Abnormalities in the number of x chromosomes tends to have milder phenotypic effects than the same abnormalities in autosomes because of
deletions
nonhomologous recombination
synapsis
x inactivation

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.