法國(guó)原子能委員會(huì)和法國(guó)國(guó)家科研中心研究人員最近通過(guò)分析洞熊的細(xì)胞基因組后發(fā)現(xiàn),，這種動(dòng)物160萬(wàn)年前與現(xiàn)存的棕熊擁有共同祖先,。
這兩家機(jī)構(gòu)在一份公報(bào)中介紹說(shuō),，距今30萬(wàn)年到1.5萬(wàn)年前,，洞熊生活在歐洲和中東地區(qū),，隨后由于氣候變化和人類狩獵等原因而滅絕,。為了對(duì)這種龐大的動(dòng)物有更深入的了解,，科學(xué)家們對(duì)在法國(guó)南部阿爾代什省巖洞中發(fā)現(xiàn)的一塊洞熊骨進(jìn)行了DNA檢測(cè),，并獲得了完整的基因組數(shù)據(jù)?；蚪M內(nèi)的線粒體能夠?yàn)槿藗兲峁┰敿?xì)的動(dòng)物機(jī)體演化信息,，通過(guò)它可以判斷出洞熊與棕熊何時(shí)發(fā)生了分化。
科學(xué)家們分析后推斷,，洞熊與棕熊在160萬(wàn)年前發(fā)生分化,，此前，它們與北極熊都擁有同一個(gè)祖先,。
這一研究成果已發(fā)表在最新一期美國(guó)《國(guó)家科學(xué)院院刊》上,。（生物谷Bioon.com）
生物谷推薦原始出處：
Proceedings of the National Academy of Sciences，doi: 10.1073/pnas.0806143105,，Céline Bon,，Jean-Marc Elalouf
Deciphering the complete mitochondrial genome and phylogeny of the extinct cave bear in the Paleolithic painted cave of Chauvet
Céline Bona, Nicolas Caudya, Maud de Dieuleveulta, Philippe Fosseb, Michel Philippec, Frédéric Maksudd, éliane Beraud-Colombe, Eric Bouzaide, Rym Kefie, Christelle Laugierf, Bernard Rousseauf, Didier Casaneg, Johannes van der Plichth, and Jean-Marc Elaloufa,i,1
aService de Biologie Intégrative et Génétique Moléculaire,
fService de Chimie Bioorganique et de Marquage, Institut de Biologie et Technologies de Saclay, Commissariat à l'énergie Atomique Saclay, 91191 Gif-sur-Yvette Cedex, France;
bCentre National de la Recherche Scientifique Unité Mixte de Recherche 5608, Université Toulouse le Mirail, 31058 Toulouse Cedex 1, France;
cMuséum d'Histoire Naturelle, 28 Boulevard des Belges, 69000 Lyon, France;
dService Régional de l'Archéologie, 32 Rue de la Dalbade, BP811 31080 Toulouse cedex 6, France;
eInstitut National de la Santé et de la Recherche Médicale U600, H?pital Sainte Marguerite, 270 Boulevard Sainte Marguerite, 13009 Marseille, France;
gLaboratoie Evolution, Génomes et Spéciation, Unité Propre de Recherche 9034 Centre National de la Recherche Scientifique, 91198 Gif-sur-Yvette Cedex, France;
hRadiocarbon Laboratory, Groningen University, Nijenborgh 4, 9747 AG Groningen, The Netherlands; and
iFaculty of Archaeology, Leiden University, P.O. Box 9515, 2300 RA Leiden, The Netherlands
Abstract
Retrieving a large amount of genetic information from extinct species was demonstrated feasible, but complete mitochondrial genome sequences have only been deciphered for the moa, a bird that became extinct a few hundred years ago, and for Pleistocene species, such as the woolly mammoth and the mastodon, both of which could be studied from animals embedded in permafrost. To enlarge the diversity of mitochondrial genomes available for Pleistocene species, we turned to the cave bear (Ursus spelaeus), whose only remains consist of skeletal elements. We collected bone samples from the Paleolithic painted cave of Chauvet-Pont d'Arc (France), which displays the earliest known human drawings, and contains thousands of bear remains. We selected a cave bear sternebra, radiocarbon dated to 32,000 years before present, from which we generated overlapping DNA fragments assembling into a 16,810-base pair mitochondrial genome. Together with the first mitochondrial genome for the brown bear western lineage, this study provides a statistically secured molecular phylogeny assessing the cave bear as a sister taxon to the brown bear and polar bear clade, with a divergence inferred to 1.6 million years ago. With the first mitochondrial genome for a Pleistocene carnivore to be delivered, our study establishes the Chauvet-Pont d'Arc Cave as a new reservoir for Paleogenetic studies. These molecular data enable establishing the chronology of bear speciation, and provide a helpful resource to rescue for genetic analysis archeological samples initially diagnosed as devoid of amplifiable DNA.
