What can you conclude about fossil by looking at the layers of rock? a. the exact age of the fossil b. the fossils in the lower layers are older than the fossils in the upper layers. c. there is no difference in age between the different layers of rock d. the fossils in the upper layers are the ancestors of the fossils in the lower layers.

What are the most explosive events that occur on the sun? umbras solar flares solar winds prominences

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?

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.