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Topic: Sympatry

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In the News (Sat 20 Apr 19)

  Integrity in the midst of sympatry: does sexual incompatibility facilitate the coexistence of metamorphic and ...   (Site not responding. Last check: 2007-10-06)
Integrity in the midst of sympatry: does sexual incompatibility facilitate the coexistence of metamorphic and paedomorphic mole salamanders (Ambystoma talpoideum)?
The integrity of genetically determined morphs of the same species in sympatry may be facilitated by sexual incompatibility (and thus reduced gene flow) between morphs.
We suggest that differences in the phenology of breeding are of greater significance in the maintenance of discrete morphs of the mole salamander in sympatry.
www.uga.edu /srel/Reprint/2660.htm   (283 words)

 Sympatry   (Site not responding. Last check: 2007-10-06)
on reinforcement, the authors began by establishing that the two species do indeed overlap in part of their range (a condition called sympatry), in central...
Sympatry is one of three theoretical models for the phenomenon of speciation.
Essentially, in direct contrast to allopatry, species undergoing sympatric speciation are not geographically isolated by, for example, a mountain or a river.
publicliterature.org /en/wikipedia/s/sy/sympatry.html   (173 words)

The isolated populations are then liable to diverge evolutionarily over many generations as a) they become subjected to dissimilar selective pressures and b) they independently undergo genetic drift; particularly when one of the subpopulations is small[?], a scenario that leads to the "founder's effect").
Another proposed mechanism of speciation is sympatry, by which new species emerge alonside the old.
This might occur if subpopulations became dependent on different plants within the same area, and if variations in mating led one subpopulation to become isolated reproductively from the other.
www.ebroadcast.com.au /lookup/encyclopedia/sy/Sympatry.html   (295 words)

 Sympatric speciation - Wikipedia, the free encyclopedia
In complete contrast to allopatry, species undergoing sympatric speciation are not geographically isolated by, for example, a mountain or a river.
By 1980 the theory was largely unfavourable given the void of empirical evidence available, and more critically the required conditions which scientists expect.
Ernst Mayr, one of the foremost thinkers on evolution, completely rejected sympatry outright, ushering in a climate of hostility towards the theory.
en.wikipedia.org /wiki/Sympatry   (395 words)

 [No title]
Zones of sympatry offer excellent opportunities for studying the role of natural selection in shaping vegetative and flower traits.
Preliminary molecular data (AFLPs) indicate that introgression in sympatric populations is not frequent, suggesting that fitness benefits in sympatry arose from species co-occurrence, and not primarily from transgressive character expression in hybrids.
In order to better understand the evolutionary forces affecting flower traits in sympatry, we are currently conducting large-scale field studies of wild populations supported by common garden plots and transplants, and first results of these experiments will be presented.
www.zbi.ee /Est2004/COZZOLINO.doc   (340 words)

 RedOrbit - Science - Habitat Shift of a Native Darter Etheostoma Olmstedi (Teleostei: Percidae) in Sympatry With a ...
Habitat Shift of a Native Darter Etheostoma Olmstedi (Teleostei: Percidae) in Sympatry With a Non-Native Darter Etheostoma Zonale
Sympatry and allopatry with Etheostoma zonale.-Etheostoma olmstedi shifted its habitat in the presence of E. onale.
The percent decrease in niche width from populations in sympatry to populations in allopatry with E. onale are given
www.redorbit.com /news/display?id=187732&source=r_science   (4324 words)

 BBS - Results - USGS Patuxent Wildlife Research Center
Given their almost total sympatry, none of the BBS data could be retroactively assigned to either species within the BBS database.
An unidentified flicker category also exists (AOU number 04123), and is used in the large region of sympatry between Yellow-shafted and Red-shafted flickers on the Great Plains and the much smaller region of sympatry between Gilded and Red-shafted Flickers in the southwestern U.S. BBS data from regions of sympatry should be viewed with considerable caution.
Given this uncertainty, data from the states and province where sympatry occurs should be used cautiously in the estimation of BBS population trends for these towhees, because some routes will only have identifications to species after 1995.
www.pwrc.usgs.gov /bbs/bbsnews/AOUsplt1.htm   (5377 words)

