{"id":2026,"date":"2024-02-10T00:57:45","date_gmt":"2024-02-09T23:57:45","guid":{"rendered":"https:\/\/www.zahadyazajimavosti.cz\/?p=2026"},"modified":"2024-02-23T03:06:44","modified_gmt":"2024-02-23T02:06:44","slug":"zahada-vyhynuti-dinosauru","status":"publish","type":"post","link":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/2024\/02\/10\/zahada-vyhynuti-dinosauru\/","title":{"rendered":"Z\u00e1hada vyhynut\u00ed dinosaur\u016f"},"content":{"rendered":"

Kdo jsou dinosau\u0159i?<\/strong><\/p>\n

Dinosau\u0159i \u017eili v obdob\u00ed druhohor, tedy asi p\u0159ed 245-265 miliony let.<\/p>\n

Jejich poz\u016fstatky z t\u00e9to doby nal\u00e9z\u00e1me na v\u0161ech kontinentech. Jak\u00e9si centrum dinosau\u0159\u00ed civilizace z\u0159ejm\u011b p\u0159edstavovala pou\u0161\u0165 Gobi, kde se na\u0161lo nejv\u00edce poz\u016fstatk\u016f, stejn\u011b jako prvn\u00ed zkamen\u011bl\u00e9 dinosau\u0159\u00ed vejce. Dnes n\u011bkte\u0159\u00ed badatel\u00e9 spekuluj\u00ed v\u0161ak i o tom, \u017ee ne v\u0161ichni dinosau\u0159i se l\u00edhli z vajec, n\u011bkte\u0159\u00ed pr\u00fd rodili \u017eiv\u00e1 ml\u00e1\u010fata jako dne\u0161n\u00ed savci. Dlouho se p\u0159edpokl\u00e1dalo, \u017ee dinosau\u0159i jako de facto plazi nedok\u00e1zali udr\u017eovat svoji t\u011blesnou teplotu, byli studenokrevn\u00ed. Av\u0161ak ned\u00e1vn\u00e9 v\u00fdzkumy paleontolog\u016f uk\u00e1zaly, \u017ee v\u011bt\u0161ina dinosaur\u016f byla teplokrevn\u00e1, a \u017ee obrovsk\u00e9 druhy ne\u017eily ve vod\u011b, jak se p\u016fvodn\u011b p\u0159edpokl\u00e1dalo. Nen\u00ed to tak\u00e9 tak dlouho, co paleontologov\u00e9 a biologov\u00e9 odhalili, jak bl\u00edzko m\u011bli dinosau\u0159i k dne\u0161n\u00edm pt\u00e1k\u016fm. Dlouho byli jako potomci prav\u011bk\u00fdch je\u0161t\u011br\u016f p\u0159edstavov\u00e1ni p\u0159edev\u0161\u00edm krokod\u00fdli, legu\u00e1ni, \u017eelvy a jin\u00ed plazi a je\u0161t\u011b\u0159i. Dnes u\u017e v\u00edme, \u017ee mnohem v\u00edce m\u011bli spole\u010dn\u00e9ho pr\u00e1v\u011b s pt\u00e1ky, kte\u0159\u00ed se dnes pova\u017euj\u00ed za v\u00fdvojov\u00e9 potomky dinosaur\u016f, dokonce se d\u00e1 \u0159\u00edci, \u017ee v podob\u011b pt\u00e1k\u016f dinosau\u0159i p\u0159e\u017eili sv\u016fj konec. N\u011bkter\u00e9 druhy dosahovaly obrovsk\u00fdch rozm\u011br\u016f a hmotnosti a\u017e 90 tun, jin\u00ed byli naopak drobn\u00ed jako kohout. Dinosau\u0159i byli p\u00e1ny planety, dominantn\u00edm druhem obratlovc\u016f dlouh\u00fdch 140 milion\u016f let (pro srovn\u00e1n\u00ed, Homo sapiens je na Zemi asi 3 miliony let).<\/p>\n

Drtiv\u00fd dopad<\/strong><\/p>\n

Existuj\u00ed v z\u00e1sad\u011b t\u0159i okruhy odpov\u011bd\u00ed na ot\u00e1zku, pro\u010d vlastn\u011b dinosau\u0159i vyhynuli.<\/p>\n

