Natural selection, genetic drift, and common descent are all fundamental concepts in evolutionary biology that explain how organisms change over time.

Natural selection acts on heritable variations in a population, favoring individuals with traits that enhance their survival and reproductive success.

Adaptation refers to the process by which populations of organisms evolve traits that make them better suited to their environment, increasing their chances of survival and reproduction.

Camouflage, antibiotic resistance, and mimicry are all examples of adaptations that have evolved in organisms to enhance their survival and reproductive success.

Common descent is the fundamental concept in evolutionary biology that proposes that all living organisms have evolved from a common ancestor over time.

The fossil record, comparative anatomy, and molecular biology all provide evidence supporting the theory of common descent by demonstrating similarities among different organisms.

Speciation is the process by which populations of organisms diverge and become reproductively isolated from each other, leading to the formation of new species.

The evolution of different species of finches on the Galapagos Islands, wolves in North America, and humans in different parts of the world are all examples of speciation events.

Gradualism is the idea that evolution occurs through a slow and steady accumulation of changes over long periods of time.

The evolution of longer necks in giraffes is an example of a gradualistic evolutionary change, as it occurred over a long period of time through the accumulation of small changes.

Punctuated equilibrium is the idea that evolution occurs in sudden bursts of change followed by periods of stability, with long periods of stasis punctuated by relatively rapid bursts of evolutionary change.

The evolution of the horse is an example of a punctuated equilibrium evolutionary change, as it occurred in relatively rapid bursts followed by periods of stability.

Genetic drift is the idea that evolution can be driven by random changes in gene frequencies within a population, rather than by natural selection.

The evolution of antibiotic resistance in bacteria is an example of genetic drift, as it is driven by random changes in gene frequencies within a population.

Naturalism is the idea that evolution is a purposeless and meaningless process, driven by natural laws and devoid of any inherent purpose or direction.