Sensitive and efficient 4. Genetic variation is raw material for evolution and adaptation. Evolution relates to structure, function, behavior of organsims and how they interact with each other. Only populations evolve, not individuals Best adapted organisms in a population, on average, leave more offspring than less well adapted organisms. We know now that different forms of genes give variations in characteristics.
Mutations lead to variation, raw material for evolution.
Certain tree trunks in England were white because of lichen growing on the trunks The common peppered moth was white, to blend into the lichen and avoid being seen by birds. Dark moths were rare. Pollution killed the lichen and blackened the tree trunks Light colored moths were visible and eaten. Dark moths survived. HBD Kettlewell, 1950's.