Historicky prvn\u00ed odpov\u011bd\u00ed bylo p\u0159esv\u011bd\u010den\u00ed, \u017ee dinosau\u0159i neunesli zm\u011bny v\u00fdvoje klimatu a sv\u00e9ho \u017eivotn\u00edho prost\u0159ed\u00ed. \u017de ztratili v\u00fdvojovou flexibilitu, pru\u017enost, p\u0159\u00edli\u0161 se na planet\u011b zabydleli. Takov\u00e1 p\u0159edstava je spojena s p\u0159esv\u011bd\u010den\u00edm, \u017ee vym\u00edrali pom\u011brn\u011b dlouhou dobu. Proti tomu v\u0161ak sv\u011bd\u010d\u00ed ji\u017e p\u0159\u00edli\u0161 mnoho indici\u00ed. P\u0159esto i dnes jsou n\u011bkte\u0159\u00ed v\u011bdci p\u0159esv\u011bd\u010deni, \u017ee maj\u00ed d\u016fkazy o tom, jak po\u010det dinosaur\u016f za\u010dal klesat ji\u017e sedm milion\u016f let p\u0159ed koncem k\u0159\u00eddy, s n\u00edm\u017e spojujeme i konec dinosaur\u016f. Dal\u0161\u00edm alternativn\u00edm vysv\u011btlen\u00edm je p\u0159edstava, \u017ee dinosau\u0159i vyhynuli v d\u016fsledku jak\u00e9si choroby \u010di epidemie. Jednu z nejpozoruhodn\u011bj\u0161\u00edch teori\u00ed zformuloval spisovatel Stanislaw Lem a my si ji p\u0159edstav\u00edme p\u0159\u00ed\u0161t\u011b.<\/p>\n

Dnes je v\u0161ak nejvlivn\u011bj\u0161\u00edm sm\u011brem v\u011bdeck\u00e9ho uva\u017eov\u00e1n\u00ed v ot\u00e1zce p\u00e1du dinosau\u0159\u00ed civilizace teorie dopadu t\u011blesa z kosmu na povrch Zem\u011b. Pro to sv\u011bd\u010d\u00ed \u0159ada indici\u00ed. Tak nap\u0159\u00edklad sou\u010dasn\u011b s dinosaury vyhynulo i mnoho jin\u00fdch suchozemsk\u00fdch a mo\u0159sk\u00fdch zv\u00ed\u0159at. Zhruba ve stejn\u00e9 dob\u011b zmizeli plesiosau\u0159i, mosasau\u0159i, ptakoje\u0161t\u011b\u0159i a tak\u00e9 hlavn\u00ed skupiny bezobratl\u00fdch. T\u011b\u017eko si p\u0159edstavit, \u017ee tak rozmanit\u00e1 populace \u017eivo\u010dich\u016f reagovala ve stejn\u00fd \u010das tak nep\u0159izp\u016fsobiv\u011b na b\u011b\u017en\u00e9 a dlouho trvaj\u00edc\u00ed klimatick\u00e9 zm\u011bny.<\/p>\n

Nejroz\u0161\u00ed\u0159en\u011bj\u0161\u00ed katastrofick\u00e1 teorie \u0159\u00edk\u00e1, \u017ee p\u0159ed p\u011bta\u0161edes\u00e1ti miliony let dopadl na Zemi asteroid o pr\u016fm\u011bru deseti kilometr\u016f, p\u0159i\u010dem\u017e jako nejpravd\u011bpodobn\u011bj\u0161\u00ed m\u00edsto dopadu asteroidu b\u00fdv\u00e1 ur\u010dov\u00e1n kr\u00e1ter na mexick\u00e9m poloostrov\u011b Yucatan. Kr\u00e1ter, kter\u00fd by po takov\u00e9m n\u00e1razu vznikl, by m\u011bl pr\u016fm\u011br asi dv\u011b stovky kilometr\u016f, a pr\u00e1v\u011b tyto parametry sed\u00ed na kr\u00e1ter Chicxulub ve zm\u00edn\u011bn\u00e9 oblasti. Prach, kter\u00fd by s\u00edla n\u00e1razu vymr\u0161tila do atmosf\u00e9ry, by zakryl na dlouhou dobu Slunce, rozbil sr\u00e1\u017ekov\u00fd \u0159\u00e1d a rychle vyhubil \u0159adu rostlinn\u00fdch, ale i \u017eivo\u010di\u0161n\u00fdch, zejm\u00e9na suchozemsk\u00fdch druh\u016f. Pro zast\u00e1nce t\u00e9to teorie je jedn\u00edm z d\u016fkaz\u016f geologick\u00e1 vrstva iridia, na Zemi velmi vz\u00e1cn\u00e9ho p\u0159etaven\u00e9ho a znovu ztvrdl\u00e9ho popela, kter\u00fd se ve zv\u00fd\u0161en\u00e9 koncentraci vyskytuje v asteroidech a meteoritech. Oponenti v\u0161ak nam\u00edtaj\u00ed: jak to, \u017ee n\u011bkter\u00e9 druhy zv\u00ed\u0159at p\u0159e\u017eily? Pro\u010d tato katastrofa tak zas\u00e1hla mo\u0159sk\u00e9 \u017eivo\u010dichy? Pro\u010d vyhynuli ptakoje\u0161t\u011b\u0159i, zat\u00edmco pt\u00e1ci p\u0159e\u017eili? Jakou m\u011bli v nukle\u00e1rn\u00ed zim\u011b v\u00fdhodu? A iridium mohlo b\u00fdt na povrch Zem\u011b vyneseno vulkanickou \u010dinnost\u00ed.<\/p>\n

