Your SlideShare is downloading. ×
Vikas
Vikas
Vikas
Vikas
Vikas
Vikas
Vikas
Vikas
Vikas
Vikas
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Vikas

335

Published on

Published in: Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
335
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
0
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Ap Chapter 24 The Origin Of Speciesfrom smithbio , 2 years agospecies Modes of speciation Allopatric – geographical for sympatric than allopatricspecies Fig. 24-15 Sympatric40 slides | 2 favorites | Download<br />Registration for WikiConference India 2011, Mumbai is now open. Click here to register. <br />Sympatric speciation<br />From Wikipedia, the free encyclopedia<br />Jump to: navigation, search <br />Part of a series onEvolutionary BiologyKey Topics[show]Evolution (Introduction)Common descentEvidence of common descentHistory of Theory[show]OverviewRenaissance and EnlightenmentBefore DarwinDarwin • His bookBefore the SynthesisModern evolutionary synthesisMolecular evolution • Evo-devoCurrent researchNatural History[show]History of lifeBiodiversity • BiogeographyClassification • CladisticsPaleontologyPhylogenyProcesses & Outcomes[show]Population geneticsVariationMutationNatural selection • AdaptationPolymorphism (biology)Genetic drift • Gene flowSpeciation • Adaptive radiationCo-operation • CoevolutionExtinctionSocial Implications[show]Theory and factSocial effectControversyObjectionsLevel of supportFields & Applications[show]Applications of evolutionArtificial selectionBioinformaticsEvolutionary anthropologyEvolutionary computationExperimental evolutionEcological geneticsEvolutionary neuroscienceEvolutionary physiologyEvolutionary psychologyPhylogeneticsSystematics Evolutionary Biology PortalCategory • Related topics • Bookv · d · e<br />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 they occur together at least in some places. If these organisms are closely related (e.g. sister species), such a distribution may be the result of sympatric speciation. Etymologically, sympatry is derived from the Greek roots συν (together, with) and πατρίς (homeland or fatherland).[1] The term was invented by Poulton in 1904, who explains the derivation.[2]<br />Sympatric speciation is one of three traditional geographic categories for the phenomenon of speciation.[3][4] Allopatric speciation is the evolution of geographically isolated populations into distinct species. In this case, divergence is facilitated by the absence of gene flow, which tends to keep populations genetically similar. Parapatric speciation is the evolution of geographically adjacent populations into distinct species. In this case, divergence occurs despite limited interbreeding where the two diverging groups come into contact. In sympatric speciation, there is no geographic constraint to interbreeding. It has been pointed out that these categories are special cases of a continuum from zero (sympatric) to complete (allopatric) spatial segregation of diverging groups.[4]<br />In multicellular eukaryotic organisms, sympatric speciation is thought to be an uncommon but plausible process by which genetic divergence (through reproductive isolation) of various populations from a single parent species and inhabiting the same geographic region leads to the creation of new species.[5] In bacteria, however, the analogous process (defined as "the origin of new bacterial species that occupy definable ecological niches") might be more common because bacteria are less constrained by the homogenizing effects of sexual reproduction and prone to comparatively dramatic and rapid genetic change through horizontal gene transfer.[6]<br />Contents1 Evidence2 Controversy3 See also4 References5 External links<br />[edit] Evidence<br />Comparison of allopatric, peripatric, parapatric and sympatric speciation<br />A number of models have been proposed to account for this mode of speciation. The most popular, which invokes the disruptive selection model, was first put forward by John Maynard Smith in 1966.[7] Maynard Smith suggested that homozygous individuals may, under particular environmental conditions, have a greater fitness than those with alleles heterozygous for a certain trait. Under the mechanism of natural selection, therefore, homozygosity would be favoured over heterozygosity, eventually leading to speciation. Sympatric divergence could also result from the sexual conflict.[8]<br />Disruption may also occur in multiple-gene traits. The Medium Ground Finch (Geospiza fortis) is showing gene pool divergence in a population on Santa Cruz Island. Beak morphology conforms to two different size ideals, while intermediate individuals are selected against. Some characteristics (termed magic traits) such as beak morphology may drive speciation because they also affect mating signals. In this case, different beak phenotypes may result in different bird calls, providing a barrier to exchange between the gene pools.