Natural selection: the process by which organisms with variations most suited to their environment survive and leave more offspring.
The struggle for existence: Darwin read Malthus theory explaining that when members of a population become overcrowded they must compete for food and survival.
Variation and adaptation: Darwin configured that individuals have variations due to their heritable traits, so predators have physical traits like sharp teeth or claws to hunt prey and, prey are faster and camouflage.
Adaptation: any characteristic that helps and allows an organism to fully survive in an environment.
Survival of the fittest: Darwin realized that there was a connection between the way organisms make a living
Fitness: shows how well an organism can reproduce and survive in its natural environment.
Natural selection occurs in any type of situation in which there are more organisms born than needed so they have trouble surviving
Biogeography: the study of where organisms live now and in the past
Homologous structures:structures that are inherited from a common ancestor and are shed by closely related species. The Evolutionary theory explains that the existence of the homologous structures that adapted to purposes with the result of a modification from the original species.
Analogous structures: body parts in which share common function and not structure.
Vestigial structures: are inherited from ancestors but have lost almost all function due to different selection pressures acting on decent.