Extreme phylogeography in Carex (Cyperaceae)

DARWIN commi ed wo chap e s o The O igin o he Species (1872) o explain he pas and p esen dis- ibu ion o he species. He s a ed ha pa e ns o species dis ibu ion may o en be seen as clea oo - s eps o hei e olu ion and di e si ica ion. Thus, p esen -day axa dis ibu ion may be equen ly explained by a combina ion o his o ical e en s (cli- ma ic oscilla ions like a idi ica ions o glacia ions; geological mo emen s like pla e ec onics o o oge- nies) and e olu iona y p ocesses (ex inc ion, ica i- ance, dispe sal...). One o he mos ascina ing dis ibu ion pa e ns is ange disjunc ion. The la ges and mos challenging disjunc ion o biologis s, he bipola dis ibu ion, al eady cap i a ed HUMBOLDT (1817) and DARWIN (1859) who ealized he exis ence o common plan species in he lo a o emo ely dis an a eas (Tie a del Fuego in he sou he n hemisphe e and No he n Eu ope/No h Ame ica in he no he n). DARWIN (1872) ied o explain his disjunc ion as a o ced mig a ion o species due o clima e change. Du ing glacial pe iods, he ad ance o he ice-shee in he no he n hemisphe e migh ha e pushed a c ic species owa ds lowe la i udes; hen, a emig a ion would ha e occu ed on he e u ning wa m h, since hose lowland a eas a e oo wa m o hei exis ence. Some species migh ha e ound a e ugium in moun- ain summi s in sou he n la i udes in s ead o mo - ing no hwa d. DARWIN (1859) hen hough ha he e we e ew species iden ically he same in bo h hemisphe es and on he moun ains o in e media e opical egions, whose mu ual ela ions will no ha e been much dis u bed. Admi ably, he s a ed all hese hypo heses wi hou e en knowing he exis ence o he gene ic ma e ial. Phylogeog aphy is a ising discipline ha ies o unde s and he easons o he dis ibu ion o species and closely ela ed gene ic lineages, o e ime and he e olu iona y p ocesses in ol ed (AVISE e al., 1987; AVISE, 2000). This discipline eme ged in a mul idis- ciplina y con ex and i in eg a es me hods and con- cep s om popula ion gene ics (mic oe olu ion) and om sys ema ics (mac oe olu ion). Bipola biogeog aphy is s ill he ocus o nume ous s udies a e Da win’s i s app oach based on o gan- ism mig a ions (DURIETZ, 1940; WILSON, 1986; MOORE, CHATER, 1971; MOORE, 1972; SMITH, 1986; BALL, 1990). Resea che s ha e p oposed di - e en hypo heses o un a el he e olu iona y his o y o bipola axa based on molecula and mo phologi- cal da a (ESCUDERO e al., 2010; POPP e al., 2011). The objec i e o his wo k is o b ie ly e iew he hypo heses sugges ed o explain bipola disjunc ions and how o es hem wi h molecula echniques. BIPOLAR DISTRIBUTIONS IN CAREX MOORE, CHATER (1971) e med bipola species ol- lowing a single and simple c i e ion: such species mus each la i udes as high as he Eu opean A c ic o Alaska (c. 55º N. la .) in he no he n hemisphe e and he S aigh o Magellan (c. 52º S. la .) in he sou he n hemisphe e, ega dless o hei occu ences elsewhe e. Unde his c i e ion, hey poin ed 30 species belonging o 12 amilies (Tab. 1) and 23 gen- e a, 6 o hem (20%) co esponding o he genus 58 I NFORMATORE B OTANICO I TALIANO , 44S UPPL . 