{"id":10461,"date":"2011-04-01T20:40:42","date_gmt":"2011-04-01T17:40:42","guid":{"rendered":"http:\/\/109.232.216.219\/~bilimvegelecek\/?p=10461"},"modified":"2017-05-26T20:44:34","modified_gmt":"2017-05-26T17:44:34","slug":"modern-insan-ile-neanderthal-beyni-farkli-gelisti","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2011\/04\/01\/modern-insan-ile-neanderthal-beyni-farkli-gelisti","title":{"rendered":"Modern insan ile Neanderthal beyni farkl\u0131 geli\u015fti"},"content":{"rendered":"
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Modern insan (solda) ve Neahderthal beyinleri<\/figcaption><\/figure>\n

Modern insan ile Neanderthal aras\u0131nda bili\u015fsel fark olup olmamas\u0131, antropolojide ve arkeolojide tart\u0131\u015fmal\u0131 bir konudur. \u00c7\u00fcnk\u00fc bir\u00e7ok ara\u015ft\u0131rmac\u0131, modern insan ve Neanderthal beyin \u00f6l\u00e7\u00fcs\u00fc kar\u015f\u0131la\u015ft\u0131r\u0131ld\u0131\u011f\u0131nda, \u00f6nceleri bu iki t\u00fcr\u00fcn bili\u015fsel yeteneklerinin benzer oldu\u011funu d\u00fc\u015f\u00fcnd\u00fcler. Ancak beynin i\u00e7 d\u00fczenlenmesi bili\u015fsel yetenekler i\u00e7in kendi net hacminden daha \u00f6nemlidir. Beynin i\u00e7 d\u00fczeni, beyin geli\u015fiminin bi\u00e7im ve temposuna ba\u011fl\u0131d\u0131r.<\/p>\n

Max Planck Enstit\u00fcs\u00fc\u2019nde (MPI) \u00e7al\u0131\u015fan bir grup bilim insan\u0131, b\u00fcy\u00fcme s\u00fcreci boyunca kafatas\u0131n\u0131n i\u00e7 \u015fekil de\u011fi\u015fikliklerinin detayl\u0131 \u00f6l\u00e7\u00fcm\u00fcne dayanarak, bili\u015fsel geli\u015fimin kritik a\u015famalar\u0131nda iki t\u00fcr aras\u0131ndaki beyin geli\u015fim deseninin farkl\u0131 oldu\u011funu g\u00f6sterdi.<\/p>\n

\u0130nsan fosillerinin bili\u015fsel yetenekleri \u00fczerine yap\u0131lan tart\u0131\u015fmalar \u00e7o\u011funlukla k\u00fclt\u00fcrel materyallere (\u00f6r: karma\u015f\u0131k ta\u015f aletin yap\u0131m\u0131) ve kafatas\u0131n\u0131n i\u00e7 hacmine odaklan\u0131r. MPI-EVA\u2019da \u0130nsan Evrimi Departman\u0131\u2019n\u0131n m\u00fcd\u00fcr\u00fc Jean-Jacques Hublin, arkeolojik kan\u0131tlar\u0131n yorumunun tart\u0131\u015fmal\u0131 oldu\u011funu, modern insan ve Neanderthal beyin \u00f6l\u00e7\u00fcmlerinin \u00e7ak\u0131\u015ft\u0131\u011f\u0131n\u0131 s\u00f6yl\u00fcyor ve ekliyor: \u201cBizim bulgular\u0131m\u0131z iki t\u00fcr aras\u0131ndaki biyolojik fark\u0131n, arkeolojik kay\u0131tlardan anla\u015f\u0131lan davran\u0131\u015fsal farklara ba\u011fl\u0131 oldu\u011funu g\u00f6steriyor.\u201d<\/p>\n

Beynimiz fosille\u015fmez. Ancak beynimizin kemikte b\u0131rakt\u0131\u011f\u0131 iz \u00e7al\u0131\u015f\u0131labilir. Ara\u015ft\u0131rmac\u0131lar, tomografik taramadan \u00e7\u0131kan sanal kemik izi \u015fekil de\u011fi\u015fimlerini kar\u015f\u0131la\u015ft\u0131rmak i\u00e7in baz\u0131 istatistiksel y\u00f6ntemleri kulland\u0131. Homo sapiens\u2019in kafatas\u0131n\u0131n belirgin k\u00fcresel \u015fekli, b\u00fcy\u00fck oranda, Neanderthal\u2019de g\u00f6r\u00fclmeyen beyin geli\u015fimi a\u015famalar\u0131n\u0131n sonucudur.<\/p>\n

