"Natural selection is the differential survival and reproduction of individuals due to differences in phenotype."
The process by which organisms that are better adapted to their environment tend to survive and reproduce more offspring.
Genetic variation: This refers to the differences in the DNA sequences among individuals within a population.
Adaptation: This refers to the characteristic or trait that an organism possesses that enhances its survival and reproduction in a particular environment.
Selective pressure: These are the survival pressures that drive natural selection by favoring certain traits over others.
Survival of the fittest: This is the idea that individuals with the best adaptive traits will survive and reproduce, passing their advantageous traits on to the next generation.
Fitness: This refers to an individual's ability to survive and reproduce compared to others in its population.
Gene flow: This is the movement of genetic material from one population to another, which can affect genetic variation and evolution.
Speciation: This occurs when a population splits into two or more distinct, reproductively isolated groups that evolve to become different species.
Phylogenetics: This is the study of the evolutionary relationships among species based on shared ancestry and genetic similarity.
Convergent evolution: This occurs when two unrelated species evolve similar traits in response to similar environmental pressures.
Coevolution: This occurs when two or more species evolve in response to each other, often leading to a close relationship such as in pollination or predator-prey interactions.
Sexual selection: This is a type of natural selection where individuals with certain traits are more likely to mate, leading to the evolution of elaborate courtship displays or physical characteristics.
Cultural evolution: This refers to the transmission and evolution of behaviors and ideas through social learning and imitation.
Human evolution: This is the study of the evolution of humans and our close relatives, including our physical and behavioral adaptations over time.
Microevolution: This is the study of changes in genetic traits within a population over time, such as the evolution of antibiotic resistance in bacteria.
Macroevolution: This is the study of large-scale evolutionary patterns and processes, such as the origin and diversification of major groups of organisms.
Directional selection: This refers to the process whereby one phenotype becomes more common in a population due to the selective pressure acting on it. This may occur for example if a particular trait provides an advantage in a particular environment, such as long necks in giraffes who have to reach high up for leaves.
Disruptive selection: This occurs when two or more phenotypes are favored over an intermediate phenotype. This can occur in instances where different environments are present, or when there are contrasting strategies for survival, like the different beak sizes of finches in the Galapagos.
Stabilizing selection: This occurs when the extreme forms of a trait are selected against and the average or intermediate form is selected for. This is seen in human birth weight, where the average is the most favorable and deviations on either side can be harmful.
Sexual selection: This refers to selection that operates on traits that affect the ability of individuals to attract and mate with members of the opposite sex. Examples of these traits are bright feathers in birds and antlers in deer.
Kin selection: This is a type of evolution that favors the reproductive success of an individual's relatives, over the individual's direct reproductive success. This occurs when organisms that exhibit altruistic behavior towards their family members are selected for.
Artificial selection: This is the intentional selective breeding of plants or animals by humans for desired traits, such as increased crop yield or the appearance of certain traits in pets.
Natural selection: This is the primary driver of evolution, whereby individuals with traits that provide advantages in a given environment are more likely to survive and reproduce. This process can lead to the emergence of new species over time.
Group selection: This is the idea that natural selection can operate on a group of individuals, rather than just on individuals within the group. Such selection can be seen in social insects like ants, bees, and termites where individuals work together to increase the fitness of the group as a whole.
Coevolution: This is the process whereby two or more species evolve in response to each other over a long period of time. Examples are predator-prey relationships or the relationships between pollinators and the plants they pollinate.
Molecular evolution: This is the process of evolution at the molecular level, involving changes in DNA sequence, protein structure and function across generations.
"It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations."
"Charles Darwin popularised the term 'natural selection', contrasting it with artificial selection, which is intentional, whereas natural selection is not."
"Variation exists within all populations of organisms. This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations."
"Throughout the lives of the individuals, their genomes interact with their environments to cause variations in traits."
"Other factors affecting reproductive success include sexual selection (now often included in natural selection) and fecundity selection."
"Natural selection acts on the phenotype, the characteristics of the organism which actually interact with the environment."
"The genetic (heritable) basis of any phenotype that gives that phenotype a reproductive advantage may become more common in a population."
"Over time this process can result in populations that specialise for particular ecological niches (microevolution)."
"[Natural selection] may eventually result in speciation (the emergence of new species, macroevolution)."
"Natural selection is a cornerstone of modern biology."
"The concept, published by Darwin and Alfred Russel Wallace in a joint presentation of papers in 1858."
"He described natural selection as analogous to artificial selection, a process by which animals and plants with traits considered desirable by human breeders are systematically favored for reproduction."
"The concept of natural selection originally developed in the absence of a valid theory of heredity; at the time of Darwin's writing, science had yet to develop modern theories of genetics."
"The union of traditional Darwinian evolution with subsequent discoveries in classical genetics formed the modern synthesis of the mid-20th century."
"The addition of molecular genetics has led to evolutionary developmental biology, which explains evolution at the molecular level."
"While genotypes can slowly change by random genetic drift, natural selection remains the primary explanation for adaptive evolution."
"...Darwin's influential 1859 book On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life."
"Natural selection is the differential survival and reproduction of individuals due to differences in phenotype, contrasting it with artificial selection, which is intentional."
"Variation exists within all populations of organisms. This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations."