Evolution has four principles:
- Inheritance
- Variation
- Selection
- Time
Inheritance refers to the ability of the individuals of the population to pass their genes to the next generation.
Variation refers to the differences in the genetic structure of the individuals of the population, which produces differences in their physical characteristics.
Selection refers to individuals that might inherit genes that give them a higher chance of surviving and passing their genes to the next generations.
Time refers to the fact that for any population to show the effects of evolution. This cannot be observed in one or two generations, for a new species to evolve, many generations are needed.