How can turning off your lights when you’re not using them decrease air pollution

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.

What type of graph presents information about how often certain or traits occur?

Both destructive and constructive, the natural event seen here, is important in destroying and creating landforms on earth. what is this event called? a) deposition b) flooding c) landslide d) sedimentation