Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Parapatry


Related Topics

In the News (Sat 20 Apr 19)

  
  Amazon.com: Parapatry
of cetacean populations in sympatry, parapatry, and mixed assemblages: Implications for...
cetacean populations in sym- patry, parapatry, and mixed assemblages: implications for...
On the parapatry of Malaclennls: A molecu- lar...
www.amazon.com /s?ie=UTF8&keywords=Parapatry&index=blended&page=1   (789 words)

  
  Parapatry Article, Parapatry Information
Parapatry is a type of speciation in the theory of natural selection.
The concept of parapatry is necessary to satify the postulate of natural selection that two speciescannot co-exist in the same location over the longer term with the same ecological niche.
Parapatry is relatively uncommon in temperate areas, but can be seen more often in tropical areas.
www.anoca.org /species/two/parapatry.html   (238 words)

  
 CiteULike: Accumulating postzygotic isolation genes in parapatry: a new twist on chromosomal speciation.   (Site not responding. Last check: )
Accumulating postzygotic isolation genes in parapatry: a new twist on chromosomal speciation.
We model the effects of the genetic barrier to gene flow caused by a chromosomal rearrangement on the rate of accumulation of postzygotic isolation genes in parapatry.
We find that, if reproductive isolation is produced by the accumulation in parapatry of sets of alleles compatible within but incompatible across species, chromosomal rearrangements are far more likely to favor it than classical genetic barriers without chromosomal changes.
www.citeulike.org /user/stevanspringer/article/524849   (347 words)

  
  Dispersal Can Sharpen Parapatric Boundaries On A Spatially Varying Environment Ecology - Find Articles
Parapatry describes a geographic pattern in which the ranges of two species have separate but contiguous distributions without any physical barriers between them.
Parapatry occurred under several conditions, including when both species were identical in dispersal, intrinsic rate of growth, and competition but differed in their spatial performances.
Parapatry is the geographic pattern that is assumed to result from parapatric speciation, allopatric speciation with secondary contact, or peripheral isolated speciation (White 1973, Bush 1975, Endler 1977, Lynch 1989).
findarticles.com /p/articles/mi_m2120/is_3_81/ai_61242203?lstpn=article_results&lstpc=search&lstpr=external&lstprs=other&lstwid=1&lstwn=search_results&lstwp=body_middle   (815 words)

  
 NationMaster - Encyclopedia: Allopatric speciation   (Site not responding. Last check: )
Proponents of peripatric speciation contend that small population size in the peripheral isolate allows genetic drift, which can be a more powerful force than natural selection in small populations, to deconstruct complex genotypes, allowing the creation of novel gene combinations.
Peripatric speciation (also known as Parapatry) is a type of speciation in the theory of natural selection.
Species with a small population size are subject to a higher chance of extinction because their small population size makes them more vulnerable to genetic drift, resulting in stochastic variation in their gene pool, their demography and their environment.
www.nationmaster.com /encyclopedia/Allopatric-speciation   (868 words)

  
 Species
The dividing line is often a sudden change in habitat (an ecotone[?]) like the edge of a forest or the snow line on a mountain, but can sometimes be remarkably trivial.
The parapatry itself indicates that the two populations occupy such similar ecological roles that they cannot coexist in the same area.
Because they do not crossbreed, it is safe to assume that there is a mechanism, often behavioral, that is preventing gene flow between the populations, and therefore that they should be classified as separate species.
www.fastload.org /sp/Species.html   (3077 words)

  
 The Mathematical Institute Eprints Archive - Dispersal can sharpen parapatric boundaries on a spatially varying ...
Parapatry describes a geographic pattern in which the ranges of two species have separate but contiguous distributions without any physical barriers between them.
Parapatry occurred under several conditions, including when both species were identical in dispersal, intrinsic rate of growth, and competition but differed in their spatial performances.
Results indicate that overlapping distributions and parapatry are equally expected for close species.
eprints.maths.ox.ac.uk /428   (325 words)

  
 timema
This pattern indicates that gene flow in parapatry constrains divergence.
An exception to this pattern occurs for sexual isolation, where divergence mate preferences have been reinforced in parapatry in response to selection against hybrids.
Rearing experiments have show that reproductive isolation has a genetic basis such that both ecology and geography affect progress towards speciation.
www.sfu.ca /~pnosila/timema.html   (1150 words)