Pr\u00e1v\u011b n\u00e1hl\u00e1 aktivita sope\u010dn\u00e9ho syst\u00e9mu je alternativn\u00ed verz\u00ed teorie kataklyzmatu: Sopky mohly do atmosf\u00e9ry n\u00e1hle uvolnit miliony tun oxidu si\u0159i\u010dit\u00e9ho. To by vyvolalo celosv\u011btov\u00e9 kysel\u00e9 de\u0161t\u011b, kter\u00e9 by zp\u016fsobily sn\u00ed\u017een\u00ed pH vody v oce\u00e1nech z hodnoty 8,2 a\u017e na 7,4. Rovn\u011b\u017e pr\u016fm\u011brn\u00e1 ro\u010dn\u00ed teplota by v d\u016fsledku toho klesla o 3,1 st. C. Do stratosf\u00e9ry by se dostala kyselina chlorovod\u00edkov\u00e1, kter\u00e1 by zeslabila ozonovou vrstvu. To by mohlo vysv\u011btlit zni\u010den\u00ed populace mo\u0159sk\u00e9ho planktonu a n\u00e1sledn\u011b i na planktonu z\u00e1visl\u00fdch vy\u0161\u0161\u00edch mo\u0159sk\u00fdch \u017eivo\u010dich\u016f. Mo\u017en\u00e1 \u017ee p\u0159e\u017e\u00edvaj\u00edc\u00ed obyvatel\u00e9 Zem\u011b by mohli m\u00edt se vzniklou ozonovou d\u00edrou stejn\u00e9 probl\u00e9my, jak\u00e9 dnes m\u00e1me my.<\/p>\n

Jen\u017ee posledn\u00ed v\u00fdzkumy hraj\u00ed do karet sp\u00ed\u0161e zast\u00e1nc\u016fm teorie asteroidu. T\u00fdm v\u00fdzkumn\u00edk\u016f veden\u00fd Dougem Robertsonem z Coloradsk\u00e9 univerzity ned\u00e1vno znovu podal nov\u00e9 d\u016fkazy o ni\u010div\u00e9m \u00fa\u010dinku dopadu planetky na povrch Zem\u011b p\u0159ed p\u011bta\u0161edes\u00e1ti miliony let. Robertson dokonce zavrhl tvrzen\u00ed, \u017ee hlavn\u00edm d\u016fvodem vym\u0159en\u00ed v\u011bt\u0161iny druh\u016f byla nukle\u00e1rn\u00ed zima zp\u016fsoben\u00e1 vzedmut\u00fdm prachem.<\/p>\n