 Ask the Expert
Sympatry is a small contract consultancy specialising in applying the latest development in artificial intelligence.
It is not a general purpose software house, but where a larger development effort is needed Sympatry will build a team suitable for the project.
Sympatry has experience in AI applied to areas such as manufacturing cost control, route planning and financial modelling.
homepage.mac.com /nwalton/expert.htm   (196 words)

 APS Northeastern Division Abstracts
The North American pathosystem is characterized by sympatry of telial and aecial hosts (poplar and larch), where the rust completes its life cycle, and allopatry, where only the telial host is found.
To test the hypothesis that epidemics originate from sympatry, populations in sympatry and allopatry were surveyed in 1997 and 1998 using two Polymerase Chain Reaction - Single-Strand Conformational Polymorphism markers.
For both years, more alleles were found in sympatry than in allopatry, and most alleles found in allopatry were also present in sympatry.
www.apsnet.org /meetings/div/ne02abs.asp   (5322 words)

 About Us
Sympatry believes that computers are merely a tool to achive an end, and that to focus upon the computer as a direct replacement for what is currently possible is a mistake.
Perhaps you are merely inquistive and would like to know more about the prospective benefits to your business, in which case a workshop style presentation followed by a small scale pilot project would suffice.
Sympatry grew out of work done in the City of London on applying artificial intelligence to the financial markets, especially for real time trade opportunity identification and portfolio management.
homepage.mac.com /nwalton/aboutus.htm   (206 words)

 Black Duck -- Mallard Hybridization: Is it the Cause of the Declining Black Duck Population
If one looks at the human incursions that have occurred in the Chesapeake Bay region over the last century, then habitat loss due to man-induced urbanization practices of housing construction and road building at the expense of agricultural would have certainly exacerbated the habitat decline.
Sympatry can occur without interbreeding as long as extrinsic isolating barriers exist.
If hybridization were the cause then hunters should by harvesting increasing number of hybrids and their indication to this author is that this is not happening.
www.pc.cc.va.us /patterson/report.html   (2048 words)

 Intelligent Design the Future: Sympatry and Neo-Darwinism
Whether sympatry really occurs has been hotly debated in the evolutionary community for many years.
Studies of fish that appear to have speciated despite living together in the same lake and birds that are developing “races” because their young are raised hearing different calls and songs are two of the stories that are lending credence to sympatry among evolutionary biologists.
To hear Ken Miller or Barbara Forest tell it, one would think that research like that above would never be allowed in a world that accepted design as a live possibility (see here and here for discussions of their respective doomsday prophecies).
www.idthefuture.com /2006/03/sympatry_and_neodarwinism.html   (542 words)

 RedOrbit - Science - Habitat Shift of a Native Darter Etheostoma Olmstedi (Teleostei: Percidae) in Sympatry With a ...   (Site not responding. Last check: 2007-10-06)
Etheostoma zonale, the banded darter, was introduced to the Susquehanna River basin of Pennsylvania through an interbasin transfer, or transplantation of native fishes outside their natural range.
A substantial compression of niche width for all variables was observed from E. olmstedi populations in Nescopeck and Jack's creeks compared to Sugar Creek populations in high and low flows.
This shift in habitat use from allopatry to sympatry was accompanied by a compression of the realized niche.
www.redorbit.com /news/display?id=187732&source=r_science   (4324 words)

