ハセガワ　ナオヒロ   HASEGAWA Naohiro   長谷川　尚弘    所属   広島修道大学  人間環境学部    職種   助教
言語種別	英語
発行・発表の年月	2024/01
形態種別	学術論文
標題	From solitary to colonial with zooid miniaturization: ancestral-state reconstruction based on NGS data of stolidobranch ascidians
執筆形態	共著
掲載誌名	bioRxiv
掲載区分	国外
出版社・発行元	bioRxiv
巻・号・頁	pp.1-54
頁数	54
担当範囲	筆頭著者・責任著者として、研究の全工程に携わった。具体的には、研究計画、研究費の獲得、材料の採集・同定、RNAの抽出、NGSデータの解析、Pythonスクリプトの作成、分子系統解析、祖先形質復元、原稿の執筆を行った。
著者・共著者	◎Naohiro Hasegawa, Shin Matsubara, Akira Shiraishi, Honoo Satake, Hiroshi Kajihara
概要	The evolutionary process of zooid miniaturization in colonial animals has remained enigmatic. The ascidian family Styelidae (Stolidobranchia) exhibits diverse coloniality, making it suitable for studying this phenomenon. We reconstructed phylogenomic relationships of 42 ascidians using transcriptomes from 17 species sampled in Israel and Japan and 25 from published data. Ancestral-state analysis revealed a directional trend: after the acquisition of coloniality, zooids became progressively smaller. This miniaturization likely reflects adaptation to limited marine substrate, promoting rapid asexual cycles and colony expansion. A mathematical model supported this view, indicating that reduced zooid size enhances reproductive speed under spatial constraints. Our results also showed that coloniality evolved independently three times within Styelidae. 担当部分：筆頭・責任著者として全頁を執筆した。