2, 2012 Ex eme phylogeog aphy in Ca ex (Cype aceae) T. VILLAVERDE, S. MARTÍN-BRAVO, M. ESCUDERO and M. LUCEÑO RIASSUNTO - Filogeog a ia di es emi à di a eale in Ca ex (Cype aceae)- Le disgiunzioni negli a eali di dis ibuzione dei axa hanno susci a o l’in e esse dei na u alis i sin dall’inizio del XIX secolo. Sono no e solo en a specie a en i dis ibu- zione bipola e e Ca ex isul a il gene e con il maggio nume o di specie bipola i. Una disciplina eme gen e, la ilogeog a- ia, do ebbe esse e usa a pe es a e le ipo esi sulle specie bipola i poiché en a di spiega e le cause e i p ocessi di e olu- zione ela i i alla dis ibuzione delle specie e alle lo o elazioni gene iche. Sono p opos e di e se ipo esi pe spiega e le dis- giunzioni bipola i: ica ianza, pa allelismo, con e genza, dispe sione a lunga dis anza e spos amen o a balzi sui ilie i. Key wo ds: bipola disjunc ions, Ca ex, long dis ance dispe sal, moun ain hopping, pa allelism, phylogeog aphy, ica iance INTRODUCTION A i Riunione Scien i ica Sezione Piemon e - Valle d’Aos a Ca ex L. (Cype aceae). Al hough Poaceae amily has 8 bipola species, hey a e belonging o h ee di e en gene a (Phleum, Poa and Deschampsia). Then, Ca ex is he genus wi h mo e bipola species. Why such a s iking pa e n is so commonly ound wi hin Ca ex? This is no only he la ges genus wi hin he Cype aceae amily, wi h mo e han 2.000 species (KÜKENTHAL, 1909) dis ibu ed ac oss all lo is ic egions (REZNICEK, 1990), bu also he mos di e se angiospe m genus o he no he n empe a e zone (ESCUDERO e al., 2012). I con ains many cold- adap ed species ha a e eligible o ha e eached ex eme la i udes in bo h hemisphe es and, he e o e, he bipola dis ibu ion. Amphi opical species o lowe la i udes migh no be conside ed as bipola because hei en i onmen al and biological his o ies a e likely o sepa a e hem om he a c ic-alpine lo a when in es iga ing he ac o s in ol ed in he pa e ns o hei dis ibu ions (RAVEN, 1963). Ca ex is di ided in ou sub-gene a based on mo pho- logical and molecula da a (STARR, FORD, 2009). Th ee o hem ha e a leas one bipola species: C. a c ogena H.Sm. and C. mic oglochin Wahlenb. in subgenus Psyllopho a (Degl.) Pe e m.; C. canescens L., C. maclo iana D’U . and C. ma i ima Gunn. in sub- genus Vignea (P. Beau . ex Les ib. .) Pe e m.; C. mag- ellanica Lam. in subgenus Ca ex L. All hese species a e p esen in Tie a del Fuego (Pa agonia, A gen ina) and in a c ic-alpine a eas o Eu asia and No h Ame ica. Ca ex canescens is also p esen in Aus alia. A de ailed axonomic s udy o each bipola species encompassing popula ions ac oss i s ange should be manda o y be o e u he s eps owa ds elucida ing he o igin o such disjunc ions. Fo example, some popula ions o C. mic oglochin in Sou h Ame ica we e ound o belong o a di e en species, C. camp- oglochin (WHEELER, GUAGLIANONE, 2003). HYPOTHESES TO TEST Once he axonomy o he bipola species has been clea ly sol ed, i is possible o s udy hei biogeog a- phy and e olu iona y ela ionships. The geog aphi- cal sepa a ion ound in bipola species migh be con- side ed as a majo ac o dis up ing he pa e n o gene low. I gene ic isola ion allows no he n and sou he n popula ions o di e ge sepa a ely, i may lead o he accumula ion o molecula and mo pho- logical di e ences o clea ly dis inguish hem. Di e en deg ees o di e en ia ion may accoun o di e en hypo heses. VICARIANCE, PARALLELISM AND CONVERGENCE Molecula di e ences be ween No he n and Sou he n Hemisphe e popula ions migh be due o hei dissimila e olu ion. Popula ions migh ha e es ed gene ically isola ed o agmen ed, allowing a dis inc molecula di e gence bu no a mo phologi- cal one. To ejec ica iance hypo hesis, es ima ion o di e - gence imes may help o es he cong uence be ween phylogene ic spli s and ecological equi emen s. The