Podle Robertsona byl konec dinosaur\u016f hektick\u00fd, jednalo se o z\u00e1le\u017eitost n\u011bkolika hodin \u010di dokonce minut. Obrovsk\u00e9 mno\u017estv\u00ed uvoln\u011bn\u00e9 energie prom\u011bnilo zemskou atmosf\u00e9ru v \u0161\u00edlenou vysokou pec, ve kter\u00e9 se v\u0161echny nechr\u00e1n\u011bn\u00e9 rostlinn\u00e9 i \u017eivo\u010di\u0161n\u00e9 druhy za kr\u00e1tkou dobu usma\u017eily. Organismy, kter\u00e9 byly naopak ukryty pod zem\u00ed \u010di pod vodou, byly p\u0159ed \u017e\u00e1rem uchr\u00e1n\u011bny a m\u011bly tak \u0161anci p\u00e1d asteroidu p\u0159e\u017e\u00edt. Tak snad p\u0159e\u017eili krokod\u00fdli, \u017eelvy i n\u011bkter\u00e9 druhy drobn\u00fdch savc\u016f. D\u016fkazem maj\u00ed b\u00fdt drobn\u00e9 kuli\u010dky p\u0159etaven\u00fdch hornin nal\u00e9zan\u00e9 po cel\u00e9m sv\u011bt\u011b, z\u0159ejm\u011b poz\u016fstatky gigantick\u00e9 ohniv\u00e9 bou\u0159e. Robertson na jejich z\u00e1klad\u011b spo\u010d\u00edtal energii prav\u011bk\u00e9ho v\u00fdbuchu na sto milion\u016f tun TNT. Hmota o obrovsk\u00e9 teplot\u011b byla vyvr\u017eena do stratosf\u00e9ry a p\u0159i n\u00e1vratu do atmosf\u00e9ry vytvo\u0159ila ohniv\u00e9 kladivo, kter\u00e9 ude\u0159ilo na zemsk\u00fd povrch. P\u0159i n\u00e1mitce, \u017ee tato teorie znovu nevysv\u011btluje genocidu pod mo\u0159skou hladinou, Robertson p\u0159iznal, \u017ee tu z\u0159ejm\u011b mohla zp\u016fsobit a\u017e n\u00e1sledn\u00e1 nukle\u00e1rn\u00ed zima a ochladnut\u00ed oce\u00e1nu v jej\u00edm d\u016fsledku.<\/p>\n

Jako na zavolanou pak ohl\u00e1sil v\u00fdsledky sv\u00e9ho b\u00e1d\u00e1n\u00ed italsko-americko-holandsk\u00fd t\u00fdm zkoumaj\u00edc\u00ed fosiln\u00ed z\u00e1znamy z oblasti El Kef v Tunisku. V chladn\u00fdch vod\u00e1ch jsou ulity mikroskopick\u00fdch tvor\u016f podobn\u00fdch hlem\u00fd\u017e\u010f\u016fm (Cibicidoides pseudoacutus) \u010dast\u011bji levoto\u010div\u00e9, kde\u017eto v tepl\u00fdch pravoto\u010div\u00e9. V geologick\u00fdch vrstv\u00e1ch z doby p\u0159ed dopadem planetky p\u0159evl\u00e1daj\u00ed pravoto\u010div\u00e9 ulity odpov\u00eddaj\u00edc\u00ed tepl\u00e9mu mo\u0159i. Po dopadu se ov\u0161em objevuje vy\u0161\u0161\u00ed koncentrace ulit levoto\u010div\u00fdch. Cosi radik\u00e1ln\u00edho se tedy p\u0159ed p\u011bta\u0161edes\u00e1ti miliony let stalo.<\/p>\n

Na co v\u0161ak Robertson ani jin\u00ed zat\u00edm nenal\u00e9zaj\u00ed odpov\u011b\u010f, jak cel\u00e9 zb\u011bsil\u00e9 kataklyzma p\u0159e\u017eili pt\u00e1ci, na rozd\u00edl od sv\u00fdch koleg\u016f ptakoje\u0161t\u011br\u016f. Pod zem \u010di do bahna se schovat nemohli. A tak, a\u017e v\u00e1m r\u00e1no za\u0165uk\u00e1 na parapet holub \u010di zazp\u00edv\u00e1 na zahrad\u011b kos, p\u0159ipome\u0148te si, \u017ee jde o jednu z nejv\u011bt\u0161\u00edch z\u00e1had na Zemi. A i sv\u00e9 ned\u011bln\u00ed ope\u010den\u00e9 ku\u0159\u00e1tko jezte s \u00factou, nebo\u0165 se pr\u00e1v\u011b \u017eiv\u00edte akt\u00e9rem jednoho z nejobdivuhodn\u011bj\u0161\u00edch a nejtajemn\u011bj\u0161\u00edch evolu\u010dn\u00edch v\u00fdkon\u016f, s n\u00edm\u017e se \u010dlov\u011bk dosud m\u016f\u017ee t\u011b\u017eko m\u011b\u0159it. Ten na svou velkou zkou\u0161ku ohn\u011bm teprve \u010dek\u00e1…<\/p>\n

