Artificial selection

Artificial selection is the process by which plants or animals kept by breeders are gradually improved. Minor variations in the organisms occur and perceptive breeders notice them and breed only from those organisms which show desired variations. Over time, these variations accumulate and significant changes can be made to the stocks.

Natural Selection

Natural selection is the process by which plants and animals in nature are gradually improved and adapted to their environment. As all organisms are engaged in a constant struggle for existence, those organisms that exhibit variations which increase their chances of survival will tend to survive and reproduce more than those against which they compete. As a result, natural selection will accumulate these helpful variations and, over time, great changes can occur. Darwin believes that natural selection is the means by which one species descends from another.

Geological Record

The geological record is...