Adaptations are the result of spontaneous mutations that happen to have some sort of beneficial effect for the mutated creature. Since this mutant has an advantage over the other "normal" forms of the species, it gets to have more babies, thus slowly taking over the gene pool. More and more of future generations of the species will contain the mutation, thanks to natural selection.
Not all mutations result in adaptations. An adaptation must:
- be functional toward a specific task; in other words, it must actually do something
- provide some benefit that allows the organism to better survive and reproduce in its environment
- be heritable (able to be passed on to the young 'uns)
Mutations that help a bug survive and reproduce are more likely to become adaptations of the species. Less helpful mutations will not last many generations. .
A bug with the "Rogue" mutation, on the other hand, would not be as fortunate. Although it's otherwise healthy and attractive, since it would suck the life out of any other bug it touched it's not likely that there would be many chances for successful mating.
Natural selection is one of the accepted mechanisms of evolution.
- Natural Selection
- Genetic drift
- Gene flow
Learn more about evolution from the University of California Museum of Paleontology