Dinosau\u0159\u00ed AIDS<\/strong><\/p>\n

Se sv\u00e9r\u00e1znou a zaj\u00edmavou teori\u00ed o konci civilizace dinosaur\u016f p\u0159i\u0161el roku 1989 zn\u00e1m\u00fd autor sci-fi Stanislaw Lem.<\/p>\n

V kv\u011btnov\u00e9m \u010d\u00edsle sov\u011btsk\u00e9ho \u010dasopisu Priroda rozvinul spekulaci o tom, \u017ee by dinosau\u0159i mohli podlehnout \u010demusi, co by se dalo naz\u00fdvat dinosau\u0159\u00ed AIDS . Inspirac\u00ed pro formulov\u00e1n\u00ed takov\u00e9 teorie mu byl samoz\u0159ejm\u011b virus HIV, kter\u00fd pr\u00e1v\u011b v t\u00e9 dob\u011b za\u010d\u00ednal b\u00fdt t\u00e9matem \u0161ir\u0161\u00ed celospole\u010densk\u00e9 diskuse. Lem upozornil, \u017ee HIV je takzvan\u00fd retrovirus, kter\u00fd m\u00e1 specifickou evolu\u010dn\u00ed strategii, s n\u00ed\u017e se sna\u017e\u00ed ze sv\u00e9ho pohledu p\u0159e\u017e\u00edt a z pohledu napaden\u00e9 populace ji zahubit. Retrovirus se m\u016f\u017ee uplatnit jen u specifick\u00e9 populace. Lem upozornil, \u017ee \u010dlov\u011bk jako druh dosp\u011bl do f\u00e1ze, kdy bylo jen ot\u00e1zkou \u010dasu, kdy si ho n\u011bjak\u00fd retrovirus nalezne (nalezl si ho virus HIV) a z\u00e1rove\u0148 upozornil, \u017ee ve stejn\u00e9 situaci byli pravd\u011bpodobn\u011b p\u0159ed p\u011bta\u0161edes\u00e1ti miliony let pr\u00e1v\u011b dinosau\u0159i. Nevybaveni rozumem, kondomy a v\u011bdeck\u00fdm v\u00fdzkumem v\u0161ak museli front\u00e1ln\u00edmu \u00fatoku retroviru podlehnout, na rozd\u00edl od \u010dlov\u011bka, kter\u00fd si v\u00fd\u0161e uveden\u00fdm sna\u017e\u00ed sv\u016fj \u010das na planet\u011b prodlou\u017eit a boj se sv\u00fdm retrovirem nevzd\u00e1v\u00e1.<\/p>\n

Co vlastn\u011b onen nebezpe\u010dn\u00fd retrovirus pot\u0159ebuje, aby se rozvinul? Kl\u00ed\u010dov\u00e9 jsou t\u0159i p\u0159edpoklady. Za prv\u00e9 jde o to, aby se j\u00edm vyhl\u00e9dnut\u00e1 \u017eivo\u010di\u0161n\u00e1 populace rozmno\u017eovala pohlavn\u00edm zp\u016fsobem. Takov\u00e1 populace se p\u0159i objeven\u00ed viru \u0161\u00ed\u0159\u00edc\u00edho se pr\u00e1v\u011b pohlavn\u011b dost\u00e1v\u00e1 do naprost\u00e9 pasti. Kopulace jedinc\u016f opa\u010dn\u00e9ho pohlav\u00ed je jedin\u00fdm zp\u016fsobem, jak zachovat druhu p\u0159e\u017eit\u00ed, a p\u0159itom se ka\u017ed\u00fd takov\u00fd akt st\u00e1v\u00e1 potenci\u00e1ln\u00edm n\u00e1strojem viru pro jeho \u0161\u00ed\u0159en\u00ed. Aby v\u0161ak toto \u0161\u00ed\u0159en\u00ed m\u011blo n\u011bjak\u00fd smysl, nesm\u00ed virus zab\u00edjet hned. Mus\u00ed m\u00edt jistou f\u00e1zi latence, skryt\u00e9ho \u0161\u00ed\u0159en\u00ed a p\u016fsoben\u00ed. D\u0159\u00edve ne\u017e zah\u00e1j\u00ed na z\u00e1klad\u011b tajemn\u00e9ho impulzu tvrd\u00fd \u00fatok v\u016f\u010di napaden\u00e9 populaci, \u017eije v t\u011blech p\u0159\u00edslu\u0161n\u00edk\u016f druhu, ani\u017e by je n\u011bjak viditeln\u011b ohro\u017eoval.<\/p>\n

