The third mechanism of evolution

Since the early 1980s, Gabriel Dover has been one of the most 

Dover underlined that there is no rigid one-to-one relationship between evolutionary mechanisms and environmental processes, but noticed nonetheless that a certain correspondence does exist. He concluded therefore that adaptation is the normal result of natural selection just as exaptation is characteristic of neutral drift, and adoptation is typical of molecular drive. To our purposes, what matters is that we can indeed speak of three mechanisms of evolution the first two are natural selection and neutral drift, while the third mechanism can be called either genomic flux or molecular drive. 

Eldredge and Gould concluded that the history of species is not a uniform accumulation of small changes, but is made of long periods of stasis (the equilibria) which are occasionally interrupted by quick 

The question, at this point, was que faire When a widely accepted solution is found wanting, the need to replace it with an alternative model is strong, and Eldredge and Gould discovered that a way out is offered by the idea of species selection. If species are regarded as organic systems that are born, live and die as individuals do, one can conclude that a selection mechanism operates at the species level as it does at the individual level. 

This solution kills the proverbial two birds with one stone. On the one hand, it is acknowledged that microevolution and macroevolution are two separate hierarchical levels, and therefore that each of them has its own independent laws. On the other hand, 

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