A variance is an exception to one or more of the zoning restrictions on a piece of property. A variance is different from a nonconforming use, which permits existing structures and uses to continue when zoning is first instituted.
The book, On The Origin Of Species,  suggested  that organisms evolve through the process of natural selection.opulations evolve as the individual organisms less able to survive in the current environment die and fail to reproduce. That is natural selection.
Pre-Darwinian ideas about evolution It was Darwin's genius both to show how all this evidence favored the evolution of species from a common ancestor and to offer a plausible mechanism by which life might evolve. Lamarck and others had promoted evolutionary theories, but in order to explain just how life changed, they depended on speculation.