{"id":14124,"date":"2020-08-25T02:35:48","date_gmt":"2020-08-25T02:35:48","guid":{"rendered":"https:\/\/www.lifescienceart.com\/?p=14124"},"modified":"2020-08-25T02:35:48","modified_gmt":"2020-08-25T02:35:48","slug":"expressive-eyebrows-evolutionary-edge-modern-humans","status":"publish","type":"post","link":"https:\/\/www.lifescienceart.com\/cs\/science\/human-evolution\/expressive-eyebrows-evolutionary-edge-modern-humans\/","title":{"rendered":"V\u00fdrazn\u00e9 obo\u010d\u00ed: evolu\u010dn\u00ed v\u00fdhoda modern\u00edch lid\u00ed"},"content":{"rendered":"

V\u00fdrazn\u00e9 obo\u010d\u00ed: Evolu\u010dn\u00ed v\u00fdhoda modern\u00edch lid\u00ed<\/h2>\n\n

Evoluce nado\u010dnicov\u00fdch oblouk\u016f<\/h2>\n\n

D\u00e1vn\u00ed lid\u00e9 m\u011bli v\u00fdrazn\u00e9 nado\u010dnicov\u00e9 oblouky, v\u00fdrazn\u00fd rys, kter\u00fd v\u011bdce po desetilet\u00ed m\u00e1t. V\u00fdzkumn\u00edci navrhli r\u016fzn\u00e9 teorie, aby vysv\u011btlili jejich \u00fa\u010del, v\u010detn\u011b ochrany p\u0159ed poran\u011bn\u00edm hlavy, st\u00edn\u011bn\u00ed o\u010d\u00ed a prevence p\u0159ek\u00e1\u017een\u00ed vlas\u016f. Ned\u00e1vn\u00e9 studie v\u0161ak tyto tradi\u010dn\u00ed v\u00fdklady zpochybnily.<\/p>\n\n

Hypot\u00e9za soci\u00e1ln\u00ed funkce<\/h2>\n\n

T\u00fdm v\u00fdzkumn\u00edk\u016f na University of York v Anglii zkoumal hypot\u00e9zu soci\u00e1ln\u00ed funkce, kter\u00e1 nazna\u010duje, \u017ee nadm\u011brn\u011b velk\u00e9 nado\u010dnicov\u00e9 oblouky slou\u017eily jako sign\u00e1l dominance. Teoretizovali, \u017ee tyto h\u0159ebeny vy\u010dn\u00edvaly, aby vytvo\u0159ily impozantn\u011bj\u0161\u00ed vzhled, odrazovaly potenci\u00e1ln\u00ed hrozby a p\u0159ed\u00e1valy status uvnit\u0159 soci\u00e1ln\u00edch skupin.<\/p>\n\n

Mechanick\u00e9 nam\u00e1h\u00e1n\u00ed a obli\u010dejov\u00e1 anatomie<\/h2>\n\n

Aby tuto hypot\u00e9zu otestovali, vytvo\u0159ili v\u00fdzkumn\u00edci 3D model d\u00e1vn\u00e9 lidsk\u00e9 lebky a experimentovali s velikost\u00ed nado\u010dnicov\u00e9ho oblouku. Zjistili, \u017ee zmen\u0161en\u00ed velikosti h\u0159ebene nevedlo k v\u00fdrazn\u00e9mu sn\u00ed\u017een\u00ed mechanick\u00e9ho nam\u00e1h\u00e1n\u00ed lebky p\u0159i kous\u00e1n\u00ed. Nav\u00edc byl oblouk v\u011bt\u0161\u00ed, ne\u017e bylo nutn\u00e9 k vypln\u011bn\u00ed mezery mezi \u010delem a o\u010dn\u00edmi d\u016flky.<\/p>\n\n

Behavior\u00e1ln\u00ed pozorov\u00e1n\u00ed<\/h2>\n\n

Antropolog Grover Krantz provedl experiment, kdy na ve\u0159ejnosti nosil repliku nado\u010dnicov\u00e9ho oblouku Homo erectus. Pozoroval, \u017ee se mu lid\u00e9 tenden\u010dn\u011b vyh\u00fdbali, co\u017e nazna\u010duje, \u017ee nado\u010dnicov\u00fd oblouk mohl vyvol\u00e1vat pocit zastra\u0161en\u00ed. Toto pozorov\u00e1n\u00ed d\u00e1le podpo\u0159ilo hypot\u00e9zu soci\u00e1ln\u00ed funkce.<\/p>\n\n

Zmen\u0161ov\u00e1n\u00ed obli\u010deje a soci\u00e1ln\u00ed komunikace<\/h2>\n\n

