Unlike cars, which are designed and built from technical blueprints filed in a safe place, each new generation of living organisms is constructed using internally coded, inheritable information. Often, the only tangible inheritance an offspring receives from its parents is the genetic information it needs to construct its body and live out its life.

Every living organism is the outward physical manifestation of internally coded, inheritable information.

Starting from a fertilized egg, a goldfish has all the genes necessary to construct and agile, water-dwelling creature capable of swimming. On the other hand, and eagle has all the genes necessary to construct and aerodynamic, air-breathing, feather-covered carnivore. Both organisms are well adapted to their environments.

Their adaptations fit them into their environments and increase their reproductive success.

For example, animals must protect themselves from becoming a predator's next meal. These defensive adaptations increase their reproductive success.

Darwin searched for a "mechanism" of evolution for many years and eventually published his evidence for the Origin of Species by Means of Natural Selection, in 1859. It was so comprehensive it swept away all other theories and became a major turning point in the study of biology.

The raw material for all evolutionary change is variation in the genes and hence the phenotypes of every individual organism.

There are sources in increased variation, and other forces working to decrease the amount of variation in any population of organisms.

Evolution is far from a theoretical science. It is possible to do experiments in natural selection, including antibiotic resistance in bacteria, fighting the tobacco budworm in agriculture, and the study of pollution and butterflies in England.