The evolution of larks shows that heredity and variation are common in nature. Without heritable variation, it is impossible to produce new organisms.

Heredity and variation are the basic characteristics of living things. Genetic stability is the basis of biological survival and species stability, maintaining the continuity of species. Biological reproduction does not simply copy itself, but produces a new life different from its parents, and variation increases the diversity within the species.

In the process of reproduction, individuals are different in many traits, such as size, beak shape, feeding habits and so on. Many of them are heritable. The beak of the American finch has not changed to adapt to the environment. Organisms tend to overproduce. In the process of survival, living things should fight for survival in order to get enough food and living space. In the competition for survival, individuals with favorable variation are easy to survive, that is, the survival of the fittest. Individuals with unfavorable mutation will die, that is, those who are not suitable will be eliminated. After many generations of selection and accumulation, many new varieties will be formed. Therefore, the evolution of American finches shows that there are genetic and variation phenomena in nature. If there is no heritable variation, there will be no genetic variation. It is possible to produce new biological types. Therefore, the statement of the title is correct.

So the answer is: √.