  
 BIOL B242 - EVOLUTION IN SPACE AND TIME
Because all intermediates between slight genetic differentiation and separate species occur in parapatry, we can use these examples to study the time course of speciation.
Disruptive selection of this kind isalso implicated in models of sympatric speciation (a couple of lectures from now), but it clearly could be important for generating divergence in parapatry.
Another and very important potential example of epistatic/disruptive selection is sexual selection and mating behaviour, in which genes for mate choice are strongly epistatic on genes for the traits being chosen.
www.ucl.ac.uk /~ucbhdjm/courses/b242/Hz/Hz.html   (2884 words)

  
 Inferring the Mode of Speciation From Genomic Data: A Study of the Great Apes -- Osada and Wu 169 (1): 259 -- Genetics
is 50% larger in parapatry than in allopatry,
paradoxical result is that, under parapatry, the estimate of
be seen as a hybrid between parapatry and allopatry.
www.genetics.org /cgi/content/full/169/1/259   (2851 words)

  
 NEWS TASMANIA TASMANIAN TOURISM FORESTRY - JANUARY 2005
Its habitat of rotting logs and moist environment will be destroyed from logging and the subsequent burning of the coupe.
The Giant Velvet Worm, is found adjacent to the coupe with the line of parapatry (geographical line separating the two species) running through the coupe.
Wedge tail eagles are seen daily flying around this area, Swift parrots have been recently confirmed on the coupe and Grey Goshawks are often seen flying in the general vicinity.
www.news-tasmania.com /january-05.html   (2677 words)

  
 blog.talkingphilosophy.com » Dawkins, Fred Hoyle and ‘The Evolution Delusion’
The defenders of evolution complain that whilst Dick Dawkins’s arguments are well-put, he’s criticising a version of evolutionary theory that sophisticated believers in evolution don’t accept anyway.
He doesn’t mention natural selection, for example; he ignores allopatry and parapatry as explanations of speciation; he underplays the extent to which the fossil record supports common descent; and so on.
It looks like both sides are relying on the fossil record as their hard, empirical evidence for their respective views.
blog.talkingphilosophy.com /?p=21   (13906 words)

  
 BIOONE Online Journals - BIOONE Online Journals Access Control
Chromosomal rearrangements can promote reproductive isolation by reducing recombination along a large section of the genome.
We model the effects of the genetic barrier to gene flow caused by a chromosomal rearrangement on the rate of accumulation of postzygotic isolation genes in parapatry.
We find that, if reproductive isolation is produced by the accumulation in parapatry of sets of alleles compatible within but incompatible across species, chromosomal rearrangements are far more likely to favor it than classical genetic barriers without chromosomal changes.
www.bioone.org /bioone/?request=get-document&issn=0014-3820&volume=57&page=447   (316 words)

  
 Abstracts
The most likely mechanism is that shifts to ecologically different ants could lead to diversification if ants contributed to the integrity of the association or if divergence in ant preference had a pleiotropic affect on reproductive isolation.
If either were the case, it may be possible for diversification to occur in sympatry or at least in parapatry.
We used a comparative approach to test this idea in a phylogeny of the highly ant-associated genus,
people.su.se /~cpena/I_ELEN/abstracts.html   (7121 words)

  
 Evidence for gene flow between wild and cultivated Medicago sativa (Leguminosae)based on allozyme markers ...
not necessarily restricted to narrow zones of close parapatry,
roadsides and fields and grow in parapatry with cultivated plants
integrity in wild populations despite their parapatry with cultivated
www.amjbot.org /cgi/content/full/86/5/677   (4712 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.