Microevolution vs Macroevolution - misconceptions
Much of the misconception of these concepts has to do with the definition of what consititues a species - and in fact this is somewhat arbitrary (much like defining/deliniating one race from another) etc
From above:
There is no difference between micro- and macroevolution except that genes between species usually diverge, while genes within species usually combine. The same processes that cause within-species evolution are responsible for above-species evolution, except that the processes that cause speciation include things that cannot happen to lesser groups, such as the evolution of different sexual apparatus (because, by definition, once organisms cannot interbreed, they are different species).
The idea that the origin of higher taxa, such as genera (canines versus felines, for example), requires something special is based on the misunderstanding of the way in which new phyla (lineages) arise. The two species that are the origin of canines and felines probably differed very little from their common ancestral species and each other. But once they were reproductively isolated from each other, they evolved more and more differences that they shared but the other lineages didn't. This is true of all lineages back to the first eukaryotic (nuclear) cell.
Much of the misconception of these concepts has to do with the definition of what consititues a species - and in fact this is somewhat arbitrary (much like defining/deliniating one race from another) etc
From above:
There is no difference between micro- and macroevolution except that genes between species usually diverge, while genes within species usually combine. The same processes that cause within-species evolution are responsible for above-species evolution, except that the processes that cause speciation include things that cannot happen to lesser groups, such as the evolution of different sexual apparatus (because, by definition, once organisms cannot interbreed, they are different species).
The idea that the origin of higher taxa, such as genera (canines versus felines, for example), requires something special is based on the misunderstanding of the way in which new phyla (lineages) arise. The two species that are the origin of canines and felines probably differed very little from their common ancestral species and each other. But once they were reproductively isolated from each other, they evolved more and more differences that they shared but the other lineages didn't. This is true of all lineages back to the first eukaryotic (nuclear) cell.
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