Answer:
A multi-component effect
Explanation:
In natural selection the organism is at the commiseration of the environment. This means that there are a certain amount of resources that are available for this individual. So, competition for food, a second type of pressure is in play. Competitions will cause the inevitable food shortage. Because of this animals may become sick and diseased and may not be able to overcome illnesses. Finally, predation becomes a factor on any population that is not on top of the food chain. Only the individuals of a population that is able to survive all these pressures will pass along the surviving traits to their offspring.
, and some die because of factors such as predation, food shortage or disease. ... Predation, competition and disease are examples of selection pressures.
