Behavior and environmental responses of deep-sea animal larvae

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K06754
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 44050:Animal physiological chemistry, physiology and behavioral biology-related
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: Miyamoto Norio 国立研究開発法人海洋研究開発機構, 超先鋭研究開発部門(超先鋭研究開発プログラム), 研究員 (20612237)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: プランクトン幼生 / 分散 / 行動 / 神経系 / 発生

Outline of Final Research Achievements

Many organisms live only in limited environments on the deep sea floor, such as hydrothermal vents and whalefall area. It is not well understood how these organisms disperse and arrive at new habitats. In this study, we aimed to elucidate the dispersal mechanism of organisms on the deep-sea floor, using the bone-eating worm Osedax japonicus, which is unique to the deep-sea whalefall ecosystem, as a model. We described the development of the larval ciliary bands and nervous system in detail. We also examined the survival period and temperature tolerance of the larvae. The results suggested that the larvae of O. japonicus do not float in the surface throughout their development but disperse by bottom currents near the sea floor. The involvement of serotonergic neurons in larval swimming behavior was also revealed.

Free Research Field

海洋生物学

Academic Significance and Societal Importance of the Research Achievements

生物の分散は、生息場所の拡大や他の個体群との遺伝的な交流をもたらす生態学的・進化生物学的に重要な過程である。深海生物は採集や飼育が困難であることから、具体的な分散過程が解明されている種は存在していない。ホネクイハナムシは唯一安定して継代飼育が可能な深海生物であり、幼生の飼育を通して行動や分散過程を解明した本研究は、深海の生態学的研究に新たな知見をもたらすものである。また深海生物の分散メカニズムを理解することは、海洋生物の保全をどのように行うべきなのかの判断材料となる。