{"id":39658,"date":"2026-03-30T00:59:07","date_gmt":"2026-03-30T00:59:07","guid":{"rendered":"https:\/\/www.europesays.com\/cz\/39658\/"},"modified":"2026-03-30T00:59:07","modified_gmt":"2026-03-30T00:59:07","slug":"osel-cz-zahada-obriho-hmyzu-proc-kolem-nas-neletaji-skoro-metrove-vazky","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/cz\/39658\/","title":{"rendered":":: OSEL.CZ :: – Z\u00e1hada ob\u0159\u00edho hmyzu: Pro\u010d kolem n\u00e1s nel\u00e9taj\u00ed (skoro) metrov\u00e9 v\u00e1\u017eky?"},"content":{"rendered":"\n

Na p\u0159elomu karbonu a permu, kdy\u017e doned\u00e1vna vlhk\u00fd tropick\u00fd sv\u011bt uheln\u00fdch ba\u017ein a prales\u016f vychladl, nad Pangeou l\u00e9tal bizarn\u00ed obrovsk\u00fd hmyz. Dnes dr\u00e1\u017ed\u00ed na\u0161i fantazii a nejsp\u00ed\u0161 i no\u010dn\u00ed m\u016fry \u2013 p\u0159itom ale st\u00e1le nev\u00edme, pro\u010d vlastn\u011b byl tak velik\u00fd a dneska nen\u00ed. Nov\u00fd v\u00fdzkum vyvrac\u00ed p\u0159edstavu, \u017ee za to mohl tehdej\u0161\u00ed kysl\u00edk, kter\u00e9ho bylo v atmosf\u00e9\u0159e mnohem v\u00edc ne\u017e dnes.<\/p>\n

\t\t\"Krasavec<\/a><\/p>\n

Krasavec meganeuropsis. Kredit: Werner Kraus, Wikimedia Commons, CC BY-SA 4.0.<\/p>\n

P\u0159ed zhruba 300 miliony byla Zem\u011b v\u00a0mnoha ohledech jin\u00e1 ne\u017e dneska. Kontinenty byly v\u00edcem\u00e9n\u011b sra\u017een\u00e9 do superkontinentu Pangea. V\u00a0tropech, co\u017e tehdy byla i st\u0159edn\u00ed Evropa, se je\u0161t\u011b dr\u017eely zbytky uheln\u00fdch prales\u016f a kolem u\u017e vznikalo uhl\u00ed. Sv\u011bt byl ale vlastn\u011b zastydl\u00fd ve velice dlouh\u00e9 dob\u011b ledov\u00e9 zn\u00e1m\u00e9 jako Karoo (Karoo Ice Age), a sou\u010dasn\u011b bylo ve vzduchu tolik kysl\u00edku, \u017ee d\u0159evo bylo mo\u017en\u00e9 vzn\u00edtit snad i pohledem.<\/p>\n

\u00a0<\/p>\n

\"Edward<\/a><\/p>\n

Edward Snelling. Kredit: University of Pretoria.<\/p>\n

V\u00a0krajin\u011b tehdy \u017eili rozmanit\u00ed starobyl\u00ed obratlovci, ale jedn\u00edm z\u00a0nejv\u00edce ikonick\u00fdch symbol\u016f t\u00e9hle pozoruhodn\u00e9 doby na p\u0159elomu karbonu a permu bezesporu je ob\u0159\u00ed hmyz a dal\u0161\u00ed \u010dlenovci. Kdo by si nezamiloval velikou v\u00e1\u017eku z\u00a0Cesty do prav\u011bku? Od doby, co jsme ve fosiln\u00edm z\u00e1znamu na\u0161li gigantick\u00e9 b\u011bhaj\u00edc\u00ed i l\u00e9taj\u00edc\u00ed hmyz\u00e1ky, nad n\u00e1mi ale vis\u00ed z\u00e1hada. Pro\u010d vlastn\u011b byli tak velc\u00ed a pro\u010d u\u017e dneska nejsou?<\/p>\n

\u00a0<\/p>\n

\"Prav\u00e1\u017eka<\/a><\/p>\n

Prav\u00e1\u017eka versus dne\u0161n\u00ed v\u00e1\u017eka. Kredit: Estelle Mayhew, adapted from image by Aldrich Hezekiah.<\/p>\n

