The table below shows the fossils found in various layers of an undisturbed rock: Fossils In Rock Layers
Layer (from top) Fossils in Layer
1 A, C
2 E
3 A, D, F
4 B
5 F, C
6 D, B

Which is most likely an index fossil?
A
B
D
E

What kind of action is a cause of air pollution

Based on the data in your tables, did the light-colored moths have a higher or lower survival rate after the industrial revolution?

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.