[{"@context":"https:\/\/schema.org\/","@type":"Article","@id":"https:\/\/www.graether.cz\/proc-dnes-jiz-neexistuje-obri-hmyz\/#Article","mainEntityOfPage":"https:\/\/www.graether.cz\/proc-dnes-jiz-neexistuje-obri-hmyz\/","headline":"Pro\u010d dnes ji\u017e neexistuje ob\u0159\u00ed hmyz","name":"Pro\u010d dnes ji\u017e neexistuje ob\u0159\u00ed hmyz","description":"Pokud se dnes \u0159ekne hmyz, v\u011bt\u0161ina z\u00a0n\u00e1s si p\u0159edstav\u00ed brouky, p\u0159\u00edpadn\u011b kom\u00e1ry \u010di dokonce v\u00e1\u017eky. Ti v\u0161ichni maj\u00ed jednu v\u011bc spole\u010dnou \u2013 malou velikost. Dnes nenajdeme \u017eivo\u010dicha z\u00a0t\u0159\u00eddy hmyzu, kter\u00fd by dosahoval skute\u010dn\u011b velk\u00fdch rozm\u011br\u016f. \u00a0 Tak tomu v\u0161ak nebylo v\u017edy. V\u00a0d\u00e1vn\u00fdch druhohor\u00e1ch a t\u0159etihor\u00e1ch se po na\u0161\u00ed planet\u011b proh\u00e1n\u011bly nap\u0159\u00edklad v\u00e1\u017eky s\u00a0a\u017e dvoumetrov\u00fdm rozp\u011bt\u00edm...","datePublished":"2023-01-12","dateModified":"2023-06-13","author":{"@type":"Person","@id":"https:\/\/www.graether.cz\/author\/#Person","name":"","url":"https:\/\/www.graether.cz\/author\/","identifier":1,"image":{"@type":"ImageObject","@id":"https:\/\/secure.gravatar.com\/avatar\/a1f3afbcba6a2c855138f9932fa7e5ab7d93bdcdef3da88e8b7e3a89881e43e8?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/a1f3afbcba6a2c855138f9932fa7e5ab7d93bdcdef3da88e8b7e3a89881e43e8?s=96&d=mm&r=g","height":96,"width":96}},"publisher":{"@type":"Organization","name":"graether.cz","logo":{"@type":"ImageObject","@id":"\/logo.png","url":"\/logo.png","width":600,"height":60}},"image":{"@type":"ImageObject","@id":"https:\/\/www.graether.cz\/wp-content\/uploads\/hmyz1.jpg","url":"https:\/\/www.graether.cz\/wp-content\/uploads\/hmyz1.jpg","height":0,"width":0},"url":"https:\/\/www.graether.cz\/proc-dnes-jiz-neexistuje-obri-hmyz\/","about":["V\u011bda"],"wordCount":442,"articleBody":"Pokud se dnes \u0159ekne hmyz, v\u011bt\u0161ina z\u00a0n\u00e1s si p\u0159edstav\u00ed brouky, p\u0159\u00edpadn\u011b kom\u00e1ry \u010di dokonce v\u00e1\u017eky. Ti v\u0161ichni maj\u00ed jednu v\u011bc spole\u010dnou \u2013 malou velikost. Dnes nenajdeme \u017eivo\u010dicha z\u00a0t\u0159\u00eddy hmyzu, kter\u00fd by dosahoval skute\u010dn\u011b velk\u00fdch rozm\u011br\u016f.\u00a0Tak tomu v\u0161ak nebylo v\u017edy. V\u00a0d\u00e1vn\u00fdch druhohor\u00e1ch a t\u0159etihor\u00e1ch se po na\u0161\u00ed planet\u011b proh\u00e1n\u011bly nap\u0159\u00edklad v\u00e1\u017eky s\u00a0a\u017e dvoumetrov\u00fdm rozp\u011bt\u00edm k\u0159\u00eddel. Ostatn\u00ed druhy hmyzu byly tak\u00e9 podstatn\u011b v\u011bt\u0161\u00ed, ne\u017e je zn\u00e1me dnes. Je tedy pochopiteln\u00e9, \u017ee se v\u011bdci zaj\u00edmali o to, co zp\u016fsobilo tuto redukci velikosti.