Postupem \u010dasu se lidsk\u00e9 tv\u00e1\u0159e za\u010daly zmen\u0161ovat, mo\u017en\u00e1 kv\u016fli pokroku ve zp\u016fsobech va\u0159en\u00ed nebo zm\u011bn\u00e1m v \u00farovni aktivity. Jak se obli\u010deje zmen\u0161ovaly, na\u0161i p\u0159edkov\u00e9 se st\u00e1vali spole\u010dens\u0161t\u011bj\u0161\u00edmi, se zv\u00fd\u0161en\u00fdm kontaktem a spoluprac\u00ed mezi skupinami. V\u00fdzkumn\u00edci se domn\u00edvaj\u00ed, \u017ee ztr\u00e1ta nado\u010dnicov\u00fdch oblouk\u016f usnadnila jemn\u011bj\u0161\u00ed emocion\u00e1ln\u00ed v\u00fdrazy, co\u017e zlep\u0161ilo komunikaci a spolupr\u00e1ci.<\/p>\n\n

Pohybliv\u00e9 obo\u010d\u00ed a jemn\u00e1 signalizace<\/h2>\n\n

Modern\u00ed lid\u00e9 maj\u00ed pohybliv\u00e9 obo\u010d\u00ed, kter\u00e9 je velmi v\u00fdrazn\u00e9 a z\u00e1sadn\u00ed pro vyj\u00e1d\u0159en\u00ed jemn\u00fdch emoc\u00ed. Bez omezen\u00ed v\u00fdrazn\u00e9ho nado\u010dnicov\u00e9ho m\u016fstku m\u016f\u017ee na\u0161e obo\u010d\u00ed vyjad\u0159ovat \u0161irokou \u0161k\u00e1lu pozitivn\u00edch emoc\u00ed, jako je p\u0159ekvapen\u00ed, skepse a zmatek.<\/p>\n\n

Odborn\u00e9 pohledy<\/h2>\n\n

Zat\u00edmco hypot\u00e9za soci\u00e1ln\u00ed funkce z\u00edsk\u00e1v\u00e1 na s\u00edle, n\u011bkte\u0159\u00ed odborn\u00edci z\u016fst\u00e1vaj\u00ed skepti\u010dt\u00ed. Paleoantropolo\u017eka Ashley Hammondov\u00e1 tvrd\u00ed, \u017ee siln\u00e9 nado\u010dnicov\u00e9 kosti Homo heidelbergensis mohly b\u00fdt zp\u016fsobeny vy\u0161\u0161\u00ed hladinou testosteronu. Nov\u00fd v\u00fdzkum v\u0161ak dopl\u0148uje st\u00e1le v\u011bt\u0161\u00ed mno\u017estv\u00ed d\u016fkaz\u016f, \u017ee komunikace a spolupr\u00e1ce byly \u017eivotn\u011b d\u016fle\u017eit\u00e9 pro p\u0159e\u017eit\u00ed na\u0161eho druhu.<\/p>\n\n

Implikace pro lidskou evoluci<\/h2>\n\n

Studium nado\u010dnicov\u00fdch oblouk\u016f poskytuje poznatky o v\u00fdvoji lidsk\u00e9 komunikace a soci\u00e1ln\u00edho chov\u00e1n\u00ed. Zd\u016fraz\u0148uje vz\u00e1jemn\u00e9 p\u016fsoben\u00ed mezi fyzickou anatomi\u00ed a soci\u00e1ln\u00ed dynamikou, co\u017e nazna\u010duje, \u017ee na\u0161e v\u00fdrazn\u00e9 obo\u010d\u00ed mohlo hr\u00e1t v\u00fdznamnou roli v \u00fasp\u011bchu modern\u00edch lid\u00ed.<\/p>","protected":false},"excerpt":{"rendered":"

V\u00fdrazn\u00e9 obo\u010d\u00ed: Evolu\u010dn\u00ed v\u00fdhoda modern\u00edch lid\u00ed Evoluce nado\u010dnicov\u00fdch oblouk\u016f D\u00e1vn\u00ed lid\u00e9 m\u011bli v\u00fdrazn\u00e9 nado\u010dnicov\u00e9 oblouky, v\u00fdrazn\u00fd rys, kter\u00fd v\u011bdce po desetilet\u00ed m\u00e1t. V\u00fdzkumn\u00edci navrhli r\u016fzn\u00e9 teorie, aby vysv\u011btlili jejich \u00fa\u010del,…<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[19000],"tags":[136,18052,18998,18999,7210],"class_list":["post-14124","post","type-post","status-publish","format-standard","hentry","category-human-evolution","tag-evolution","tag-human-anatomy","tag-eyebrows","tag-social-communication","tag-cooperation"],"_links":{"self":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts\/14124","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/comments?post=14124"}],"version-history":[{"count":1,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts\/14124\/revisions"}],"predecessor-version":[{"id":14125,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/posts\/14124\/revisions\/14125"}],"wp:attachment":[{"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/media?parent=14124"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/categories?post=14124"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifescienceart.com\/cs\/wp-json\/wp\/v2\/tags?post=14124"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}