 The Talk.Origins Archive Post of the Month: June 2006 (via CobWeb/3.1 planetlab2.cs.unc.edu)   (Site not responding. Last check: 2007-10-06)
Although reproductive infertility or isolation is not something that selection "aims for", it is often a byproduct of changes made to the developmental cycle of the isolate population.
So, when the two get back in sympatry, they either can't interbreed (are isolated) or they can but the hybrids are not as fit as either of the parental variants (lowered hybrid fitness), and so they are then subjected to "reinforcing selection" to maintain isolation.
In this case a population of, say, flowering plants, is able to cross with some other species, but the progeny aren't thereby members of a new species, but backbreed into the population, changing its genetic constitution and adaptive niche so that when it is in sympatry with the original species, the population is now isolated.
www.talkorigins.org.cob-web.org:8888 /origins/postmonth/jun06.html   (856 words)

 The Scientist : Speciation's Defining Moment
The multifaceted debate bristles with any number of sharply contested points, but one that has provoked the greatest polarization is the concept of reinforcement.
Allopatry and sympatry, the two pillars of speciation, are separated by matters of geography.
Allopatric speciation, favored by Mayr, occurs when a species' range is split by some accident of nature, such as a volcanic eruption, an ice age, or a forest fire.
www.the-scientist.com /2005/4/11/30/1   (1459 words)

 Pasano B   (Site not responding. Last check: 2007-10-06)
Although currently listed as members of the same species, there is a growing belief that they may in fact represent two distinct species.
In western Kentucky where both occur, they have been described by some as intergrading, and by others as living in sympatry.
Although we are still in the process of collecting more samples, the data so far gives no indication of gene flow, and supports the second hypothesis that these two subspecies in western Kentucky are living in sympatry and acting as two true species.
campus.murraystate.edu /services/Ursa/web2/JaninePerkins.htm   (207 words)

In this way the Laysan and the Blackfoot came into near sympatry; the colonies were contiguous perhaps but not overlapping.
The 5- and 6-year-old juveniles do return to congregate and to socialize within a colony of their own kind rather than on its edges, and these mate-seeking birds are, therefore, most often in contact with conspecific albatrosses.
The purpose of this discussion is to present some views of the origin and subsequent sympatry of the Laysan and Black-footed albatrosses over virtually all their breeding range.
elibrary.unm.edu /sora/Auk/v089n02/p0381-p0402.html   (11332 words)

 genus aspidites peters womas and black headed pythons
Worrell (1963) recorded sympatry between both species in the Northern Territory.
To date no similar sympatry has been recorded in Queensland.
That sympatry occurs between the two species of Aspidites is not altogether surprising as their habitat preferences are somewhat generalist, with the snakes being found in a variety of habitat, soil and vegetation types.
www.smuggled.com /pr8.htm   (588 words)

 Comparison of dietary overlap between allopatric and sympatric geckos   (Site not responding. Last check: 2007-10-06)
This has resulted in a distribution in which the two populations’ are largely allopatric except for a narrow band of sympatry at the periphery of each of their ranges.
We examined stomach contents of both species in allopatry and sympatry in order to determine if dietary overlap in sympatry is less than that in allopatry.
In addition, we compared overlap between allopatric and sympatric populations within each species and found that the differences in resource utilization between the two species in sympatry was due to a dietary shift exhibited in H.
www.srs.fs.usda.gov /pubs/21074   (550 words)

 NESCent / Faculty & Staff / Sabbatical Fellows / Project Information (via CobWeb/3.1 planetlab2.cs.unc.edu)   (Site not responding. Last check: 2007-10-06)
Speciation, the process of one species splitting into two, can potentially be difficult in the absence of geographic isolation between the two new species.
Reproductive isolation can, however evolve despite sympatry (the coexistence of the incipient pecies in a single location) under certain circumstances.
A special case of divergence in sympatry is reinforcement; this occurs when reproductive isolation continues to evolve between two species that started to diverge when geographically isolated, but came back into secondary contact before speciation was complete.
www.nescent.org.cob-web.org:8888 /people/sabbatical_fellow.php?id=00008   (122 words)