Kilit kan\u0131tlardan biri, yeni do\u011fmu\u015f bir Neanderthal\u2019in \u00e7\u0131kar\u0131lm\u0131\u015f kafatas\u0131yd\u0131. 1914\u2019te bir Frans\u0131z arkeolog grubu, Dordogne\u2019daki Le Moustier kayal\u0131klar\u0131nda bir Neanderthal bebek iskeleti bulmu\u015ftu. Bug\u00fcn Les Eyzies-de-Tayac-Sireuil Ulusal M\u00fczesi\u2019nde bulunan fosil, Max Planck Enstit\u00fcs\u00fc\u2019nde y\u00fcksek \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc tomografi taray\u0131c\u0131s\u0131nda tarand\u0131. Ard\u0131ndan Philipp Gunz, Simon Neubauer isimli ara\u015ft\u0131rmac\u0131lar, t\u0131pk\u0131 \u00fc\u00e7 boyutlu bir yapboz gibi eldeki dijital par\u00e7alardan Neanderthal bebe\u011fini yeniden in\u015fa ettiler.<\/p>\n

Gunz \u201cYeni do\u011fan bir modern insan ile bir neanderthal kafatas\u0131n\u0131 kar\u015f\u0131la\u015ft\u0131rd\u0131\u011f\u0131m\u0131zda Neanderthal\u2019in y\u00fcz\u00fc do\u011fumda daha b\u00fcy\u00fckt\u00fcr. Fakat kafatas\u0131n\u0131n i\u00e7 y\u00fczey \u015fekil farkl\u0131l\u0131klar\u0131n\u0131n \u00e7o\u011fu do\u011fumdan sonra geli\u015fir.\u201d diyor. \u0130ki t\u00fcr\u00fcn bebekleri do\u011fduklar\u0131nda kafatas\u0131 uzam\u0131\u015ft\u0131r ama sadece modern insan kafatas\u0131n\u0131n i\u00e7i ya\u015fam\u0131n\u0131n ilk y\u0131l\u0131nda, daha k\u00fcresel bir \u015fekle d\u00f6n\u00fc\u015f\u00fcr. Dolay\u0131s\u0131yla iki t\u00fcr\u00fcn bireyleri, yeti\u015fkin beyin b\u00fcy\u00fckl\u00fc\u011f\u00fcne farkl\u0131 yollardan geli\u015ferek eri\u015fir.<\/p>\n

Ayn\u0131 MPI ara\u015ft\u0131rmac\u0131lar\u0131 daha \u00f6nce yapt\u0131klar\u0131 ilintili bir ara\u015ft\u0131rmada, insan ve \u015fempanzelerin beyin geli\u015fimi \u00f6r\u00fcnt\u00fcs\u00fcn\u00fcn do\u011fumdan hemen sonra belirgin bi\u00e7imde farkl\u0131, ancak bir ya\u015f\u0131ndan itibaren hayli benzer oldu\u011funu g\u00f6stermi\u015flerdi. Simon Neubauer, \u201cBiz modern insan, Neanderthal ve \u015fempanzenin payla\u015ft\u0131klar\u0131 bu geli\u015fme y\u00f6nlerinin korundu\u011funu d\u00fc\u015f\u00fcn\u00fcyoruz.\u201d diyor ve ekliyor: \u201cB\u00fcy\u00fck olas\u0131l\u0131kla bu geli\u015fimsel \u00f6r\u00fcnt\u00fc \u015fempanze ve insan\u0131n birka\u00e7 milyon y\u0131l \u00f6nceki ortak atas\u0131ndan beri de\u011fi\u015fmedi.\u201d Ya\u015fam\u0131n\u0131n ilk birinci y\u0131l\u0131nda modern insan (Neanderthal de\u011fil), beyin geli\u015fiminin bu atasal \u00f6r\u00fcnt\u00fcs\u00fcnden farkl\u0131 yola sapar.<\/p>\n

Geli\u015fme boyunca iki t\u00fcr\u00fcn yeti\u015fkinleri aras\u0131nda ortaya \u00e7\u0131kan farkl\u0131l\u0131klar, beyin geli\u015fimi \u00f6r\u00fcnt\u00fcs\u00fcndeki farkl\u0131l\u0131klar\u0131n alt\u0131nda yatan neden potansiyel bili\u015fsel farkl\u0131l\u0131klar olsun olmas\u0131n, bizim anlamam\u0131z i\u00e7in \u00f6nemliydi. B\u00fcy\u00fck olas\u0131l\u0131kla do\u011fumdan sonraki periyot iki t\u00fcr aras\u0131 en \u00f6nde gelen farklar, beyin geli\u015fiminin sinaptik ve n\u00f6ral d\u00fczeni i\u00e7in etkide bulunuyorlar.<\/p>\n

