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Which of the following factors would not contribute to allopatric speciation? a) a population becomes geographically isolated from the parent population.b) the separated population is small, and genetic drift occurs.c) the isolated population is exposed to different selection pressures than the ancestral population.d) different mutations begin to distinguish the gene pools of the separated populations.e) gene flow between the two populations is extensive.

What is the membrane that sheath of schwann cell containing cytoplasm and nucleus that encloses myelin

How can we use spectral lines of light coming from the superclusters to identify which is receding from earth at the slowest rate.