{"id":5005616,"date":"2007-07-05T23:14:13","date_gmt":"2007-07-05T21:14:13","guid":{"rendered":"https:\/\/criticalbiomass.blog.hu\/2007\/07\/05\/kisegerek"},"modified":"2007-07-05T23:14:13","modified_gmt":"2007-07-05T21:14:13","slug":"kisegerek","status":"publish","type":"post","link":"https:\/\/criticalbiomass.hu\/?p=5005616","title":{"rendered":"Kisegerek"},"content":{"rendered":"<p>\n<img decoding=\"async\" src=\"http:\/\/criticalbiomass.blog.hu\/media\/image\/200707\/stuart_little.jpg\" align=\"left\" hspace=\"5\" vspace=\"5\" \/>A szigetek \u00e9l\u0151vil\u00e1ga mindig k\u00fcl\u00f6nleges, gondoljunk csak \u00daj Z\u00e9land eg\u00e9szen egyedi mad\u00e1r faun\u00e1j\u00e1ra vagy Galapagos pintyeire \u00e9s <a href=\"http:\/\/www.oiseaux.net\/photos\/frederic.leviez\/cormoran.aptere.4.html\">r\u00f6pk\u00e9ptelen kormor\u00e1nj\u00e1ra<\/a>. A szigeteken az evol\u00faci\u00f3 n\u00e9h\u00e1ny el\u00e9g j\u00f3l megj\u00f3solhat\u00f3 szab\u00e1ly ment\u00e9n gyurm\u00e1zik a k\u00fcl\u00f6nb\u00f6z\u0151 form\u00e1kkal: p\u00e9ld\u00e1ul ragadoz\u00f3k hi\u00e1ny\u00e1ban a madarak \u00e1ltal\u00e1ban elvesz\u00edtik rep\u00fcl\u00e9si k\u00e9pess\u00e9g\u00fcket, de legal\u00e1bb ennyire gyakorinak t\u0171nik az is, hogy a szigeteken \u00e9l\u0151 fajok m\u00e9rete az id\u0151k folyam\u00e1n cs\u00f6kkeni fog (ui. a szigeten rendelkez\u00e9sre \u00e1ll\u00f3 t\u00e1pl\u00e1l\u00e9k forr\u00e1sok \u00e1ltal\u00e1ban igencsak v\u00e9gesek, \u00e9s az egyik alkalmazkod\u00e1si lehet\u0151s\u00e9g ehhez a helyzethez, hogy eleve kevesebbre van sz\u00fcks\u00e9g\u00fcnk). Ez az oka pl. a <a href=\"http:\/\/en.wikipedia.org\/wiki\/Dwarf_elephant\">m\u00e1ltai t\u00f6rpeelef\u00e1nt<\/a>, a <a href=\"http:\/\/criticalbiomass.blog.hu\/media\/image\/200707\/\">floresi hobbit<\/a> \u00e9s p\u00e1r <a href=\"http:\/\/criticalbiomass.blog.hu\/media\/image\/200707\/\">Sauropoda din\u00f3 faj<\/a> apr\u00f3 m\u00e9ret\u00e9nek is \u00e9s lehet, hogy hamarosan j\u00f3p\u00e1r fajjal gazdagodik majd ez a lista.\n<\/p>\n<p>\nUgyanis, ha hinni lehet egy \u00faj tanulm\u00e1nynak, az emberi tev\u00e9kenys\u00e9g k\u00f6vetkezt\u00e9ben n\u00f6vekedni fog a t\u00f6p\u00f6r\u00f6d\u0151 fajok sz\u00e1ma, ui. nek\u00fcnk k\u00f6sz\u00f6nhet\u0151en egyre t\u00f6bb a &quot;sziget&quot;. Na ne romantikus, tr\u00f3pusi atollokra tess\u00e9k gondolni (azok t\u00e9nyleges sz\u00e1ma igencsak \u00fagy t\u0171nik, hogy <a href=\"http:\/\/criticalbiomass.blog.hu\/media\/image\/200707\/\">cs\u00f6kkeni fog<\/a>), hanem \u00e9l\u0151hely &quot;szigetekre&quot;. Az \u00e9l\u0151helyek (pl. erd\u0151k, \u00e1rterek) a folyamatos emberi terjeszked\u00e9s miatt ugyanis fragment\u00e1l\u00f3dnak, azaz egyre kisebb darabokra t\u00f6redeznek \u00e9s ezek az \u00e9l\u0151hely-&quot;szigetek&quot; a benn\u00fck rekedt fajok szempontj\u00e1b\u00f3l nem sokban k\u00fcl\u00f6nb\u00f6znek a val\u00f3di szigetekt\u0151l: m\u00e9ret\u00fckn\u00e9l fogva csak limit\u00e1lt t\u00e1pl\u00e1l\u00e9kforr\u00e1st tudnak biztos\u00edtani.