, the heat underneath is unable to conduct through the rock material. Subsequently, a threshold is reached and the land cracks or breaks apart. Once fractured, the land masses drift away from each other and the narrow depression begins to fill up with sediments and water. This process, occurring over millions of years, forms oceans like the Atlantic. One of the most popular examples of this hypothesis is Pangea.
It is believed that the entire cycle from start to finish usually takes around 600 million years, and sometimes the subcontinents drift so far away from each other that they collide with other subcontentents to begin the process anew. The African continent is thought to be a modern example of this hypothesis because it has purportedly remained stationary, while other subcontenents routinely crash into it and then break off again over the course of hundreds of millions of years (KMT).
If this process were accurate, it would have dramatic effects on the environment. The animals would have to migrate into different parts of the continents due to shifting climates. As continents broke apart and ocean basins formed, numerous animals would be split off from each other. Over the vast amounts of time apart, the same species would begin to adapt to their individual ecosystems forming a variety of adaptations. With this hypothesis, forests would give way to arid deserts and deserts would be overgrown with lush, green vegetation again and again.
There are a number of difficulties with this hypothesis, though. One is the idea...
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