ela i e age o his disjunc ion was e alua ed h ough es ima ion o di e gence imes and ossil e idences. Pa allelism o con e gence hypo heses imply he accumula ion o e olu iona y s eps in he same ash- ion in no he n and sou he n popula ions o dis an - ly ela ed lineages, in his case popula ions would belong o polyphyle ic g oups. The e o e, o ejec hese hypo heses, ex eme edges popula ions mus be shown as oge he monophyle ic. DIRECT LONG DISTANCE DISPERSAL I he e a e no obse ed molecula di e ences be ween popula ions, i migh be possible o consid- e a long dis ance dispe sal hypo hesis, occu ed in ecen imes. To ejec his hypo hesis, popula ions a he ex emes o he dis ibu ion mus belong o ancien monophyle ic di e gen g oups. ESCUDERO e al. (2010) sampled i e o he six bipo- la Ca ex species (C. a c ogena was no included) o a molecula app oach and sugges ed long-dis an dis- pe sal, sensu la o, as he mos plausible cause o bipo- la disjunc ion o C. canescens, C. maclo iana, C. magellanica and C. ma i ima. Al hough al e na i e dispe sal hypo heses (e.g. di ec long-dis an dispe - sal) could no be es ed due o hei sampling m hod, genealogical ela ionships o chlo oplas haplo ypes indica ed a sou hwa ds di ec ion o dis- pe sal o C. canescens, C. maclo iana and C. magel- lanica (ESCUDERO e al., 2010). MOUNTAIN HOPPING The moun ain-hopping hypo hesis (BALL, 1990) elies on he idea ha species ha e p og essi ely mig a ed om one moun ain chain o he nex (as s epping-s ones) h ough he low la i ude egions o achie e such dis ibu ion (MOORE, CHATER, 1971; VOLLAN e al., 2006). Unde his hypo hesis, i a 59A i Riunione Scien i ica Sezione Piemon e - Valle d’Aos a TABLE 1 Numbe o bipola species in ascula plan s amilies (MOORE, CHATER, 1971). Nume o delle specie bipola i nell’ambi o delle amiglie di pian e ascola i (MOORE, CHATER, 1971). Family Numbe Lycopodiaceae P. Beau . ex Mi b. 1 Plumbaginaceae Juss. 1 Gen ianaceae Juss. 1 Sc ophula iaceae Juss. 1 Juncaginaceae Rich. 1 Hymenophyllaceae Ma . 2 Polygonaceae Juss. 2 Ranunculaceae Juss. 2 Plan aginaceae Juss. 2 Ca yophyllaceae Juss. 3 Cype aceae Juss. 6 Poaceae Ba nha 8 b oad sampling o he dis ibu ion a eas is ob ained, nea by popula ions should ha e highe molecula a ini y han he popula ions a he ex eme o he dis ibu ion. To ejec his hypo hesis, molecula dis- simila i ies mus no clea ly dis inguish no he n and sou he n popula ions. MEANS OF DISPERSAL Al hough some mechanisms and synd omes o dis- pe sal ha e been desc ibed wi hin he genus Ca ex (ALLESSIO LECK, SCHÜTZ, 2005) i gene ally lacks o any means o long-dis ance dispe sal (STEENIS VAN, 1962; RAVEN, 1963). Only wo bipola species, C. maclo iana and C. mic oglochin, display some ea- u es o dispe sal (winged and hooked u icules, espec i ely, MASTROGIUSEPPE e al., 2002; SAVILE, 1972). Howe e , he e is no enough e idence o explain such wide dissemina ion simply by mo pho- logical dispe sal peculia i ies (ESCUDERO e al., 2010). DARWIN (1859) sugges ed ha some plan s migh also be in luenced by occasional ec o s o dis ibu- ion such as sea wa e (su i al in sea wa e o days in spi e o no being adap ed o his mean o dispe - sal) o bi ds (adhe ing o oo o kep in bi d giz- za ds). RAVEN (1963) also poin ed o bi ds as impo - an ec o s in plan dispe sal, sugges ing ha many o he disjunc ions, such as bipola o amphi- A lan ic, co espond wi h bi d mig a ion ou es. An example o a ecen long dis an dispe sal a ou ed by bi ds was