selection pressure
Are environmental factors which may reduce reproductive success in a population and thus contribute to evolutionary change or extinction through the process of natural selection.
Examples:
· Competition
· Predation
· Disease
· Parasitism
· Land clearance
· Climate change
· Pollutants
An organism’s colour may affect its survival chances. For example, insects with colours that blend in to their surroundings are less likely to be seen by predators such as birds. A mutation that produces coloration similar to an insect’s usual background, for example, a green colour in a species that spends most of its time eating the leaves of plants, will increase its chances of successful reproduction, and over a number of generations, this will become the normal form. Mutations that produce a different colour will quickly disappear from the population.
Examples:
· Competition
· Predation
· Disease
· Parasitism
· Land clearance
· Climate change
· Pollutants
An organism’s colour may affect its survival chances. For example, insects with colours that blend in to their surroundings are less likely to be seen by predators such as birds. A mutation that produces coloration similar to an insect’s usual background, for example, a green colour in a species that spends most of its time eating the leaves of plants, will increase its chances of successful reproduction, and over a number of generations, this will become the normal form. Mutations that produce a different colour will quickly disappear from the population.