Heteropatric speciation
Encyclopedia
Heteropatric and heteropatry are terms from biogeography
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...

, referring to organism
Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...

s whose geographical ranges overlap or are even identical, so that they occur together at least in some places, but which occupy ecological niche
Ecological niche
In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; e.g. a dolphin could potentially be in another ecological niche from one that travels in a different pod if the members of these pods utilize significantly different food...

s distinct enough to prevent frequent hybridization. Such organisms are usually closely related (e.g. sister species), their distribution and ecology
Ecology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...

 being the result of heteropatric speciation.

Heteropatric speciation is a special case of sympatric speciation
Sympatric speciation
Sympatric speciation is the process through which new species evolve from a single ancestral species while inhabiting the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap or are even identical, so that...

 that occurs when different ecotypes or race
Race (biology)
In biology, races are distinct genetically divergent populations within the same species with relatively small morphological and genetic differences. The populations can be described as ecological races if they arise from adaptation to different local habitats or geographic races when they are...

s of the same species geographically coexist but exploit different niches in the same patchy or heterogeneous environment. Thus heteropatric speciation is a refinement of our notion of sympatric speciation
Sympatric speciation
Sympatric speciation is the process through which new species evolve from a single ancestral species while inhabiting the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap or are even identical, so that...

 in that it represents a behavioral rather than geographic barrier to the flow of genes among diverging groups within a population. The importance of behavioral separation as a mechanism for promoting sympatric speciation in a heterogeneous or patchwork landscape is highlighted in John Maynard Smith
John Maynard Smith
John Maynard Smith,His surname was Maynard Smith, not Smith, nor was it hyphenated. F.R.S. was a British theoretical evolutionary biologist and geneticist. Originally an aeronautical engineer during the Second World War, he took a second degree in genetics under the well-known biologist J.B.S....

's seminal paper on sympatric speciation
Speciation
Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages...

. In recognition of the importance of this behavioral versus geographic distinction, Wayne Getz and Veijo Kaitala introduced the term heteropatry in their extension of Maynard Smiths' analysis of conditions that facilitate sympatric speciation
Sympatric speciation
Sympatric speciation is the process through which new species evolve from a single ancestral species while inhabiting the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap or are even identical, so that...

.

Although some evolutionary biologists still regard sympatric speciation as a highly contentious issue, both theoretical and empirical studies increasingly support sympatric speciation as a likely process in explaining the diversity of life in particular ecosystems. Arguments either implicitly or explicitly implicate competition and niche separation of sympatrically co-occurring ecological variants that through assortative mating
Assortative mating
Assortative mating , and the related concept Disassortative mating, is the phenomenon where a sexually reproducing organism chooses to mate with individuals that are similar or dissimilar to itself in some specific manner...

 ultimately evolve into separate races and then species. Assortative mating most easily occurs if mating is linked to niche preference, as occurs in the apple maggot
Apple maggot
The apple maggot , also known as railroad worm, is a pest of several fruits, mainly apples. The adult form of this insect is about 5 mm long, slightly smaller than a house fly, with a white dot on its thorax and a characteristic black banding shaped like an "F" on its wings...

 Rhagoletis pomonella where individual flies from different races use volatile odors to discriminate between hawthorn and apple and look for mates on natal
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...

 fruit.

In essence, the term heteropatry semantically resolves the issue of sympatric speciation by reducing it to a scaling issue in terms of the way the landscape is used by individuals versus populations. Specifically, from a population perspective, the process looks sympatric, but from an individual’s perspective, the process looks allopatric, once the time spent flying over or moving quickly through intervening non-preferred niches is taken into account.

See also

  • Adaptive radiation
    Adaptive radiation
    In evolutionary biology, adaptive radiation is the evolution of ecological and phenotypic diversity within a rapidly multiplying lineage. Starting with a recent single ancestor, this process results in the speciation and phenotypic adaptation of an array of species exhibiting different...

  • Sympatry
    Sympatry
    In biology, two species or populations are considered sympatric when they exist in the same geographic area and thus regularly encounter one another. An initially-interbreeding population that splits into two or more distinct species sharing a common range exemplifies sympatric speciation...

  • Allopatry
  • Cladistics
    Cladistics
    Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

  • Phylogenetics
    Phylogenetics
    In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...

  • speciation
    Speciation
    Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages...

  • sympatric speciation
    Sympatric speciation
    Sympatric speciation is the process through which new species evolve from a single ancestral species while inhabiting the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap or are even identical, so that...

  • allopatric speciation
    Allopatric speciation
    Allopatric speciation or geographic speciation is speciation that occurs when biological populations of the same species become isolated due to geographical changes such as mountain building or social changes such as emigration...

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