新世界犬の旧世界起源に関する古代DNAの証拠
Jennifer A Leonard1, Robert K Wayne, Jane Wheeler
1Department of Organismic Biology, Ecology and Evolution, University of California, Los Angeles, CA 90095-1606, USA. Leonard.Jennifer@NMNH.SI.edu
Science (New York, N.Y.)
|November 26, 2002
まとめ
アメリカ大陸の古代犬のDNAは,複数の旧世界の系統からの起源を明らかにしています. 現代の犬には存在しないユニークな新世界犬の系統は,ヨーロッパ人入植者が先住民族の犬集団を混乱させたことを示唆しています.
科学分野:
- パレオゲノミクスとは
- 犬の進化についてです.
- 考古遺伝学 考古遺伝学
背景:
- 飼い犬 (Canis lupus familiaris) の起源と多様化は,人間の移住に関連しています.
- アメリカ大陸の犬の遺伝的歴史を理解することは,コロンブス以前の人間と犬の相互作用の洞察を提供します.
研究 の 目的:
- ミトコンドリアDNAを用いて,アメリカ大陸の古代犬の起源と遺伝的多様性を調査する.
- 古代アメリカ犬と旧世界犬の集団の関係を見極めるため.
- アメリカ先住民の犬の系統にヨーロッパ人による植民地化の影響を調査する.
主な方法:
- 古代の犬のミトコンドリアDNA (mtDNA) 配列解析は,ラテンアメリカとアラスカから発見された遺物です.
- 古代のシーケンスと旧世界と現代の犬の系統を比較するための系統分析.
- 独特のクラードを特定し,遺伝的多様性を評価するために,集団遺伝分析を行います.
主要な成果:
- 古代アメリカの犬は,ベーリング海峡を渡って人間と共に移住した複数の旧世界犬の系統から生まれた.
- 新世界に特有の異なったミトコンドリアDNAクラードが特定され,地理的隔離の期間を示しています.
- このユニークな新世界クラードは,現代の犬の大きなサンプルに顕著に欠けていました.
結論:
- ネイティブ・アメリカン・ドッグの祖先は,旧世界からの複数の独立した導入にたどり着く.
- 新世界犬の遺伝的特異性は,最初に到着した後に隔離された期間を強調しています.
- 独特のネイティブ・ドッグ・クラードの消失は,ヨーロッパ人入植者による体系的な抑圧を示唆し,先住民族の犬群に影響を及ぼした.
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