 Social parasite sympatry and the geographic mosaic of coevolution (via CobWeb/3.1 planetlab2.cs.unc.edu)   (Site not responding. Last check: 2007-10-06)
Field experiments had strongly indicated that in sympatry the pirate species interfered with each other, and so we conducted laboratory raiding experiments that manipulated density of the host and its two parasites.
The lab experiments yielded substantial insight to the interaction between social parasites themselves, as well as to their impacts on a shared host.
Our results show that pirate ants in sympatry can affect the geographic mosaic of evolution in unexpected ways.
iussi.confex.com.cob-web.org:8888 /iussi/2006/techprogram/P1968.HTM   (229 words)

 Asteraceae: Heliantheae-Madiinae, UH Botany
One superb example of this type involves D.
ciliolata in a small area of sympatry in Waipahoehoe Gulch on Mauna Kea, Hawaii.
The other 2 hybrid illustrations show an array of shoots (3) and leaves (4), each taken from from a different individual growing in the narrow zone of sympatry in this gulch.
www.botany.hawaii.edu /faculty/carr/darbo_x_dcilg.htm   (195 words)

 Cricket frogs in North Carolina   (Site not responding. Last check: 2007-10-06)
Relatively little research of any kind has been conducted on these two species on the Atlantic slope, and their precise geographical and ecological distributions and degree of reproductive isolation remain unclear.
For my dissertation research, I am examining variation in acoustic signals and morphology of the Acris of North Carolina to determine the degree of sympatry and reproductive isolation between the two species at large and small scales and to assess the role of vocalizations as a reproductive isolating mechanism.
As expected, cricket frogs from the upper Piedmont and lower Coastal Plain, respectively west and east of the putative zone of sympatry near the Fall Zone, have audibly different clicks, regardless of the larger temporal patterns.
www.unc.edu /~micancin/cricketfrogs   (334 words)

 Parapatry - Wikipedia, the free encyclopedia
The two species often have contact at the common boundary of their zones, and speciation occurs in partial, but not complete, isolation.
It contrasts with allopatry where different species are geographically isolated from each other, and sympatry where different species evolve in the same area.
One common model of parapatric speciation is the clinal model.
en.wikipedia.org /wiki/Parapatry   (153 words)

 [No title]   (Site not responding. Last check: 2007-10-06)
Two closely related species that in zones of allopatry have similar morphologies, but in areas of sympatry their morphologies diverge
- the morphologies diverge as a result of competition in the zone of sympatry
- in zones of sympatry the beak depth diverges
cneuro.zool.ohiou.edu /~roosen/ecology/Lec11.html   (1153 words)

 arianne research
I've been using the limnetic/benthic species pairs of threespine sticklebacks to look at how selection in sympatry can enhance reproductive isolation either due to maladaptive hybridization (reinforcement), or by direct selection on mate preferences due to other interactions (i.e.
I've started to address this by looking at differences in male mate preferences between sympatric and allopatric populations of sticklebacks.
My plans are to continue to investigate the effects of selection in sympatry on the evolution of male preferences, using sticklebacks and Mediterranean brine shrimp.
www.zoology.ubc.ca /~albert   (299 words)

 Central Plains Archeology, Volume 4, abstracts
Sympatry-mapping techniques plot the modern ranges of animals whose remains are recovered at a site; the areas containing the greatest overlap of modern ranges represent a fair estimate of local paleoclimate.
By mapping the areas of maximum sympatry for animal species recovered at several contemporaneous or nearly contemporaneous sites, a larger view of the paleoclimate of a region emerges.
Small mammals, by virtue of their sensitivity to microclimatic change, are excellent barometers of paleoclimate.
www.nebraskahistory.org /archeo/napa/cpa4.htm   (665 words)

 Carlton & Leschen--Species in sympatry: Pselaphotheseus of Campbell Island
Carlton and Leschen--Species in sympatry: Pselaphotheseus of Campbell Island
Both species are apparently endemic to Campbell Island, and coexist in sympatry there.
Entomological surveys of New Zealand's subantarctic island groups are incomplete, however, and the genus may be more widespread than is currently recognised.
www.rsnz.org /publish/nzjz/2001/26.php   (110 words)

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