Tuto prvn\u00ed podm\u00ednku \u00fasp\u011b\u0161nosti strategie retroviru typu HIV mus\u00edme spr\u00e1vn\u011b pochopit. Pohlavn\u00edm zp\u016fsobem se pochopiteln\u011b rozmno\u017euj\u00ed v\u0161ichni savci. Zdaleka to v\u0161ak neznamen\u00e1, \u017ee v\u0161ichni savci jsou stejn\u011b ohro\u017eeni pandemi\u00ed n\u011bjak\u00e9ho retroviru typu HIV. V\u011bt\u0161ina savc\u016f toti\u017e \u017eije v hierarchick\u00fdch spole\u010denstv\u00edch a st\u00e1dech. Ka\u017ed\u00fd samec ve st\u00e1du nekopuluje s ka\u017edou samic\u00ed, proto\u017ee ve st\u00e1du panuj\u00ed pevn\u00e9 vztahy vz\u00e1jemn\u00e9 nad\u0159azenosti a pod\u0159\u00edzenosti. Samc\u016f, kte\u0159\u00ed sm\u011bj\u00ed oplod\u0148ovat samice, b\u00fdv\u00e1 velmi m\u00e1lo. Lem tvrd\u00ed, \u017ee jakousi mezn\u00ed hranic\u00ed je sto tis\u00edc dvoupohlavn\u00edch jedinc\u016f v populaci. Pokud j\u00ed druh dos\u00e1hne, splnil druhou podm\u00ednku pro p\u0159ipraven\u00ed p\u016fdy retroviru. Jen\u017ee to samo o sob\u011b nesta\u010d\u00ed.<\/p>\n

T\u0159et\u00ed podm\u00ednkou je, aby se populace na takov\u00e9 \u00farovni udr\u017eela n\u011bkolik milion\u016f let, \u010di je\u0161t\u011b l\u00e9pe, aby po tento \u010dasov\u00fd \u00fasek expandovala. Po takov\u00e9 dob\u011b toti\u017e doch\u00e1z\u00ed u populac\u00ed s p\u0159ekro\u010denou popula\u010dn\u00ed mez\u00ed k z\u00e1konit\u00e9 eliminaci hierarchick\u00fdch struktur. Nekopuluje u\u017e jen n\u011bkolik v\u00fdsadn\u00edch samc\u016f \u010di naopak samic, ale jak se \u0159\u00edk\u00e1, ka\u017ed\u00fd s ka\u017ed\u00fdm . Tato sexu\u00e1ln\u00ed demokratizace \u017eivo\u010di\u0161n\u00e9ho druhu je jak\u00fdmsi sign\u00e1lem retroviru dosud pokojn\u011b \u017eij\u00edc\u00edmu v t\u011blech sv\u00fdch hostitel\u016f k v\u00fdrob\u011b sv\u00e9ho zabij\u00e1ck\u00e9ho mutanta, kter\u00fd brzy zah\u00e1j\u00ed agresivn\u00ed \u00fatok. Zhruba t\u0159i miliony let vesele expanduj\u00edc\u00edmu \u010dlov\u011bku se to stalo v podob\u011b HIV. A Lem dovozuje: v\u017edy\u0165 dinosau\u0159i, alespo\u0148 m\u00e1me-li o nich spr\u00e1vnou p\u0159edstavu, splnili v\u0161echny t\u0159i p\u0159edpoklady. Ba dokonce, vyv\u00edjeli se o dobr\u00fdch sto \u010dty\u0159icet milion\u016f let d\u00e9le ne\u017e \u010dlov\u011bk. Mohli se setkat s jak\u00fdmsi velmi agresivn\u00edm a po miliony let na \u00fatok se p\u0159ipravuj\u00edc\u00edm retrovirem, zp\u016fsobuj\u00edc\u00edm dinosau\u0159\u00ed AIDS ?<\/p>\n

