Kin selection is a process whereby natural selection favours a trait due to its positive effects on the reproductive success of an organism's relatives, even when at a cost to the organism's own survival and reproduction. Kin selection can lead to the evolution of altruistic behaviour. Kin selection is related to the concept of inclusive fitness, which combines the number of offspring produced with the number an individual can ensure the production of by supporting others. A broader definition of kin selection includes selection acting on interactions between individuals who share a gene of interest even if the gene is not shared due to common ancestry.
Small populations can behave differently from larger populations. They are often the result of population bottlenecks from larger populations, leading to loss of heterozygosity and reduced genetic diversity and loss or fixation of alleles and shifts in allele frequencies. A small population is then more susceptible to demographic and genetic stochastic events, which can impact the long-term survival of the population. Therefore, small populations are often considered at risk of endangerment or extinction, and are often of conservation concern.
In anthropology, kinship is the web of social relationships that form an important part of the lives of all humans in all societies, although its exact meanings even within this discipline are often debated. Anthropologist Robin Fox says that the study of kinship is the study of what humans do with these basic facts of life – mating, gestation, parenthood, socialization, siblingship etc. Human society is unique, he argues, in that we are "working with the same raw material as exists in the animal world, but [we] can conceptualize and categorize it to serve social ends." These social ends include the socialization of children and the formation of basic economic, political and religious groups.
The Sokoke is natural breed of domestic cat, developed and standardised, beginning in the late 1970s, from the feral khadzonzo landrace of eastern, coastal Kenya. The Sokoke is recognized by four major cat pedigree registry organizations as a standardised cat breed. It is named after the Arabuko Sokoke National Forest, the environment from which the foundation stock was obtained, for breed development primarily in Denmark and the United States. The cat is long-legged, with short, coarse hair, and typically a tabby coat, though specific lineages have produced different appearances. Although once rumored to be a domestic × wildcat hybrid, genetic study has not borne out this belief. Another idea, that the variety is unusually ancient, remains unproven either way. The native population is closely related to an island-dwelling group, the Lamu cat, further north.
In biology and genetic genealogy, the most recent common ancestor (MRCA), also known as the last common ancestor (LCA) or concestor, of a set of organisms is the most recent individual from which all the organisms of the set are descended. The term is also used in reference to the ancestry of groups of genes (haplotypes) rather than organisms.
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological processes that slowly alter the layout of the physical environment, and human activity such as land conversion, which can alter the environment much faster and causes the extinction of many species. More specifically, habitat fragmentation is a process by which large and contiguous habitats get divided into smaller, isolated patches of habitats.
A genetic marker is a gene or DNA sequence with a known location on a chromosome that can be used to identify individuals or species. It can be described as a variation that can be observed. A genetic marker may be a short DNA sequence, such as a sequence surrounding a single base-pair change, or a long one, like minisatellites.
Spatial ecology studies the ultimate distributional or spatial unit occupied by a species. In a particular habitat shared by several species, each of the species is usually confined to its own microhabitat or spatial niche because two species in the same general territory cannot usually occupy the same ecological niche for any significant length of time.
A genealogical DNA test is a DNA-based genetic test used in genetic genealogy that looks at specific locations of a person's genome in order to find or verify ancestral genealogical relationships, or to estimate the ethnic mixture of an individual. Since different testing companies use different ethnic reference groups and different matching algorithms, ethnicity estimates for an individual vary between tests, sometimes dramatically.
Limenitis arthemis, the red-spotted purple or white admiral, is a North American butterfly species in the cosmopolitan genus Limenitis. It has been studied for its evolution of mimicry, and for the several stable hybrid wing patterns within this nominal species; it is one of the most dramatic examples of hybridization between non-mimetic and mimetic populations.
Human genetic variation is the genetic differences in and among populations. There may be multiple variants of any given gene in the human population (alleles), a situation called polymorphism.
Theridion grallator, also known as the Hawaiian happy-face spider, is a spider in the family Theridiidae that resides on the Hawaiian Islands. T. grallator gets its vernacular name of "Hawaiian happy-face spider" from the unique patterns superimposed on its abdomen, specifically those that resemble a human smiling face. T. grallator is particularly notable because of its wide range of polymorphisms that may be studied to allow a better understanding of evolutionary mechanisms. In addition to the variety of color polymorphisms present, T. grallator demonstrates the interesting quality of diet-induced color change, in which its appearance temporarily changes as it metabolizes various food items.
In biology, a cline is a measurable gradient in a single characteristic of a species across its geographical range. First coined by Julian Huxley in 1938, the cline usually has a genetic, or phenotypic character. Clines can show smooth, continuous gradation in a character, or they may show more abrupt changes in the trait from one geographic region to the next.
Apis dorsata, the rock bee or giant honey bee, is a honey bee of South and Southeast Asia. They are typically around 17–20 mm (0.7–0.8 in) long and nests are mainly built in exposed places far off the ground, like on tree limbs, under cliff overhangs, and under buildings. These social bees are known for their aggressive defense strategies and vicious behavior when disturbed. Though not domesticated, indigenous peoples have traditionally used this species as a source of honey and beeswax, a practice known as honey hunting.
In biology, evolution is the process of change in all forms of life over generations, and evolutionary biology is the study of how evolution occurs. Biological populations evolve through genetic changes that correspond to changes in the organisms' observable traits. Genetic changes include mutations, which are caused by damage or replication errors in organisms' DNA. As the genetic variation of a population drifts randomly over generations, natural selection gradually leads traits to become more or less common based on the relative reproductive success of organisms with those traits.
Bombus affinis, commonly known as the rusty patched bumble bee, is a species of bumblebee endemic to North America. Its historical range in North America has been throughout the east and upper Midwest of the United States, north to Ontario, Canada, where it is considered a "species at risk", east to Quebec, south to Georgia, and west to the Dakotas. Its numbers have declined in 87% of its historical habitat range. On January 10, 2017, the United States Fish and Wildlife Service placed B. affinis on the list of endangered species, making the rusty patched bumblebee the first bee to be added to the list in the continental United States.
Inclusive fitness in humans is the application of inclusive fitness theory to human social behaviour, relationships and cooperation.
This glossary of evolutionary biology is a list of definitions of terms and concepts used in the study of evolutionary biology, population biology, speciation, and phylogenetics, as well as sub-disciplines and related fields. For additional terms from related glossaries, see Glossary of genetics, Glossary of ecology, and Glossary of biology.
Human genetic clustering refers to patterns of relative genetic similarity among human individuals and populations, as well as the wide range of scientific and statistical methods used to study this aspect of human genetic variation.
This glossary of genetics is a list of definitions of terms and concepts commonly used in the study of genetics and related disciplines in biology, including molecular biology, cell biology, and evolutionary biology. It is split across two articles:
