Z0000000000000000000000000000000000 00000000000000000000000000000000 in

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

New york city has 2,181 inhabitants per square mile. the state of alaska has 1.03 inhabitants per square mile. ecologists would say alaska has a low exponential growth population density birth rate carrying capacity

How do you date a sample of rock that you suspect as being one of the earliest on earth