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琥珀内昆虫化石の神経解剖学的研究
No full textInsects contain 1 million species, accounting for more than 50% of all species. These most diverse organisms on Earth originated over 400 million years ago, and they have pioneered and adapted to the new environments until the present. The unique sensory system of insects is one of the key adaptations that have supported their ongoing evolutionary success. Insect sensory organs are miniaturized, while they have chitinous exoskeletons and high fossilization potential, especially in amber, the best preservational medium. Previous studies, unfortunately, have missed these notable minute sensors due to a lack of viewpoints and low-resolution methodology. Here, I revealed the exceptionally well-preserved sensory organs of insects in Cretaceous amber while developing novel visualization methods. Their unique morphology enabled the direct comparison with extant counterparts and functional reconstruction in ecological contexts. This study focused on the three insect taxa used as traditional models of modern neurobiology: cockroaches, ants, and mantises. The eyes and antennae of the 100-million-year-old cockroach suggested that the species had a different ecology from extant relatives in active time and sexual communication. The earliest ants showed antennal sensory properties shared with those of extant species, indicating possession of advanced pheromone communication and sociality. The well-developed vision with high visual resolution and stereoscopic prey recognition was revealed in the Cretaceous mantis species, which is the closest out-group of all modern mantodeans. The advanced visual system of mantises has likely supported their principal predatory niches for 90 million years. The miniaturized and sophisticated peripheral nervous systems of these insects tell us about their ancient behavioral ecology, including social and predatory adaptations, and their evolutionary timelines based on direct sensory evidenc
イネの四次元イメージングを用いた器官および細胞レベルにおける複雑な形態学的動態の分析 [全文の要約]
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とかち鹿追ジオパークからの知見にもとづく中国のジオパークに対するジオ教育の枠組みの提案 [全文の要約]
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日本語と中国語における分配量化と全称量化の生成文法による分析 [全文の要約]
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