Search Results - "Wani, Ryoji"

Geological duration of ammonoids controlled their geographical range of fossil distribution by Wani, Ryoji

“…The latitudinal distributions in Devonian-Cretaceous ammonoids were analyzed at the genus level, and were compared with the hatchling sizes (i.e., ammonitella…”
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Stepwise growth changes in early post-embryonic stages among Cretaceous tetragonitid ammonoids by Kawakami, Yoshitaka, Wani, Ryoji

“…In this study, we analyzed the ontogenetic trajectories of shell morphology in some Cretaceous tetragonitid ammonoid specimens (Tetragonitidae) collected from…”
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Weaving of biomineralization framework in rotaliid foraminifera: implications for paleoceanographic proxies by Nagai, Yukiko, Uematsu, Katsuyuki, Chen, Chong, Wani, Ryoji, Tyszka, Jarosław, Toyofuku, Takashi

“…Elemental and/or isotopic signatures of calcareous tests of foraminifera are commonly used to reconstruct paleoenvironmental conditions. A major problem, often…”
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Polymorphism in Late Cretaceous phylloceratid ammonoids: evidence from ontogenetic trajectories of septal spacing by Iwasaki, Tetsuro, Iwasaki, Yui, Wani, Ryoji, Brayard, Arnaud

“…The ontogenetic trajectories of septal spacing between succeeding chambers of two phylloceratid ammonoids, Hypophylloceras subramosum and Phyllopachyceras…”
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Preservation of nautilid soft parts inside and outside the conch interpreted as central nervous system, eyes, and renal concrements from the Lebanese Cenomanian by Klug, Christian, Pohle, Alexander, Roth, Rosemarie, Hoffmann, René, Wani, Ryoji, Tajika, Amane

“…Nautilid, coleoid and ammonite cephalopods preserving jaws and soft tissue remains are moderately common in the extremely fossiliferous Konservat-Lagerstätte…”
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Reading the Fine Print: Ultra-Microstructures of Foraminiferal Calcification Revealed Using Focused Ion Beam Microscopy by Nagai, Yukiko, Uematsu, Katsuyuki, Wani, Ryoji, Toyofuku, Takashi

“…The elemental composition of calcite is of critical value in paleoceanographic reconstructions, yet little is known about biological processes underlying…”
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Intraspecific variation of phragmocone chamber volumes throughout ontogeny in the modern nautilid Nautilus and the Jurassic ammonite Normannites by Tajika, Amane, Morimoto, Naoki, Wani, Ryoji, Naglik, Carole, Klug, Christian

“…Nautilus remains of great interest to palaeontologists after a long history of actualistic comparisons and speculations on aspects of the palaeoecology of…”
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Variable Growth Modes in Late Cretaceous Ammonoids: Implications for Diverse Early Life Histories by Arai, Kazato, Wani, Ryoji

“…Examination of ontogenetic changes in the septal angle of Late Cretaceous ammonoids (ten species representing seven superfamilies and four suborders) reveals…”
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Covariance of sutural complexity with whorl shape: evidence from intraspecific analyses of the Cretaceous ammonoid Desmoceras by Aiba, Daisuke, Wani, Ryoji

“…In order to test the hypothesis that complex suture lines in ammonoids reinforced their shell strength, intraspecific variation of sutural complexity and shell…”
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Ontogenetic Change and Intra-specific Variation of Shell Morphology in the Cretaceous Nautiloid (Cephalopoda, Mollusca) Eutrephoceras clementinum (D'Orbigny, 1840) from the Ariyalur Area, Southern India by Wani, Ryoji, Ayyasami, Krishnan

“…Morphometric analyses of shell morphology in the Cretaceous nautiloid Eutrephoceras clementinum (d'Orbigny, 1840) (Cephalopoda, Mollusca) from the Ariyalur…”
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The peculiar taphonomy of the streamlined late Campanian ammonite Metaplacenticeras subtilistriatum from northern Hokkaido, Japan by Wani, Ryoji

