ラゴモルフ哺乳類の脊椎の形態学的変化の多層分析

Nuttakorn Taewcharoen¹, Megu Gunji², Rachel Norris³

¹School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia.

Journal of evolutionary biology

|August 28, 2025

まとめ

哺乳類の脊柱の変異は種と系統学的レベルによって異なる. 種内のパターンを理解することは,哺乳類のより広範な形態学的多様性を説明する鍵です.

科学分野:

* 進化生物学
* 比較解剖学
* 形態学的変化

背景:

* 脊柱の形状は,種内の多様性を無視して,広範な系統学的スケールで研究される.
* 種内の形態的多様性と種間の形態的多様性の関係を理解する点でギャップが存在します.
* 種内分析には通常より大きなサンプルサイズが必要で,これは一般的な制限です.

研究の目的:

* 脊椎内の形態学的変化を種内レベルで調査する.
* 種内の変動と,異なる系統遺伝的レベル (ウサギ/ウサギ,レポリidae,ラゴモルファ,陸上の胎盤) 間の変動を比較する.
* 種間の変動が,種内の変動の拡大版であるかどうかを判断する.

主な方法:

* 脊柱の形状を分析するために,幾何学的形状測定を用いた.
* 各標本から9本の脊椎を採取し,複数の種と遺伝子レベルで採取した.
* 脊椎の形状のプロクロステス変数は,形態学的変数 (プロフィール) の指標として計算された.

主要な成果:

* 脊椎に沿った形態学的変異のプロファイルは,種によって著しく異なります.
* 変異パターンは,種内および種間遺伝的レベルによっても異なります.
* 種間の変動は,単に種内の変動の拡大されたバージョンを表しているわけではありません.

結論:

* 哺乳類の脊柱の進化を理解するには,多層の分析方法が不可欠です.
* 種内の形態学的変化パターンは,種間の多様性を説明するために直接拡大しません.
* この研究は,哺乳類の脊椎の進化動態に関する洞察を提供します.

キーワード:

格差異種間の変化種内での変化構造的進化

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