A mutation is a change in the structure of a gene and a process that is fundamental to biodiversity and evolution. Mutations can result from errors in DNA replication during cell division, from exposure to mutagens (radiation or some chemicals) and from viral infections. A mutation acquired during an organism's lifetime can be passed to its offspring if occurs in germ-line cells (egg and sperm cells).
Most mutations are benign and have no noticeable effect on an organism, its offspring and its environment. Others, however, are harmful and can negatively affect an organism's quality of life, its longevity, its offspring, and/or other organisms in its habitat. Still others, but very rarely, are beneficial and will increase the possibility that an organism will thrive and pass on its mutated genes, and possible new characteristics, to subsequent generations.