[9]<br />A well studied circumstance of sympatric speciation is when insects feed on more than one species of host plant. In this case insects become specialized as they struggle to overcome the various plants' defense mechanisms. (Drès and Mallet, 2002)[10]<br />Rhagoletis pomonella, the apple maggot, may be currently undergoing sympatric or, more precisely, heteropatric (see heteropatry) speciation. The apple feeding race of this species appears to have spontaneously emerged from the hawthorn feeding race in the 1800 - 1850 AD time frame, after apples were first introduced into North America. The apple feeding race does not now normally feed on hawthorns, and the hawthorn feeding race does not now normally feed on apples. This may be an early step towards the emergence of a new species. [11] [12] [13] Isolated and relatively homogeneous habitats such as crater lakes and islands are among the best geographical settings in which to demonstrate sympatric speciation. For example, Nicaragua crater lake cichlid fishes include at least one species that has evolved by sympatric speciation [14]<br />Allochrony offers some empirical evidence that sympatric speciation has taken place, as many examples exist of recently diverged (sister taxa) allochronic species.<br />Sympatric speciation events are vastly more common in plants, as they are prone to developing multiple homologous sets of chromosomes, resulting in a condition called polyploidy. The polyploidal offspring occupy the same environment as the parent plants (hence sympatry), but are reproductively isolated.<br />A rare example of sympatric speciation in animals is the divergence of "resident" and "transient" Orca forms in the northeast Pacific.[15] Resident and transient orcas inhabit the same waters, but avoid each other and do not interbreed. The two forms hunt different prey species and have different diets, vocal behaviour, and social structures. Some divergences between species could also result from contrasts in microhabitats.<br />The European Polecat Mustela putorius exhibited a rare dark phenotype similar to the European mink Mustela lutreola phenotype which is directly influenced by peculiarities of forest brooks.[16]<br />[edit] Controversy<br />Debated almost since the beginning of popular evolutionary thought, sympatric speciation is still a highly contentious issue. By 1980 the theory was largely unfavourable given the void of empirical evidence available, and more critically the conditions scientists expect to be required. Ernst Mayr, one of the foremost thinkers on evolution, completely rejected sympatry outright, ushering in a climate of hostility towards the theory. While still debatable, well documented empirical evidence now exists, and the development of sophisticated theories incorporating multilocus genetics has followed.<br />[edit] See also<br />Look up sympatric in Wiktionary, the free dictionary.<br />Environment portalEcology portalEarth sciences portalEvolutionary biology portal<br />Polymorphism (biology)<br />Ecotype<br />Polyploidy<br />Adaptive radiation<br />Hybrid speciation<br />Cladistics<br />Phylogenetics<br />Taxonomy<br />Wallace effect<br />[edit] References<br />^ http://www.greek-language.gr/greekLang/index.html<br />^ Poulton, E. B. 1904. What is a species? Proceedings of the Entomological Society of London 1903:lxxvii-cxvi.<br />^ Futuyma, D. J. 2009. Evolution (2nd edition). Sinauer Associates, Inc.<br />^ a b Fitzpatrick, B. M., J. A. Fordyce, and S. Gavrilets. 2008. What, if anything, is sympatric speciation? Journal of Evolutionary Biology 21: 1452-1459.<br />^ Bolnick, D. I. and B. M. Fitzpatrick. 2007. Sympatric speciation: Models and empirical evidence. Annual Review of Ecology, Evolution and Systematics 38: 459-487.<br />^ King, Stansfield, Mulligan (2006). Dictionary of Genetics (7th ed.). Oxford University Press. <br />^ John Maynard Smith (1966). "Sympatric Speciation". American Naturalist 100 (916): 637–650.  [1]<br />^ Thierry Lodé "La guerre des sexes chez les animaux" Eds O Jacob, Paris, 2006<br />^ *Huber, SK; De León, LF; Hendry, AP; Bermingham, E; Podos, J (2007). "Reproductive isolation of sympatric morphs in a population of Darwin's finches". Proc. Biol. Sci. 274 (1619): 1709–14. doi: HYPERLINK "http://dx.doi.org/10.1098%2Frspb.2007.0224" 10.1098/rspb.2007.0224. PMC 2493575. PMID 17504742. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2493575 <br />^ Begon, Townsend, Harper: Ecology - From individuals to ecosystems, 4th ed., p.10<br />^ McPheron et al. 1988. Nature 336:64-66<br />^ Smith, D.C. 1988. Nature 336:66-67<br />^ Feder et al. 1988. Nature 336:61-64<br />^ Sympatric speciation in Nicaraguan crater lake cichlid fish. By: Barluenga, Marta; Stölting, Kai N.; Salzburger, Walter; Muschick, Moritz; Meyer, Axel. Nature, 2/9/2006, Vol. 439 Issue 7077, p719-723.