Dear colleagues, We are pleased to announce a new publication on how marine mammals may have driven the regional extinctions of nautiloid cephalopods globally in the Cenozoic and led to the current distribution. Kiel S, Goedert JL, and Tsai CH. 2022. Seals, whales, and the Cenozoic decline of nautiloid cephalopods. Journal of Biogeography, doi: 10.1111/jbi.14488 Abstract Aim *Nautilus* and *Allonautilus*, last members of the once widespread nautiloid cephalopods, are today restricted to the deep central Indo-West Pacific Ocean, for reasons that remain unclear. Cephalopod evolution is generally considered as being driven by vertebrate predation; therefore, we investigated the role of whales and seals in the decline of nautiloids through the Cenozoic. Location Global. Taxon Nautiloids, pinnipeds, cetaceans. Methods Distribution data for nautiloids, pinnipeds and cetaceans through the Cenozoic were compiled and plotted on a series of paleogeographic maps. Nautiloid shell sizes were compiled and plotted against the first appearance of pinnipeds and cetaceans in key regions. Results
From the Oligocene onward, nautiloids became extinct in areas where pinnipeds appeared. The exception is the agile nautiloid *Aturia*, extinct globally at the end of the Miocene. A major role of odontocetes in the demise of nautiloids is not apparent, except for a few brevirostrine Oligocene taxa from the North American Atlantic and Pacific coasts, which appeared in these areas at the same time as nautilids disappeared. The Oligocene disappearance of nautiloids (except *Aturia*) from the American Pacific coasts coincides with the development of oxygen minimum zones (OMZs) in this region.
Main conclusions We hypothesize that the Cenozoic spread of pinnipeds drove nautiloids into their present-day central Indo-West Pacific refuge. Additional factors for the local extinction of nautiloids in the Oligocene include predation by short-snouted whales and the development of OMZs, preventing nautiloids from retreating into deeper water. Significance statement The iconic “living fossil” Nautilus occurs mainly in the deep tropical Indo-West Pacific Ocean. The fossil record indicates that this restriction from a once worldwide distribution was largely driven by the Cenozoic spread of seals, highlighting the role of vertebrate predation in the evolution of cephalopods. This paper is freely available here: https://onlinelibrary.wiley.com/doi/10.1111/jbi.14488 Regards and all the best, Tsai -- 蔡政修（Cheng-Hsiu Tsai さい まさのぶ) PhD Lab of evolution and diversity of fossil vertebrates（古脊椎動物演化及多樣性實驗室） Department of Life Science & Institute of Ecology and Evolutionary Biology（生命科學系＆生態學與演化生物學研究所） National Taiwan University（台灣大學） No. 1, Sec. 4, Roosevelt Rd., Taipei, 106-17, Taiwan（台灣 106-17 台北市羅斯福路 4 段 1 號） Email: whaletsai@ntu.edu.tw; craniata@gmail.com https://www.facebook.com/NTUWhaleTsai/?modal=admin_todo_tour Tel: 886 - 2 - 3366 - 2448