- the theory of evolution as expounded by later students of Charles Darwin, especially Weismann, holding that natural selection accounts for evolution and denying the inheritance of acquired characters.
- any modern theory of evolution holding that species evolve by natural selection acting on genetic variation.
- the modern version of the Darwinian theory of evolution, which incorporates the principles of genetics to explain how inheritable variations can arise by mutation
- Darwinism as modified by the findings of modern genetics.
- Darwinism as modified by the findings of modern genetics, stating that mutations due to random copying errors in DNA cause variation within a population of individual organisms and that natural selection acts upon these variations.