The study of the rostral neurovascular system using CT scanning has shed new light on phylogenetic and palaeobiological reconstructions of many extinct tetrapods. This research shows a detailed description of the rostral neurovascular canals of Tyrannosaurus rex including the nasal, maxillary (dorsal alveolar), and mandibular (ventral alveolar) canals. Extensive comparisons with published descriptions show that the pattern of these canals in Tyrannosaurus is not unusual for a non-avian theropod. As in the non-avian theropod Neovenator, the maxillary canal shows several anastomoses of its branches. Differences from the plesiomorphic sauropsid condition are concentrated within the canal for the maxillary neurovasculature, which is primitively horizontal, tubular, and connected to a single row of supralabial foramina, whereas in Tyrannosaurus the main trunk of the canal is oriented more obliquely and dorsally displaced to give room to the deep tooth alveolae. As a result, the lateral branches that provide innervation and blood supply to the skin are dorsoventrally elongated compared to non-theropod taxa, and multiple rows of supralabial foramina are present. An overview of the literature suggests that the evolution of the trigeminal canals among sauropsids only weakly supports previous hypotheses of crocodile-like facial sensitivity in non-avian theropods (except, maybe, in semiaquatic taxa). More systematic studies of the rostral neurovascular canals in non-avian theropods may help answer the question of whether lips were present or not. Florian Bouabdellah. Universities of Poitiers, 15 Rue de l'Hôtel Dieu, TSA 71117, 86000 Poitiers, France. florian.bouabdellah@hotmail.com Emily Lessner. University of Missouri School of Medicine, Columbia, MO, 65211, USA. ejlessner@mail.missouri.edu Julien Benoit. Evolutionary Studies Institute and School of Geosciences, University of the Witwatersrand, Johannesburg 2050, South Africa, julien.benoit@wits.ac.za
利用CT扫描对吻侧神经血管系统的研究为许多已灭绝的四足动物的系统发育和古生物学重建提供了新的思路。本研究详细描述了霸王龙的鼻侧神经血管管，包括鼻、上颌(牙槽背侧)和下颌(牙槽腹侧)的神经血管管。与已发表的描述进行的广泛比较表明，暴龙身上这些沟渠的模式对于非鸟类兽脚亚目动物来说并不罕见。与非鸟类兽脚亚目Neovenator一样，上颌管显示出其分支的几个吻合处。与多形龙的不同之处在于上颌神经血管的管道内，它是原始的水平管状，与单排颚上孔相连，而暴龙的管道主干定向更斜，并向背侧移位，以便为深牙槽提供空间。因此，与非兽脚亚目动物相比，为皮肤提供神经支配和血液供应的侧支是背侧延长的，并且存在多行颚上孔。文献综述表明，蜥脚类动物三叉神经管的进化只能微弱地支持先前的假设，即非鸟类兽脚亚目动物具有类似鳄鱼的面部敏感性(可能半水生分类群除外)。对非鸟类兽脚亚目动物的吻侧神经血管管进行更系统的研究可能有助于回答嘴唇是否存在的问题。Florian Bouabdellah。普瓦捷大学，15 Rue de l'Hôtel Dieu, TSA 71117，法国普瓦捷86000。florian.bouabdellah@hotmail.com Emily Lessner。美国密苏里大学医学院，哥伦比亚，密苏里州，65211ejlessner@mail.missouri.edu朱利安·伯努瓦。威特沃特斯兰德大学进化研究所和地球科学学院，约翰内斯堡2050，南非，julien.benoit@wits.ac.za
{"title":"The rostral neurovascular system of Tyrannosaurus rex","authors":"Florian Bouabdellah, Emily J Lessner, J. Benoit","doi":"10.26879/1178","DOIUrl":"https://doi.org/10.26879/1178","url":null,"abstract":"The study of the rostral neurovascular system using CT scanning has shed new light on phylogenetic and palaeobiological reconstructions of many extinct tetrapods. This research shows a detailed description of the rostral neurovascular canals of Tyrannosaurus rex including the nasal, maxillary (dorsal alveolar), and mandibular (ventral alveolar) canals. Extensive comparisons with published descriptions show that the pattern of these canals in Tyrannosaurus is not unusual for a non-avian theropod. As in the non-avian theropod Neovenator, the maxillary canal shows several anastomoses of its branches. Differences from the plesiomorphic sauropsid condition are concentrated within the canal for the maxillary neurovasculature, which is primitively horizontal, tubular, and connected to a single row of supralabial foramina, whereas in Tyrannosaurus the main trunk of the canal is oriented more obliquely and dorsally displaced to give room to the deep tooth alveolae. As a result, the lateral branches that provide innervation and blood supply to the skin are dorsoventrally elongated compared to non-theropod taxa, and multiple rows of supralabial foramina are present. An overview of the literature suggests that the evolution of the trigeminal canals among sauropsids only weakly supports previous hypotheses of crocodile-like facial sensitivity in non-avian theropods (except, maybe, in semiaquatic taxa). More systematic studies of the rostral neurovascular canals in non-avian theropods may help answer the question of whether lips were present or not. Florian Bouabdellah. Universities of Poitiers, 15 Rue de l'Hôtel Dieu, TSA 71117, 86000 Poitiers, France. florian.bouabdellah@hotmail.com Emily Lessner. University of Missouri School of Medicine, Columbia, MO, 65211, USA. ejlessner@mail.missouri.edu Julien Benoit. Evolutionary Studies Institute and School of Geosciences, University of the Witwatersrand, Johannesburg 2050, South Africa, julien.benoit@wits.ac.za","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69147996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vertebrate paleontology was born from the efforts of