کد مقاله کد نشریه سال انتشار مقاله انگلیسی ترجمه فارسی نسخه تمام متن
2783396 1153741 2015 8 صفحه PDF سفارش دهید دانلود رایگان
عنوان انگلیسی مقاله ISI
The role of Pleistocene glaciations in shaping the evolution of polar and brown bears. Evidence from a critical review of mitochondrial and nuclear genome analyses
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
سفارش ترجمه تخصصی
با تضمین قیمت و کیفیت
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم کشاورزی و بیولوژیک (عمومی)
پیش نمایش صفحه اول مقاله
The role of Pleistocene glaciations in shaping the evolution of polar and brown bears. Evidence from a critical review of mitochondrial and nuclear genome analyses
چکیده انگلیسی

In this report, I review recent molecular studies dealing with the origin and evolution of polar bears (Ursus maritimus), with special emphasis on their relationships with brown bears (U. arctos). On the basis of mitochondrial and nuclear data, different hypotheses have been proposed, including rapid morphological differentiation of U. maritimus, genetic introgression from U. arctos into U. maritimus, or inversely from U. maritimus into U. arctos, involving either male- or female-mediated gene flow. In the light of available molecular and eco-ethological data, I suggest, firstly, that all divergences among major clades of large bears can be linked to glacial periods, secondly, that polar bears diverged from brown bears before 530 thousand years ago (ka), during one of the three glacial marine isotope stages (MIS) 14, 15.2 or 16, and, thirdly, that genetic introgression had occurred from female polar bears into brown bear populations during at least two glacial periods, at 340 ± 10 ka (MIS 10) in western Europe, and at 155 ± 5 ka (MIS 6) on the ABC islands of southeastern Alaska, and probably also in Beringia and Ireland based on ancient DNA sequences.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Comptes Rendus Biologies - Volume 338, Issue 7, July 2015, Pages 494–501
نویسندگان
,
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
سفارش ترجمه تخصصی
با تضمین قیمت و کیفیت