Bireyin b\u00fcy\u00fcme s\u00fcrecinde bili\u015fsel yeteneklerinin geli\u015fimi, beynin a\u011f \u00f6r\u00fcnt\u00fcs\u00fcndeki olgunla\u015fmaya ba\u011fl\u0131d\u0131r. Do\u011fum \u00f6ncesi ve hemen sonras\u0131nda n\u00f6ral geli\u015fim seyrektir ve hatta klinik \u00e7al\u0131\u015fmalar, beynin geli\u015fimindeki ince de\u011fi\u015fiklileri, davran\u0131\u015flar\u0131 ve bili\u015fsel s\u00fcre\u00e7leri etkileyen n\u00f6ral a\u011f \u00f6r\u00fcnt\u00fcs\u00fcndeki de\u011fi\u015fimlere ba\u011flamakta. Modern insan\u0131n b\u00fcy\u00fcme s\u00fcrecinde \u00e7e\u015fitli beyin b\u00f6lgeleri aras\u0131nda olu\u015fan ba\u011flant\u0131lar, daha y\u00fcksek sosyal, duygusal ve ileti\u015fim fonksiyonlar\u0131 i\u00e7in \u00f6nemlidir. Bundan dolay\u0131 Neanderthallerin, d\u00fcnyay\u0131 bizim g\u00f6rd\u00fc\u011f\u00fcm\u00fcz gibi g\u00f6rmeleri olas\u0131 de\u011fildir.<\/p>\n

Bu yeni \u00e7al\u0131\u015fma g\u00f6sterdi ki modern insan do\u011fumdan sonraki beyin geli\u015fimi \u00f6r\u00fcnt\u00fcs\u00fc a\u00e7\u0131s\u0131ndan e\u015fsiz. Ve bu bizi Neanderthal gibi yak\u0131n akrabalar\u0131m\u0131zdan ay\u0131r\u0131yor. Neanderthal genom projesindeki yeni ke\u015fifler \u0131\u015f\u0131\u011f\u0131nda bu e\u015fsiz modern insan beyninin erken geli\u015fim \u00f6r\u00fcnt\u00fcs\u00fc ilgin\u00e7le\u015fiyor. \u0130ki t\u00fcr genomlar\u0131 aras\u0131ndaki kar\u015f\u0131la\u015ft\u0131rma birka\u00e7 b\u00f6lgede, Homo sapiens<\/em> y\u00f6n\u00fcnde pozitif se\u00e7ilim i\u00e7in g\u00fc\u00e7l\u00fc kan\u0131tlar ortaya \u00e7\u0131kard\u0131.<\/p>\n

Gunz, bulduklar\u0131n\u0131n iki \u00f6nemli etkiye sahip oldu\u011funu s\u00f6yl\u00fcyor: \u201cBir, iki t\u00fcr aras\u0131nda bili\u015fsel farkl\u0131l\u0131klara katk\u0131da bulunan beyin geli\u015fimi \u00f6r\u00fcnt\u00fcs\u00fcndeki farkl\u0131l\u0131klar\u0131 ke\u015ffettik. Belki daha \u00f6nemlisi, bu ke\u015fif bize Neanderthalden \u00e7ok, kendi t\u00fcr\u00fcm\u00fcz hakk\u0131nda daha fazla \u015fey s\u00f6yleyecek. Umar\u0131z ki bulduklar\u0131m\u0131z, modern insan\u0131n se\u00e7ilimine dair g\u00f6sterilen baz\u0131 genlerin i\u015flevini tan\u0131mlamaya yard\u0131mc\u0131 olsun.\u201d<\/p>\n

 <\/p>\n

Kaynak: http:\/\/www.sciencedaily.com\/releases\/2010\/11\/101108140421.htm<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

Modern insan ile Neanderthal aras\u0131nda bili\u015fsel fark olup olmamas\u0131, antropolojide ve arkeolojide tart\u0131\u015fmal\u0131 bir konudur. \u00c7\u00fcnk\u00fc bir\u00e7ok ara\u015ft\u0131rmac\u0131, modern insan ve Neanderthal beyin \u00f6l\u00e7\u00fcs\u00fc kar\u015f\u0131la\u015ft\u0131r\u0131ld\u0131\u011f\u0131nda, \u00f6nceleri bu iki t\u00fcr\u00fcn bili\u015fsel yeteneklerinin benzer oldu\u011funu d\u00fc\u015f\u00fcnd\u00fcler. Ancak beynin i\u00e7 d\u00fczenlenmesi bili\u015fsel yetenekler i\u00e7in kendi net hacminden daha \u00f6nemlidir. Beynin i\u00e7 d\u00fczeni, beyin geli\u015fiminin bi\u00e7im ve temposuna ba\u011fl\u0131d\u0131r. […]<\/p>\n","protected":false},"author":414,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[123,19],"tags":[243,529,353],"class_list":["post-10461","post","type-post","status-publish","format-standard","hentry","category-86-sayi","category-bilim-gundemi","tag-antropoloji","tag-neandertal","tag-paleoantropoloji"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t