Why do you think the winter layers are darker than the summer layers in the ice core? Screen shot is included

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere,b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify,d)anaerobic bacteria kept thriving with more oxygen

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.

Ts assignment - snow day assignment genetic variation and natural selection natural selection relies on genetic variation. in any population of beetles, there are alleles for brown or green color. what happens to the genotype and the phenotype of the beetle population when there are distinct advantages and disadvantages due to color? order the steps that take place during natural selection in this beetle population.