Principles of Natural Selection

From (edited):

Darwin's Theory of Natural Selection was based on four principles.

1. All species are capable of producing more than enough offspring to replace themselves. One pair of mice can produce a litter of abut six offspring as many as six times a year.

2. The environment may affect an individual's chances of survival. A mouse might be eaten by a predator before it could have offspring of its own.

3. Because individuals are not all identical, some may be more likely to survive than others. For instance, coat color varies among mice.

4. Against a dark background, the pale mice are easier to see, so they are the ones more likely to be eaten by owls. The dark mice are better adapted to this environment. Since coat color is inherited, the surviving mice will likely pass on dark coats to their decendents, thus, in this environment, mice with dark coats will be most prevalent.

Natural Selection

	1. All species are capable of producing more than enough offspring to replace themselves. One pair of mice can produce a litter of abut six offspring as many as six times a year.
	2. The environment may affect an individual's chances of survival. A mouse might be eaten by a predator before it could have offspring of its own.
	3. Because individuals are not all identical, some may be more likely to survive than others. For instance, coat color varies among mice.
	4. Against a dark background, the pale mice are easier to see, so they are the ones more likely to be eaten by owls. The dark mice are better adapted to this environment. Since coat color is inherited, the surviving mice will likely pass on dark coats to their decendents, thus, in this environment, mice with dark coats will be most prevalent.