Speciation is the process by which new species form. It occurs when groups in a species become reproductively isolated and diverge. In allopatric speciation, groups from an ancestral population evolve into separate species due to a period of geographical separation.
Answer:
New species can appear gradually through small changes in an ancestral species.
Explanation:
The new species that appear are due to hereditary variations that occur in a population. The adaptive variations are said to confer a selective advantage to organisms possessing them. The result of variations is that well adapted individuals are able to survive and reach the reproductive age and pass over their favourable characteristics to their offspring.
<span>The nurse should tell the patient that eating a variety of healthy food is the best source of vitamins<span>. This is should be told by the nurse in a nice and emphatic manner, especially in this case wherein patients diagnosed with HIV are particularly emotionally sensitive. While this is true, the nurse should not advise the patient to stop taking his or her supplements; especially being diagnosed with HIV, his or her immune system is very frail and needs more than the usual nutrients compared to the normal population. </span></span>
<span>Facilitated diffusion
Diffusion
occurs because of the movement of molecules from the region of higher
concentration to the region of lower concentration. This movement of
molecules occurs due to a thermal motion. Diffusion normally occurs
between two compartments having difference in concentration. In case of
fluid it moves from the region of higher concentration to the region of
concentration until a balance is reached. The process of diffusion is
very important for the humans as well. The oxygen that humans breathe in
gets diffused with the blood.<span> </span></span>