Mokslininkai paskelb\u0117 reik\u0161ming\u0105 prover\u017e\u012f tiriant paslapting\u0105 i\u0161nykus\u012f \u017emoni\u0173 gimin\u0117s atstov\u0105 Homo naledi. U\u017euot ie\u0161koj\u0119 DNR, kuri \u0161iltame Afrikos klimate greitai suyra, tyr\u0117jai i\u0161 dant\u0173 emalio i\u0161gavo ir i\u0161analizavo itin senus baltymus.<\/p>\n
Analiz\u0117 atlikta 23 dantims, priklausiusiems ma\u017eiausiai 20 individ\u0173. Tokie baltymai gali i\u0161likti \u0161imtus t\u016bkstan\u010di\u0173 ar net milijonus met\u0173, tod\u0117l jie tampa alternatyva ten, kur genetin\u0117 med\u017eiaga prakti\u0161kai nebei\u0161saugoma.<\/p>\n
Did\u017eiausia intriga kilo tiriant amelogenin\u0105 \u2013 dant\u0173 emalio baltym\u0105, turint\u012f formas, siejamas su X ir Y chromosomomis. Tyr\u0117jai nurod\u0117, kad n\u0117 viename tirtame m\u0117ginyje nepavyko aptikti Y chromosomai b\u016bdingo varianto.<\/p>\n
Remiantis \u0161iuo po\u017eymiu, visi i\u0161tirti individai grei\u010diausiai buvo biologi\u0161kai moteri\u0161kos lyties. Paleoantropologams tai tapo netik\u0117tu rezultatu, nes iki \u0161iol buvo manoma, kad radiniai tur\u0117t\u0173 atspind\u0117ti mi\u0161ri\u0105 populiacij\u0105.<\/p>\n
Homo naledi kaulai buvo aptikti Piet\u0173 Afrikoje, Rising Star urv\u0173 sistemoje, giliai ir sunkiai pasiekiamoje kameroje. Nuo 2013 metais paskelbto atradimo dalis tyr\u0117j\u0173 k\u0117l\u0117 hipotez\u0119, kad k\u016bnai gal\u0117jo b\u016bti s\u0105moningai pad\u0117ti urve, o tai reik\u0161t\u0173 sud\u0117tingesn\u012f socialin\u012f elges\u012f, nei b\u016bt\u0173 tik\u0117tasi turint omenyje ma\u017eesn\u0119 \u0161ios r\u016b\u0161ies smegen\u0173 apimt\u012f.<\/p>\n
Jei vis d\u0117lto kameroje i\u0161 ties\u0173 atsid\u016br\u0117 tik vienos lyties individai, atsiranda naujas paai\u0161kinimas: vieta gal\u0117jo tur\u0117ti specifin\u0119 paskirt\u012f, susijusi\u0105 su i\u0161skirtinai vienos lyties laidojimo ar kitomis ritualizuotomis praktikomis. Vis d\u0117lto autoriai pabr\u0117\u017eia, kad tai i\u0161lieka hipoteze.<\/p>\n
Alternatyvus paai\u0161kinimas taip pat neatmetamas: Y chromosomos po\u017eymio nebuvimas gal\u0117jo b\u016bti susij\u0119s su iki \u0161iol ne\u017einomu \u0161ios r\u016b\u0161ies genetiniu ypatumu, o ne su realia tirt\u0173 individ\u0173 lyties strukt\u016bra. Tokiu atveju vien baltymo \u017eymen\u0173 dar nepakakt\u0173 galutinei i\u0161vadai.<\/p>\n
Tyrimas pateik\u0117 ir papildom\u0173 u\u017euomin\u0173 apie evoliucinius ry\u0161ius. Baltym\u0173 duomenys parod\u0117 kolageno gamybai svarbaus geno variant\u0105, kur\u012f Homo naledi dalijosi su Paranthropus robustus \u2013 kitu i\u0161nykusiu homininu, gyvenusiu Afrikoje daugiau nei prie\u0161 1 milijon\u0105 met\u0173.<\/p>\n
Tokie sutapimai gali pad\u0117ti tikslinti sen\u0173j\u0173 hominin\u0173 giminyst\u0117s schemas, ypa\u010d kai tr\u016bksta DNR. Ta\u010diau mokslininkai pripa\u017e\u012fsta, kad vien bendr\u0173 baltym\u0173 \u017eymen\u0173 nepakanka tiksliai nustatyti, k\u0105 \u0161i bendra savyb\u0117 rei\u0161k\u0117 prisitaikymo ir evoliucijos po\u017ei\u016briu.<\/p>\n
Tyr\u0117jai pabr\u0117\u017eia, kad itin sen\u0173 baltym\u0173 analiz\u0117 tampa vis svarbesne paleontologijos kryptimi. Ji leid\u017eia nustatyti giminyst\u0117s po\u017eymius, kai kurias genetines ypatybes ir tik\u0117tin\u0105 biologin\u0119 lyt\u012f net tuomet, kai pilno genomo atkurti ne\u012fmanoma.<\/p>\n
\u0160is darbas publikuotas mokslo \u017eurnale Cell ir laikomas vienu ry\u0161kesni\u0173 pavyzd\u017ei\u0173, kaip proteomika ple\u010dia sen\u0173j\u0173 \u017emoni\u0173 ir j\u0173 giminai\u010di\u0173 tyrim\u0173 ribas. Kartu jis primena, kad sensacingos i\u0161vados apie elgsen\u0105 ar laidojimo papro\u010dius turi b\u016bti vertinamos atsargiai, kol j\u0173 nepatvirtina papildomi duomenys.<\/p>\n","protected":false},"excerpt":{"rendered":"
Mokslininkai i\u0161 23 Homo naledi dant\u0173 emalio i\u0161gavo 300 000 met\u0173 baltymus, o rezultatai netik\u0117tai pakeit\u0117 sp\u0117liones apie urvo radinius.<\/p>\n","protected":false},"author":0,"featured_media":37399,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[10],"tags":[12450,28835,7151,6193,10858,28836],"miestas":[],"class_list":["post-37398","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mokslas","tag-dantu-emalis","tag-homo-naledi","tag-paleoantropologija","tag-pietu-afrika","tag-proteomika","tag-rising-star-urvai"],"acf":[],"_links":{"self":[{"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/posts\/37398","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/comments?post=37398"}],"version-history":[{"count":0,"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/posts\/37398\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/media\/37399"}],"wp:attachment":[{"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/media?parent=37398"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/categories?post=37398"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/tags?post=37398"},{"taxonomy":"miestas","embeddable":true,"href":"https:\/\/cp.snarskis.lt\/index.php\/wp-json\/wp\/v2\/miestas?post=37398"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}