\n<\/p>\n<p>\n<img decoding=\"async\" src=\"http:\/\/criticalbiomass.blog.hu\/media\/image\/200707\/fragmentation-body_length.jpg\" align=\"right\" hspace=\"5\" vspace=\"5\" \/>A Washington \u00e1llamban v\u00e9gzett kutat\u00e1s v\u00e9g\u00e9n a kutat\u00f3k, t\u00f6bb r\u00e1gcs\u00e1l\u00f3- (eg\u00e9r- ill. pocok-) fajt vizsg\u00e1lva  arra jutottak, hogy azok m\u00e9rete az ut\u00f3bbi mintegy h\u00e1rom \u00e9vtized alatt (ennyi a max. kora a vizsg\u00e1lt \u00e9l\u0151hely-t\u00f6red\u00e9keknek) szignifik\u00e1nsan cs\u00f6kkent m\u00e1s \u00e9l\u0151helyen leledz\u0151 rokonaikhoz k\u00e9pest. Mivel az egerek am\u00fagy is igen sikeresek <a href=\"http:\/\/criticalbiomass.blog.hu\/media\/image\/200707\/\">a k\u00fcl\u00f6nb\u00f6z\u0151 \u00e9l\u0151helyekhez val\u00f3 alkalmazkod\u00e1sban<\/a>, a cs\u00f6kken\u0151 trend (ami az eddigi \u00f6kol\u00f3giai ismereteink alapj\u00e1n nem meglep\u0151, l\u00e1sd fenn) megjelen\u00e9se nem teljesen v\u00e1ratlan, de a sebess\u00e9ge akkor is figyelemre m\u00e9lt\u00f3. \n<\/p>\n<hr \/>\n<p><font size=\"1\"><strong>Lomolino, MV, Perault, DR<\/strong> (2007) Body size variation of mammals in a fragmanted, temperate rainforrest. <i>Conservation Biology<\/i> doi: 10.1111\/j.1523-1739.2007.00727.x<br \/>\n<\/font><\/p>\n","protected":false},"excerpt":{"rendered":"<p>A szigetek \u00e9l\u0151vil\u00e1ga mindig k\u00fcl\u00f6nleges, gondoljunk csak \u00daj Z\u00e9land eg\u00e9szen egyedi mad\u00e1r faun\u00e1j\u00e1ra vagy Galapagos pintyeire \u00e9s r\u00f6pk\u00e9ptelen kormor\u00e1nj\u00e1ra. A szigeteken az evol\u00faci\u00f3 n\u00e9h\u00e1ny el\u00e9g j\u00f3l megj\u00f3solhat\u00f3 szab\u00e1ly ment\u00e9n gyurm\u00e1zik a k\u00fcl\u00f6nb\u00f6z\u0151 form\u00e1kkal: p\u00e9ld\u00e1ul ragadoz\u00f3k hi\u00e1ny\u00e1ban a madarak \u00e1ltal\u00e1ban elvesz\u00edtik &hellip; <a href=\"https:\/\/criticalbiomass.hu\/?p=5005616\">Egy kattint\u00e1s ide a folytat\u00e1shoz&#8230;. <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-5005616","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=\/wp\/v2\/posts\/5005616","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5005616"}],"version-history":[{"count":0,"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=\/wp\/v2\/posts\/5005616\/revisions"}],"wp:attachment":[{"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5005616"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5005616"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/criticalbiomass.hu\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5005616"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}