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This page features a list of biogeographic provinces that were developed by Miklos Udvardy in 1975, [1] [2] later modified by other authors. [according to whom?] Biogeographic Province is a biotic subdivision of biogeographic realms subdivided into ecoregions, which are classified based on their biomes or habitat types and, on this page, correspond to the floristic kingdoms of botany.
[1]: 189 A classic example of habitat isolation occurring in allopatry is that of host-specific cospeciation [1]: 189 such as in the pocket gophers and their host chewing lice [24] or in the fig wasp-fig tree relationship and the yucca-yucca moth relationship—examples of ecological speciation caused by pollinator isolation.
Allopatric speciation (from Ancient Greek ἄλλος (állos) ' other ' and πατρίς (patrís) ' fatherland ') – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model [1]: 86 – is a mode of speciation that occurs when biological populations become geographically isolated from each other to an extent that prevents or interferes with ...
Over time, the isolation by distance model reveals a decline in local isolation and a rise in short and long range migration and the Sandy population experienced an isolate breakdown over time. Distance plays a role in determining kinship, but becomes less significant over time as the measures of the fit of the model decline.
Isolation index measures the degree to which people inhabit geographic units inhabited primarily by members of their own group. It is usually denoted by I. It is usually denoted by I. It varies from 0 to 1.0 and is defined as the proportion of own-group members in the unit of the average person.
The sexual isolation between Drosophila miranda and D. pseudoobscura, for example, is more or less pronounced according to the geographic origin of the flies being studied. Flies from regions where the distribution of the species is superimposed show a greater sexual isolation than exists between populations originating in distant regions.
The topographic isolation of a summit is the minimum horizontal distance to a point of equal elevation, representing a radius of dominance in which the peak is the highest point. It can be calculated for small hills and islands as well as for major mountain peaks and can even be calculated for submarine summits.
Servedio and Noor include any detected increase in prezygotic isolation as reinforcement, as long as it is a response to selection against mating between two different species. [4] Coyne and Orr contend that, "true reinforcement is restricted to cases in which isolation is enhanced between taxa that can still exchange genes". [3]: 352