Did dinosaurs and humans exist at the same time? What is your evidence?

What would happen to the nutrients in an ecosystem if decomposers, such as bacteria, didn’t exist there?

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 is the cause hearing loss in human being