<br />^ Hoetzel et al. 1998, Low genetic variation among killer whales (Orcinus orca) in the eastern North Pacific and genetic differentiation between foraging specialists, J Hered<br />^ Thierry Lodé "Genetic divergence without spatial isolation in polecat Mustela putorius populations". J Evol Biol 14:228-236, 2001<br />[edit] External links<br />Berkeley evolution 101<br />[hide]v · d · eSpeciationBasic conceptsSpecies · Cline · Chronospecies · SpeciationModes of speciationAllopatric · Heteropatric · Peripatric · Parapatric · Sympatric · Polyploidy · PaleopolyploidyAuxiliary mechanismsSexual selection · Assortative mating · Punctuated equilibriumIntermediate stagesHybrid · Species complex · Ring species · Haldane's rule<br />[show]v · d · e Basic topics in evolutionary biologyEvidence of common descentProcesses of evolutionAdaptation · Macroevolution · Microevolution · SpeciationPopulation genetic mechanismsGenetic drift · Gene flow · Mutation · Natural selectionEvolutionary developmentalbiology (Evo-devo) conceptsCanalisation · Inversion · Modularity · Phenotypic plasticityEvolution of organsand biological processesAging · Avian flight · Cellular · DNA · Eye · Flagella · Hair · Human intelligence · Mammalian auditory ossicles · Mosaic evolution · Multicellular · SexTaxa evolutionBirds · Butterflies · Cephalopods · Dinosaurs · Dolphins and whales · Fish · Fungi · Horses · Humans · Influenza · Insects · Lemur · Life · Mammals · Molluscs · Plants · Sirenians (sea cows) · Spiders · VirusesModes of speciationAnagenesis · Catagenesis · CladogenesisHistory of evolutionary thoughtCharles Darwin · On the Origin of Species · Modern evolutionary synthesis · Gene-centered view of evolution · Life (classification trees)Other subfieldsEcological genetics · Molecular evolution · Phylogenetics · SystematicsList of evolutionary biology topics · Timeline of evolution<br />Retrieved from "http://en.wikipedia.org/w/index.php?title=Sympatric_speciation&oldid=452673763" <br />View page ratings<br />Rate this page<br />Rate this page<br />Page ratings<br />What's this?<br />Current average ratings.<br />Trustworthy<br />Objective<br />Complete<br />Well-written<br />I am highly knowledgeable about this topic (optional) <br />I have a relevant college/university degree<br />It is part of my profession<br />It is a deep personal passion<br />The source of my knowledge is not listed here<br />I would like to help improve Wikipedia, send me an e-mail (optional) <br />We will send you a confirmation e-mail. We will not share your address with anyone. (Privacy policy)<br />Submit ratings <br />Saved successfully<br />Your ratings have not been submitted yet<br />Your ratings have expired<br />Please reevaluate this page and submit new ratings.<br />An error has occured. Please try again later.<br />Thanks! Your ratings have been saved.<br />Please take a moment to complete a short survey.<br />Start surveyMaybe later <br />Thanks! Your ratings have been saved.<br />Do you want to create an account?<br />An account will help you track your edits, get involved in discussions, and be a part of the community.<br />Create an accountorLog inMaybe later <br />Thanks! Your ratings have been saved.<br />Did you know that you can edit this page?<br />Edit this pageMaybe later <br />Categories: <br />Ecology<br />Evolutionary biology<br />Speciation<br />Scientific classification<br />Taxonomy<br />Personal tools<br />Log in / create account<br />Namespaces<br />Article<br />Discussion<br />Variants<br />Views<br />Read<br />Edit<br />View history<br />Actions<br />Search<br />Top of Form<br />Bottom of Form<br />Navigation<br />Main page<br />Contents<br />Featured content<br />Current events<br />Random article<br />Donate to Wikipedia<br />Interaction<br />Help<br />About Wikipedia<br />Community portal<br />Recent changes<br />Contact Wikipedia<br />Toolbox<br />What links here<br />Related changes<br />Upload file<br />Special pages<br />Permanent link<br />Cite this page<br />Rate this page<br />Print/export<br />Create a book<br />Download as PDF<br />Printable version<br />Languages<br />Català<br />Deutsch<br />Español<br />Қазақша<br />Nederlands<br />Polski<br />Português<br />Русский<br />Svenska<br />Українська<br />This page was last modified on 27 September 2011 at 10:41.<br />Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. See Terms of use for details.Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.<br />Contact us<br />Privacy policy<br />About Wikipedia<br />Disclaimers<br />Mobile view<br />Origin Of Species Sargunan Kaveripakkamfrom sargunan7 , 1 year agoOrigin Of Species,Sargunan Kaveripakkam The Origin of Species New species are formed10 pages | Download<br />OHHS AP Bio Chapter 24 Presentationfrom jayswan , 1 year agofor sympatric than allopatric species Fig. 24-15 Sympatric Other species Allopatricmales 0 4 8 12 16 20 24 28 Fig109 slides | Download<br />BIOL 102 General Biology II - Chp 24: The Origin of Speciesfrom robswatski , 1 year agoon Chapter 24: The Origin of Species (Biology 8E by Campbell et al, 2008). Rob Chapter 24 The Origin of Species88 slides | 2 favorites | Download<br />Winkles and the origin of speciesfrom guest9eed32 , 1 year agothe first seminar in the ACEBB Science Seminar Series entitled "Winkles and the origin of species". of species Professor Roger Butlin Winkles38 slides | Download<br />Winkles and the origin of speciesfrom guest372cdf , 1 year agothe first seminar in the ACEBB Science Seminar Series entitled "Winkles and the origin of species". of species Professor Roger Butlin Winkles| Download<br />Winkles and the origin of speciesfrom guest372cdf , 1 year agothe first seminar in the ACEBB Science Seminar Series entitled "Winkles and the origin of species". of species Professor Roger Butlin Winkles38 slides | Download<br />Chapter 14 The Origin of Speciesfrom pisgahscience , 1 year agoChapter 14 The Origin of Species 0 Mosquito Mystery Speciation is the emergence of new species In England and North America Two species of mosquitoes34 slides | Download<br />

×