In a study comparing the genetic contribution to eating disorders, researchers found that in ___% of identical twin pairs both twins had bulimia nervosa, while that number was ___% of fraternal twin pairs. Although this does not rule out the influence of environmental and sociocultural factors, it does present compelling evidence for a genetic contribution to these conditions.

Acommon kind of mechanical weathering is called

Moving down the ramp from 6 meters to

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.