\u00a0\u00a0Je jasn\u00e9, \u017ee to nemohla b\u00fdt potrava. Koneckonc\u016f, v\u00a0druhohor\u00e1ch \u017eili dinosau\u0159i, a n\u011bkte\u0159\u00ed z\u00a0nich dosahovali skute\u010dn\u011b ob\u0159\u00edch rozm\u011br\u016f. Tak\u00e9 sv\u011bteln\u00e9 \u010di teplotn\u00ed podm\u00ednky se p\u0159\u00edli\u0161 nezm\u011bnily. Jist\u011b, p\u0159i\u0161lo ochlazen\u00ed a doby ledov\u00e9, av\u0161ak v\u017edy existovaly tepl\u00e9 kraje, kam se mohl hmyz uch\u00fdlit. Co tedy st\u00e1lo za zmen\u0161en\u00edm velikosti hmyzu, zvl\u00e1\u0161t\u011b kdy\u017e savci se naopak zv\u011bt\u0161ili?\u00a0Odpov\u011b\u010f nab\u00edz\u00ed obsah kysl\u00edku v\u00a0atmosf\u00e9\u0159e. Ten byl toti\u017e v\u00a0dob\u011b, kdy zde poletoval a pochodoval ob\u0159\u00ed hmyz, mnohem vy\u0161\u0161\u00ed, ne\u017e jak\u00fd m\u00e1me dnes. Vy\u0161\u0161\u00ed obsah kysl\u00edku v\u00a0atmosf\u00e9\u0159e pak znamenal, \u017ee jej bylo mo\u017en\u00e9 vyu\u017e\u00edt v\u00edce pro svaly, kter\u00e9 si tak mohly dovolit b\u00fdt v\u011bt\u0161\u00ed. V\u00fdsledkem pak byly ob\u0159\u00ed rozm\u011bry. To je mimo jin\u00e9 tak\u00e9 to, co umo\u017enilo sauropod\u016fm dor\u016fstat ob\u0159\u00edch rozm\u011br\u016f.\u00a0\u00a0Postupn\u011b se v\u0161ak obsah kysl\u00edku sn\u00ed\u017eil na dne\u0161n\u00edch 21 %, kdy jej ji\u017e nen\u00ed dostatek k\u00a0tomu, aby mohly vzniknout v\u011bt\u0161\u00ed formy bezobratl\u00fdch. Ti se proto byli nuceni tomuto trendu p\u0159izp\u016fsobit t\u00edm, \u017ee se zmen\u0161ili.\u00a0To se samoz\u0159ejm\u011b nestalo najednou, byl to proces trvaj\u00edc\u00ed statist\u00edce let, kdy ty nejmen\u0161\u00ed exempl\u00e1\u0159e m\u011bly nejvy\u0161\u0161\u00ed \u0161anci na p\u0159e\u017eit\u00ed, a tento trend se pak v\u00a0dal\u0161\u00edch generac\u00edch opakoval. A jeliko\u017e velikost je vlastnost hodn\u011b d\u011bdi\u010dn\u00e1, je pochopiteln\u00e9, \u017ee tito mal\u00ed rodi\u010de plodili zase mal\u00e9 potomky. Z\u00a0nich op\u011bt p\u0159e\u017eili p\u0159edev\u0161\u00edm ti nejmen\u0161\u00ed, dokud jsme se nedostali na dne\u0161n\u00ed \u00farove\u0148.\u00a0Dnes je kysl\u00edk v\u00a0atmosf\u00e9\u0159e, nebo sp\u00ed\u0161 jeho objem, relativn\u011b stabiln\u00ed, tak\u017ee se \u017e\u00e1dn\u00e9 hromadn\u00e9 zm\u011bny ve velikostech jak\u00fdchkoliv \u017eivo\u010dich\u016f ned\u011bj\u00ed. Nikdo v\u0161ak nem\u016f\u017ee v\u011bd\u011bt, co p\u0159inese budoucnost.                                                                                                                                                                                                                                                                                                                                                                                        4\/5 - (8 votes)        "},{"@context":"https:\/\/schema.org\/","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Pro\u010d dnes ji\u017e neexistuje ob\u0159\u00ed hmyz","item":"https:\/\/www.graether.cz\/proc-dnes-jiz-neexistuje-obri-hmyz\/#breadcrumbitem"}]}]