Rare, long‐distance dispersal events are a key process in generating and maintaining patterns in biological diversity and species distributions across space and time. The 9.0 magnitude earthquake that struck the eastern coast of Japan in 2011, and the subsequent 38 m high tsunami washed large amounts of shoreline debris into the Pacific Ocean that led to a large‐scale biological rafting event carrying nearly 300 marine species to the western shores of North America. Whether oceanic, trans‐Pacific dispersal via rafting generates long distance dispersal events for small, flightless, terrestrial species is unknown. By sampling beach debris associated with known hot‐spots of tsunami debris along the north and east shores of Graham Island, Haida Gwaii, Canada, I document significantly dissimilar invertebrate communities associated with tide‐line beach debris and the occurrence of several putative Japanese species of soil‐dwelling mites (Acari: Oribatida). Previous explanations of Haida Gwaii's unique flora and fauna have been attributed to a proximity to the Beringian land bridge and the accumulated evidence of near‐offshore glacial refugia during the last glacial period. However, my research also suggests that stochastic, trans‐Pacific rafting events contribute to the biodiversity and biogeography of soil communities on the west coast of North America.

中文翻译：

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通过碎片漂流对海洋物种进行越洋扩散

罕见的远距离传播事件是生成和维持生物多样性和物种在空间和时间上分布的模式的关键过程。2011年袭击日本东海岸的9.0级地震和随后的38 m高海啸将大量海岸线碎片冲入了太平洋，导致大规模的生物漂流事件，将近300种海洋生物带到了西海岸北美。通过漂流进行海洋性跨太平洋扩散是否会为小的，无法飞行的陆地物种产生长距离扩散事件，这一点尚不清楚。通过对加拿大海达瓜岛Graham岛北岸和东岸与已知海啸碎片热点相关的海滩碎片进行采样，我记录了与潮汐线海滩残骸和几种假定的日本栖居螨类相关的无脊椎动物群落（Acari：Oribatida）。先前对海达瓜的独特动植物的解释是由于靠近白令陆桥和在最后一个冰川时期积累了近海冰川避难所的证据。但是，我的研究还表明，随机的，跨太平洋漂流事件有助于北美洲西海岸土壤群落的生物多样性和生物地理。其独特的动植物区系归因于靠近白令陆桥和在最后一次冰川期积累的近海冰川避难所的证据。但是，我的研究还表明，随机的，跨太平洋漂流事件有助于北美洲西海岸土壤群落的生物多样性和生物地理。其独特的动植物区系归因于靠近白令陆桥和在最后一次冰川期积累的近海冰川避难所的证据。但是，我的研究还表明，随机的，跨太平洋漂流事件有助于北美洲西海岸土壤群落的生物多样性和生物地理。