Lem, a\u010dkoli profesion\u00e1ln\u00edm fantastou, samoz\u0159ejm\u011b stoj\u00ed pevn\u011b na zemi a zn\u00e1 logick\u00e9 n\u00e1mitky: viry se v\u011bt\u0161inou vyzna\u010duj\u00ed p\u0159esn\u00fdm druhov\u00fdm zac\u00edlen\u00edm p\u0159i v\u00fdb\u011bru sv\u00e9ho hostitele. Dinosau\u0159i p\u0159edstavovali pestrou \u0161k\u00e1lu r\u016fzn\u00fdch variant, kter\u00e9 se pravd\u011bpodobn\u011b dosti geneticky li\u0161ily (a\u010dkoli to nev\u00edme jist\u011b), asi jako se li\u0161\u00ed r\u016fzn\u00e9 druhy savc\u016f, a je m\u00e1lo pravd\u011bpodobn\u00e9, \u017ee by jedna konkr\u00e9tn\u00ed mutace viru mohla zas\u00e1hnout tak rozd\u00edln\u00e9 \u017eivo\u010dichy. Na druhou stranu m\u011bl potenci\u00e1ln\u00ed dinosau\u0159\u00ed HIV mnohem v\u00edce \u010dasu na sv\u016fj rozvoj ne\u017e ten lidsk\u00fd. A o muta\u010dn\u00ed schopnosti vir\u016f a jejich nesm\u00edrn\u00e9 n\u00e1paditosti za\u010d\u00edn\u00e1me cosi tu\u0161it a\u017e v posledn\u00edch letech.<\/p>\n

Jist\u00e9 je, \u017ee pokud by dinosaur\u016fm skute\u010dn\u011b vyhl\u00e1sil v\u00e1lku virus typu HIV, nem\u011bli by \u0161anci a b\u011bhem velmi kr\u00e1tk\u00e9 doby by vyhynuli. Nejen proto, \u017ee nem\u011bli kondomy. Probl\u00e9m toti\u017e je, \u017ee kdy\u017e u\u017e zabij\u00e1ck\u00e1 mutace viru za\u00fato\u010d\u00ed, tak jako to ud\u011blal HIV, m\u00e1 \u017eivo\u010di\u0161n\u00fd druh stra\u0161n\u011b m\u00e1lo \u010dasu naj\u00edt \u0159e\u0161en\u00ed evolu\u010dn\u00ed. Teoreticky by samoz\u0159ejm\u011b existovalo: nap\u0159\u00edklad hmyz ji\u017e po miliony let popula\u010dn\u011b expanduje doslova zb\u011bsile. Hrozbu retroviru vy\u0159e\u0161il nad\u0159azen\u00edm soci\u00e1ln\u00ed kooperace. Mravenci, v\u010dely, termiti \u010di vosy se sdru\u017euj\u00ed do bezpohlavn\u00edch spole\u010denstv\u00ed. Pro\u010d vlastn\u011b ta \u010dlov\u011bku tak nepochopiteln\u00e1 asexu\u00e1lnost t\u011bchto druh\u016f? V\u017edy\u0165 jsou to tak\u00e9 druhy pohlavn\u011b rozd\u011blen\u00e9 na samce a sami\u010dky. Pro\u010d u jedinc\u016f t\u011bchto druh\u016f nezv\u00edt\u011bzila individu\u00e1ln\u00ed touha \u0161\u00ed\u0159it svou genetickou informaci? Pro\u010d se natolik pod\u0159\u00eddili dikt\u00e1tu roje \u010di termiti\u0161t\u011b , kde pln\u00ed rozmno\u017eovac\u00ed funkci jen jeden jedinec, samice-kr\u00e1lovna, kter\u00e1 je oplodn\u011bna v\u011bt\u0161inou b\u011bhem jedin\u00e9ho aktu?<\/p>\n