\u0158\u00edk\u00e1 se, \u017ee p\u0159ed 300 miliony let mohly l\u00e9tat v\u00e1\u017eky (p\u0159esn\u011bji \u0159e\u010deno prav\u00e1\u017eky s\u00a0kouzeln\u00fdm anglick\u00fdm jm\u00e9nem griffenflies, skupina Meganisoptera) s (t\u00e9m\u011b\u0159) metrov\u00fdm rozp\u011bt\u00edm k\u0159\u00eddel kv\u016fli tomu, \u017ee v\u00a0atmosf\u00e9\u0159e bylo zhruba o 45 procent v\u00edc kysl\u00edku ne\u017e dnes. Souvis\u00ed to s\u00a0difuz\u00ed kysl\u00edku v\u00a0syst\u00e9mu vzdu\u0161nic, kter\u00fdmi hmyz d\u00fdch\u00e1. V\u00a0dne\u0161n\u00ed dob\u011b je kysl\u00edku podstatn\u011b m\u00e9n\u011b a podle mainstreamov\u00fdch p\u0159edstav by to gigantick\u00fd hmyz neud\u00fdchal. Sou\u010dasn\u011b se ale tohle vysv\u011btlen\u00ed u\u017e dlouhou dobu zpochyb\u0148uje.<\/p>\n

\u00a0<\/p>\n

Mezin\u00e1rodn\u00ed v\u00fdzkumn\u00fd t\u00fdm, kter\u00fd vedl Edward Snelling z\u00a0jihoafrick\u00e9 University of Pretoria, vyu\u017eil elektronovou mikroskopii a prozkoumal upo\u0159\u00e1d\u00e1n\u00ed tracheol, koncov\u00fdch \u010d\u00e1st\u00ed soustavy vzdu\u0161nic, kter\u00e9 jako velice tenk\u00e9 trubi\u010dky vedou k\u00a0bu\u0148k\u00e1m, v\u00a0tomto p\u0159\u00edpad\u011b k\u00a0letov\u00fdm sval\u016fm hmyzu. Dosp\u011bli k\u00a0tomu, \u017ee tracheoly zab\u00edraj\u00ed v\u00a0letov\u00fdch svalech dne\u0161n\u00edho hmyzu zhruba 1 procento prostoru, co\u017e je \u00fapln\u011b stejn\u011b jako u prav\u00e1\u017eek jako byla Meganeura.<\/p>\n

Snelling a spol. z\u00a0toho vyvozuj\u00ed, \u017ee tam p\u0159\u00edrodn\u00ed v\u00fdb\u011br netla\u010dil na v\u011bt\u0161\u00ed dod\u00e1vky kysl\u00edku a \u017ee tud\u00ed\u017e obsah kysl\u00edku nebyl rozhoduj\u00edc\u00edm faktorem. Jin\u00ed v\u011bdci nam\u00edtaj\u00ed, \u017ee proud\u011bn\u00ed kysl\u00edku ve vzdu\u0161nic\u00edch stejn\u011b m\u016f\u017ee b\u00fdt limitem, kter\u00fd dnes omezuje velikost hmyzu. Anebo jsou d\u016fvody absence ob\u0159\u00edho hmyzu v\u00a0dne\u0161n\u00ed p\u0159\u00edrod\u011b \u00fapln\u011b jin\u00e9, t\u0159eba ekologick\u00e9 nebo biomechanick\u00e9. Ned\u00e1vn\u00e1 megafauna nezmizela kv\u016fli obsahu \u010dehosi v prost\u0159ed\u00ed, ale proto\u017ee ji sn\u011bdli lid\u00e9, p\u0159inejmen\u0161\u00edm ve v\u011bt\u0161in\u011b p\u0159\u00edpad\u016f. Z\u00e1hada ob\u0159\u00edho hmyzu ka\u017edop\u00e1dn\u011b pokra\u010duje.<\/p>\n

\u00a0<\/p>\n

Video: Meganeura – A Giant Carboniferous Griffenly<\/p>\n

\n

\u00a0<\/p>\n

Video: What Caused the Extinction of Giant Insects? | Full Documentary<\/p>\n

\n

\u00a0<\/p>\n

\u00a0<\/p>\n

Literatura<\/p>\n

Phys.org 25. 3. 2026.<\/a><\/p>\n

Nature online 25. 3. 2026.<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Na p\u0159elomu karbonu a permu, kdy\u017e doned\u00e1vna vlhk\u00fd tropick\u00fd sv\u011bt uheln\u00fdch ba\u017ein a prales\u016f vychladl, nad Pangeou l\u00e9tal…\n","protected":false},"author":2,"featured_media":39659,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[15914,1062,74,73,78,75,15913,77,76],"class_list":{"0":"post-39658","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-veda-a-technika","8":"tag-clenovec","9":"tag-robot","10":"tag-science","11":"tag-science-technology","12":"tag-technika","13":"tag-technology","14":"tag-vazka","15":"tag-veda","16":"tag-veda-a-technika"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@cz\/116315420257798337","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/posts\/39658","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/comments?post=39658"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/posts\/39658\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/media\/39659"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/media?parent=39658"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/categories?post=39658"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/cz\/wp-json\/wp\/v2\/tags?post=39658"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}