“…The peculiar taphonomy of the late Campanian ammonite Metaplacenticeras subtilistriatum is reconstructed on the basis of stratigraphic occurrence within the…”
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Large hatchling size in Cretaceous nautiloids persists across the end-Cretaceous mass extinction: New data of Hercoglossidae hatchlings by Wani, Ryoji, Kurihara, Ken’ichi, Ayyasami, Krishnan

“…The hatchling sizes of the Cretaceous nautiloids ( Hercoglossa forbesianus and Cimomia angustus; Hercoglossidae) are reported here for the first time as…”
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Abrupt changes in distance between succeeding septa at the hatching time in modern coleoids Sepiella japonica and Spirula spirula by Yamaguchi, Ayaka, Kumada, Yuichiro, Alfaro, Andrea C., Wani, Ryoji

“…Analyses of distances between succeeding septa throughout ontogeny of modern coleoids Sepiella japonica and Spirula spirula reveal that the first several septa…”
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Old and sticky—adhesive mechanisms in the living fossil Nautilus pompilius (Mollusca, Cephalopoda) by von Byern, Janek, Wani, Ryoji, Schwaha, Thomas, Grunwald, Ingo, Cyran, Norbert

“…Nautiloidea is the oldest group within the cephalopoda, and modern Nautilus differs much in its outer morphology from all other recent species; its external…”
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Preferential predatory peeling: Ammonoid vs. nautiloid shells from the Upper Carboniferous of Texas, USA by Wani, Ryoji, Jenkins, Robert G., Mapes, Royal H.

“…Narrow groove-like excavations on ammonoid and coiled nautiloid shells are rare in Upper Carboniferous units from Texas, USA. The morphological characteristics…”
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Ontogenetic trajectories of septal spacing and conch shape in the Late Cretaceous gaudryceratid ammonoids: implications for their post‐embryonic palaeoecology by Kawakami, Yoshitaka, Uchiyama, Naomi, Wani, Ryoji, Korn, Dieter

“…In this study, we analysed the ontogenetic trajectories of septal spacing between succeeding chambers of the gaudryceratid ammonoid, Gaudryceras tenuiliratum,…”
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Limited Migration of Scaphitid Ammonoids: Evidence from the Analyses of Shell Whorls by Yahada, Hiroyuki, Wani, Ryoji

“…The thickness ratios of shells (=whorl breadth/shell diameter) in the heteromorphic scaphitid ammonoid Scaphites planus (Yabe, 1910) from the lower middle…”
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Different Modes of Migration Among Late Cretaceous Ammonoids in Northwestern Hokkaido, Japan: Evidence from the Analyses of Shell Whorls by Ikeda, Yasufumi, Wani, Ryoji

“…The thickness ratios of shell whorls ( = whorl breadth/shell diameter) in the ammonoids Damesites sugata (Forbes, 1845), Hypophylloceras subramosum (Shimizu,…”
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Ontogenetic trajectories of septal spacing in Early Jurassic belemnites from Germany and France, and their palaeobiological implications by Wani, Ryoji, Tajika, Amane, Ikuno, Kenji, Iwasaki, Tetsuro, Korn, Dieter

“…Based on well‐preserved belemnites, the ontogenetic trajectories of septal spacing between succeeding chambers were analysed. In the examined species…”
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Permanent El Niño during the Pliocene warm period not supported by coral evidence by Watanabe, Tsuyoshi, Suzuki, Atsushi, Minobe, Shoshiro, Kawashima, Tatsunori, Kameo, Koji, Minoshima, Kayo, Aguilar, Yolanda M, Wani, Ryoji, Kawahata, Hodaka, Sowa, Kohki, Nagai, Takaya, Kase, Tomoki

“…The El Niño/Southern Oscillation (ENSO) system during the Pliocene warm period (PWP; 3-5 million years ago) may have existed in a permanent El Niño state with…”
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