北極 に 適応 し た 犬 は プレイストセーン から ホロセーン の 移行 期 に 出現 し た
Mikkel-Holger S Sinding1,2,3,4,5, Shyam Gopalakrishnan6, Jazmín Ramos-Madrigal6
1The GLOBE Institute, University of Copenhagen, Copenhagen, Denmark. mhssinding@gmail.com tomas.marques@upf.edu ajhansen@sund.ku.dk tgilbert@sund.ku.dk.
まとめ
ゲノム解析によると 現代のスレード犬は シベリアに起源があり 9,500年前のシベリアの犬と 古代のシベリアのオオカミの遺伝子の流れに 遺伝的つながりがあり その頃には 北極に適応していたことを示しています
科学分野:
- 犬のゲノミクス
- 進化生物学
- 考古遺伝学
背景:
- スレード・ドッグは高度に特化した犬種で,その起源に関する研究は限られている.
- 雪犬の進化を理解することは 北極の適応と人間と犬の共同進化を理解するために 極めて重要です
研究 の 目的:
- ゲノムアプローチを用いてスレード犬の空間時間的出現と進化史を調査する.
- 現代のスレード犬の集団に寄与する祖先の起源と遺伝子フローパターンを特定する.
主な方法:
- グリーンランドのスレード犬の ゲノム解析
- 9500年前のシベリアの犬の配列が 考古学的にスレード技術と結びついています
- ~33,000年前のシベリアのオオカミのゲノムの配列を比較しました.
主要な成果:
- 古代シベリア犬と現代のスレード犬の 遺伝的類似性が見つかっています
- プレイストセンのシベリアのオオカミから 現代のアメリカのオオカミではなく 現代のスレード犬に 遺伝子が流入した証拠があります
- 9500年前に存在した北極の適応と潜在的に関連しているスレード犬特有の遺伝子ハプロタイプの識別.
結論:
- 現代のスレード犬の祖先は シベリアに遡ります
- 少なくとも9500年前には シベリアで北極の環境に特異な遺伝的適応が確立した.
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