Podobn\u00e9 ot\u00e1zky nejsou v\u016fbec nesmysln\u00e9. Takov\u00e9 druhy hmyzu p\u0159i sv\u00e9 expanzivn\u00ed popula\u010dn\u00ed politice by se toti\u017e p\u0159i sv\u00e9 potenci\u00e1ln\u00ed sexu\u00e1ln\u00ed revoluci a emancipaci sexuchtiv\u00fdch jedinc\u016f musely d\u0159\u00edve \u010di pozd\u011bji utkat s retrovirem a t\u011b\u017ece by tento boj prohr\u00e1ly. Mo\u017en\u00e1 se takov\u00e1 dramata dokonce v d\u011bjin\u00e1ch \u0159\u00e1du hmyzu i odehr\u00e1la. Mo\u017en\u00e1, \u017ee toto drama zahubilo i dinosaury.<\/p>\n

\u010clov\u011bk zat\u00edm hled\u00e1 \u0159e\u0161en\u00ed \u00fat\u011bkem od p\u0159\u00edrody ke kultu\u0159e. P\u0159irozenou odpov\u011bd\u00ed na n\u00e1stup retroviru by byl p\u0159echod k n\u011bjak\u00e9 kooperativn\u011bj\u0161\u00ed evolu\u010dn\u00ed strategii, k n\u00ed\u017e by v\u0161ak na\u0161e t\u011bla pot\u0159ebovala statis\u00edce let \u010dasu. Kulturn\u00edm \u0159e\u0161en\u00edm jsou odpov\u011bdnost a prost\u0159edky typu kondom. A pak tu jsou samoz\u0159ejm\u011b \u0159e\u0161en\u00ed hybridn\u00ed: kulturn\u011b-biologick\u00e1 \u010di biologicko-kulturn\u00ed. To druh\u00e9, jak\u00e1si eugenika, p\u0159enesen\u00ed \u00fakolu formov\u00e1n\u00ed populace na bedra genetick\u00fdch program\u00e1tor\u016f, by bylo velkou prohrou a hrozbou, na jej\u00edm\u017e konci by proti sob\u011b st\u00e1li geneti\u010dt\u00ed vyvolenci a chud\u00fd genetick\u00fd odpad z periferie. Prvn\u00ed \u0159e\u0161en\u00ed by bylo naopak velkou v\u00fdhrou. Spo\u010d\u00edvalo by v p\u0159ijet\u00ed jak\u00e9hosi programu glob\u00e1ln\u00ed biologick\u00e9 odpov\u011bdnosti. Do n\u011bho by jist\u011b pat\u0159ily takov\u00e9 kroky, jak\u00e9 u\u010dinila v minul\u00e9m stolet\u00ed \u010d\u00ednsk\u00e1 vl\u00e1da projektem regulace porodnosti. To by v\u0161ak nesm\u011bly na na\u0161\u00ed planet\u011b p\u016fsobit mocn\u00e9 agentury na v\u00fdrobu bohulib\u00e9 mor\u00e1lky. Sv\u00fdmi pseudohumanistick\u00fdmi idejemi odvozen\u00fdmi z antikvari\u00e1tn\u00edch text\u016f zformulovan\u00fdch pro zcela jin\u00e9 spole\u010densk\u00e9 pot\u0159eby tak stoj\u00ed na stran\u011b retroviru, na stran\u011b nejzan\u00edcen\u011bj\u0161\u00edch nep\u0159\u00e1tel lidsk\u00e9ho rodu, na stran\u011b smrti, a\u010dkoli se p\u0159i sv\u00fdch vlivn\u00fdch kampan\u00edch neust\u00e1le oh\u00e1n\u011bj\u00ed slovem \u017eivot ve v\u0161ech jeho p\u00e1dech.<\/p>\n

Jan Stern<\/em><\/p>\n

Z archivu KPUFO<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Kdo jsou dinosau\u0159i?<\/p>\n","protected":false},"author":1,"featured_media":675,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[19],"tags":[41,35,29],"class_list":["post-2026","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-zahady","tag-archeologie","tag-kryptozoologie","tag-zivocichove"],"_links":{"self":[{"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/posts\/2026","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/comments?post=2026"}],"version-history":[{"count":3,"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/posts\/2026\/revisions"}],"predecessor-version":[{"id":2032,"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/posts\/2026\/revisions\/2032"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/media\/675"}],"wp:attachment":[{"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/media?parent=2026"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/categories?post=2026"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zahadyazajimavosti.cz\/index.php\/wp-json\/wp\/v2\/tags?post=2026"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}