p oposed in Emp e um (POPP e al., 2011). CONCLUSIONS The ac ha bipola species’ axonomy is o en un e- sol ed (e.g. A me ia ma i ima Willd., BAUMBACH, HELWIG, 2007; Osmo hiza be e oi DC., WEN e al., 2002) could be a p oblem when in e p e ing molec- ula esul s. Besides, he exac numbe o bipola species migh luc ua e when hey a e he subjec o axonomic e isions (MOORE, CHATER, 1971). While es ing hypo heses o bipola disjunc ions in clea biological en i ies, nuclea and chlo oplas DNA a e ecommended o be explo ed. Nuclea DNA (e.g. ITS egion, nuclea low copy genes, o AFLPs pheno ypes) is commonly used in biogeo- g aphical s udies and gi es enough e idence o eluci- da e whe he he e is gene low be ween popula ions. On he o he hand, chlo oplas DNA (e.g. ma k, ps16, nL) is sui able o econs uc phylogeog aph- ical pa e ns and ollow plan dispe sion di ec ions, by pe o ming analyses such as haplo ype ne wo k es ima ions. Once he axonomy o a species g oup is sol ed and accu a e phylogenies a e made, es ima ion o lineage di e gence imes could be in e ed. Al hough ossil e idence in Ca ex is sca ce (SMITH e al., 2009), a emp s o da e specia ion e en s such as ha conduc ed by DRAGON, BARRINGTON (2009) could acili a e he unde s anding o e olu iona y p ocesses in he genus. Acknowledgemen s -.The au ho s would like o hank he Socie à Bo anica I aliana o he in i a ion o p esen his communica ion a he Symposium on Cype aceae 2012, and especially E. Ma ine o and A. Pis a ino o he sup- po gi en a he mee ing. LITERATURE ALLESSIO LECK M., SCHÜTZ W., 2005 – Regene a ion o Cype aceae, whi pa icula e e ence o seed ecology and seed banks. Pe spec . Plan Ecol. E ol. Sys . 7: 95-133. AVISE J.C., 2000 – Phylogeog aphy: he his o y and o ma- ion o species. Ha a d Uni e si y P ess, Camb idge, Massachuse s, USA. AVISE J.C., ARNOLD J., BALL R.M. JR, BERMINGHAM E., LAMB T., NEIGEL J.E., REEB C.A., SAUNDERS N.C., 1987 – In aspeci ic phylogeog aphy: he mi ochond ial DNA b idge be ween popula ion gene ics and sys ema ics. Ann. Re . Ecol. Sys ., 18: 489-522. BALL P.W., 1990 – Some aspec s o he phy ogeog aphy o Ca ex.Can. J. Bo ., 68: 1462-1472. BAUMBACH H., HELLWIG F.H., 2007 – Gene ic di e en ia- ion o me allicolous and non-me allicolous A me ia ma i ima (Mill.) Willd. axa (Plumbaginaceae) in cen- al Eu ope. Plan Sys . E ol., 269: 245-258. DARWIN C., 1859 – On he O igin o he Species by Means o Na u al Selec ion, o he Pe se a ion i Fa ou ed Ra es in he S uggle o Li e. Mu ay, London. —, 1872 – The O igin o he Species. Mu ay, London, 6 h ed. DRAGON J.A., BARRINGTON D.S., 2009 – Sys ema ics o he Ca ex aqua ilis and Ca ex len icula is lineages: Geog aphically and ecologically di e gen sis e clades o Ca ex sec ion Phacocys is (Cype aceae). Am. J. Bo ., 96: 1896-1906. DURIETZ G.E., 1940 – P oblems o he bipola plan dis i- bu ion. Ac a Phy ogeog aphica Suecica, 13: 215-282. ESCUDERO M., HIPP A.L., WATERWAY M.J., VALENTE L.M., 2012 – Di e si ica ion a es and ch omosome e o- lu ion in he mos di e se angiospe m genus o he empe - a e zone (Ca ex, Cype aceae). Mol., Phyl. E ol., 63(3), 650-655. ESCUDERO M., VARCÁRCEL V., VARGAS P., LUCEÑO M., 2010 – Bipola disjunc ions in Ca ex: long-dis an dispe - al, ica iance o pa allel e olu ion?. Flo a, 205: 118-127. HUMBOLDT F.W.H., 1817 – De dis ibu ione geog aphica pla a um secundum coeli empe iem e al i udem mon- ium, P olegomena. Lib a ia g aeco-la ino-ge manica, Pa is. KÜKENTHAL G., 1909 – Cype aceae-Ca icoideae. In: ENGLER A. (Ed.), Das P lanzen eich, IV(20): 1-814. Engelmann, Leipzig. MASTROGIUSEPPE J., ROTHROCK P.E., DIBBLE A.C., REZNICEK A.A., 2002 – Ca ex L. sec . O ales Kun h. In: FLORA OF NORTH AMERICA EDITORIAL COMMITTEE (Ed.), Flo a o No h Ame ica No h o Mexico, ol. 23: 332-378. Ox o d Uni e si y P ess, New Yo k. MOORE D.M., 1972 – Connec ions be ween cool empe a e lo as, wi h pa icula e ence o sou he n Sou h Ame ica. In: VALENTINE D.H. (Ed.), Taxonomy, Phy ogeog aphy and E olu ion: 115-138. Academic P ess, London. MOORE D.M., CHATER A.O., 1971 – S udies on bipola species I. Bo . No ., 124: 317-334. POPP M., MIRRÉ V., BROCHMAN C., 2011 – A single mid- Pleis ocene long-dis ance dispe sal by a b id can explain he ex eme bipola disjunc ion in c owbe is (Empe um). P oc. Na . Acad. Sci., 108: 6520-6525. 60 I NFORMATORE B OTANICO I TALIANO , 44S UPPL . 2, 2012 RAVEN P.H., 1963 – Amphi opical ela ionships in he lo- as o No h and Sou h Ame ica. Qua . Re . Biol., 38: 151-177. REZNICEK A.A., 1990 – E olu ion in sedges (Ca ex, Cype aceae). Can. J. Bo ., 68: 1409-1432. SAVILE D.B.O., 1972 – A c ic adap a ions in plan s. Monog aph 6, Resea ch B anch, Canada Depa men o Ag icul u e, O awa. SMITH J.M.B., 1986 – O igins o he Aus alasian opi- calpine and alpine lo as. In: BARLOW B.A. (Ed.), Flo a and Fauna o Alpine Aus alia: 109-128. CSIRO, Melbou ne. SMITH S.Y., COLLINSON M.E., SIMPSON D.A., RUDALL P.J., STAMPANONI F.M., 2009 – Elucida ing he a ini- ies and habi a o ancien , widesp ead Cype aceae: Volke ia messelensis gen. e sp. no ., a ossil mapanoid sedge om he Eocene o Eu ope. Am. J. Bo ., 96: 1506- 1518. STARR J.R., FORD B.A., 2009 – Phylogeny and e olu ion in Ca iceae (Cype aceae): cu en knowledge and u u e di ec ions. Bo . Re ., 75: 110-137. STEENIS C.G. VAN, 1962 – The moun ain lo a o he Malaysian opics. Endea ou , 21: 183-193. VOLLAN K., HEIDE O., HEUN M., 2006 – Gene ic a ia- ion, axonomy and moun ain-hopping o ou bipola Ca ex species (Cype aceae) analysed by AFLP inge - p in ing. Aus alian J. Bo ., 54: 304-313. WEN J., PORTER P.P., LOWRY I.I., WALCK J.L., YOO K., 2002 – Phylogene ic biogeog aphic di e si ica ion in Osmo hiza (Apiaceae). Ann. Missou i Bo . Ga den, 89: 414-428. WHEELER G.A., GUAGLIANONE E.R., 2003 – No es on Sou h Ame ican Ca ex (Cype aceae): C. camp oglo- chin and C. mic oglochin. Da winiana, 41: 193-206. WILSON J.B., 1986 – Alpine species o Cype aceae and Juncaceae.In: BARLOW B.A. (Ed.), Flo a and Fauna o Alpine Aus alia: 472-488. CSIRO, Melbou ne. ABSTRACT - G ea dis ibu ion disjunc ions o axa ha e cap i a ed na u alis s since he beginning o he XX h cen u y. Only hi y species a e known o ha e a bipola dis ibu ion, being Ca ex he genus wi h he la ges numbe o bipola species. A ising discipline, phy- logeog aphy, could be used o es o hypo heses in bipo- la species since i ies o unde s and he easons and he e olu iona y p ocesses in ol ed o he dis ibu ion o species and hei closely ela ed gene ic lineages. Di e en hypo heses a e sugges ed o bipola disjunc ions: ica i- ance, pa allelism, con e gence, long dis an dispe sal and moun ain hopping. 61A i Riunione Scien i ica Sezione Piemon e - Valle d’Aos a AUTHORS Tama a Villa e de ( [email protected]), San iago Ma ín-B a o, Ma cial Escude o, Modes o Luceño, Á ea de Bo ánica, Depa amen o de Biología Molecula e Ingenie ía Bioquímica, Uni e sidad Pablo de Ola ide, C . de U e a s/n, 41008 Se illa, Spain