amateur and commercial fossil collectors in the nineteenth century. Amateur fossil collecting is a popular hobby in the USA, though owing to different ownership laws, American vertebrate paleontologists have less positive attitudes toward amateur collectors than in Europe where amateur and professional collectors work synergistically. Collections-based and literature surveys were conducted to evaluate the scientific contribution of amateurs to vertebrate paleontology near Santa Cruz, California. The first was a survey of museum collections identifying collector status (amateur or professional) of fossils from two formations (Santa Margarita Sandstone, Purisima Formation). The second was a com-prehensive literature survey for these two stratigraphic units, documenting whether fossils were collected by amateurs or professionals. The third was a literature survey of all published (2009-2021) Cenozoic marine vertebrate records for the Pacific coast of North America (Alaska to Baja California, Mexico). The first survey indicates that amateurs have contributed the most (75.9%) to Santa Margarita Formation specimens and over a third (38.1%) of Purisima Formation specimens. These contributions are of high quality as they are included in 40% of all publications through time in the study area, and amateur-collected fossils are reported in half (49%) of all publications from the Pacific coast over the past decade. These findings indicate that amateur collectors are not only capable of collecting scientifically significant specimens, but appear to be integral to the study of Cenozoic marine vertebrates on the Pacific coast. Dismissive attitudes towards amateur collectors are clearly unwarranted. Advice for cultivating strong professional-amateur relations is provided.
{"title":"Amateur collectors are critical to the study of fossil vertebrates: A case study from two Neogene localities in Northern California (Santa Margarita and Purisima formations)","authors":"R. Boessenecker","doi":"10.26879/1199","DOIUrl":"https://doi.org/10.26879/1199","url":null,"abstract":"Vertebrate paleontology was born from the efforts of amateur and commercial fossil collectors in the nineteenth century. Amateur fossil collecting is a popular hobby in the USA, though owing to different ownership laws, American vertebrate paleontologists have less positive attitudes toward amateur collectors than in Europe where amateur and professional collectors work synergistically. Collections-based and literature surveys were conducted to evaluate the scientific contribution of amateurs to vertebrate paleontology near Santa Cruz, California. The first was a survey of museum collections identifying collector status (amateur or professional) of fossils from two formations (Santa Margarita Sandstone, Purisima Formation). The second was a com-prehensive literature survey for these two stratigraphic units, documenting whether fossils were collected by amateurs or professionals. The third was a literature survey of all published (2009-2021) Cenozoic marine vertebrate records for the Pacific coast of North America (Alaska to Baja California, Mexico). The first survey indicates that amateurs have contributed the most (75.9%) to Santa Margarita Formation specimens and over a third (38.1%) of Purisima Formation specimens. These contributions are of high quality as they are included in 40% of all publications through time in the study area, and amateur-collected fossils are reported in half (49%) of all publications from the Pacific coast over the past decade. These findings indicate that amateur collectors are not only capable of collecting scientifically significant specimens, but appear to be integral to the study of Cenozoic marine vertebrates on the Pacific coast. Dismissive attitudes towards amateur collectors are clearly unwarranted. Advice for cultivating strong professional-amateur relations is provided.","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69148218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Iguanodontians are a large and biogeographically widespread group of dinosaurs, known from every modern continent, with a temporal range from the Late Jurassic through the Late Cretaceous. While the nested hadrosauroids have been studied extensively, the phylogeny of non-hadrosauroid iguanodontians remains less clear. This study presents a character matrix with 323 characters, and both parsimony and time-calibrated Bayesian analyses. While these result in different topologies, they both recover a Thescelosauridae outside of Iguanodontia. Within Iguanodontia, they both recover Muttaburrasaurus and Tenontosaurus as sister taxa to Rhabdodontidae, with a larger group of Gondwanan Rhabdodontoidea (nomen cladi novum) in the Bayesian analysis. A small Dryosauridae forms the sister group to Ankylopollexia, which has Uteodon and Camptosaurus as the most basally branching taxa. Within Styracosterna two distinct clades are recovered: Iguanodontidae, and a group of taxa with robust forelimbs. The holotype of Mantellisaurus is sister to “Dollodon”, supporting the hypothesis that these taxa are synonymous. The “hatchet-shaped” sternal thought to be a synapomorphy of Styracosterna occurs in two taxa recovered outside that group: Macrogryphosaurus and the unnamed taxon from the Kirkwood Formation of South Africa. Characters associated with quadrupedality are mapped on the phylogeny, indicating a transition from bipedality to quadrupedality occurred in a stepwise manner at the base of Ankylopollexia. Based on synapomorphies of the groups, the major innovations in Ankylopollexia were postcranial, while those of hadrosauroids were centered on dentition and the dentaries. There is a clear faunal succession from the Late Jurassic to Early Cretaceous non-hadrosauroid ankylopollexians to the Late Cretaceous hadrosauroids. Karen Poole. Department of Basic Sciences, New York Institute of Technology College of Osteopathic Medicine at Arkansas State University, Wilson Hall, 2405 Aggie Rd., Jonesboro Arkansas 72401, USA. kpoole@nyit.edu
{"title":"Phylogeny of iguanodontian dinosaurs and the evolution of quadrupedality","authors":"Karen Poole","doi":"10.26879/702","DOIUrl":"https://doi.org/10.26879/702","url":null,"abstract":"Iguanodontians are a large and biogeographically widespread group of dinosaurs, known from every modern continent, with a temporal range from the Late Jurassic through the Late Cretaceous. While the nested hadrosauroids have been studied extensively, the phylogeny of non-hadrosauroid iguanodontians remains less clear. This study presents a character matrix with 323 characters, and both parsimony and time-calibrated Bayesian analyses. While these result in different topologies, they both recover a Thescelosauridae outside of Iguanodontia. Within Iguanodontia, they both recover Muttaburrasaurus and Tenontosaurus as sister taxa to Rhabdodontidae, with a larger group of Gondwanan Rhabdodontoidea (nomen cladi novum) in the Bayesian analysis. A small Dryosauridae forms the sister group to Ankylopollexia, which has Uteodon and Camptosaurus as the most basally branching taxa. Within Styracosterna two distinct clades are recovered: Iguanodontidae, and a group of taxa with robust forelimbs. The holotype of Mantellisaurus is sister to “Dollodon”, supporting the hypothesis that these taxa are synonymous. The “hatchet-shaped” sternal thought to be a synapomorphy of Styracosterna occurs in two taxa recovered outside that group: Macrogryphosaurus and the unnamed taxon from the Kirkwood Formation of South Africa. Characters associated with quadrupedality are mapped on the phylogeny, indicating a transition from bipedality to quadrupedality occurred in a stepwise manner at the base of Ankylopollexia. Based on synapomorphies of the groups, the major innovations in Ankylopollexia were postcranial, while those of hadrosauroids were centered on dentition and the dentaries. There is a clear faunal succession from the Late Jurassic to Early Cretaceous non-hadrosauroid ankylopollexians to the Late Cretaceous hadrosauroids. Karen Poole. Department of Basic Sciences, New York Institute of Technology College of Osteopathic Medicine at Arkansas State University, Wilson Hall, 2405 Aggie Rd., Jonesboro Arkansas 72401, USA. kpoole@nyit.edu","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69155833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guillem Orlandi-Oliveras, M. Köhler, J. Clavel, R. Scott, Serdar Mayda, T. Kaya, G. Merceron
The adaptive radiation of hipparionins after their Old World dispersal was linked with a trend towards smaller body sizes. The appearance of the small-sized forms has usually been associated to open environments and grazing diets. A recent approach, moreover, highlights the role of life history modifications related to habitat conditions as triggers of their size shifts. Here, we test the relationship between hipparionin size and diet analyzing the dental microwear textures of different-sized hipparionins from Vallesian and Turolian circum-Mediterranean localities. Our results show that hipparionins were mainly mixed-feeders and that there was no general link between body size and diet. However, we identified broader feeding spectra in western Mediterranean smaller forms and specialized grazing diets in larger ones, a differentiation not found in the eastern Mediterranean hipparionins. At odds with the notion of more open habitats eastward, we detected a larger browsing component in eastern hipparionin diets. The consumption by extant equids of more woody browse during the dry season us to propose a greater seasonality as a possible cause. Considering the argu-able role of external abrasives on the microwear, another interpretation might involve the presence of more grit in the eastern opener habitats. Interestingly, we found that sympatric hipparionins tend to have similar feeding habits, which points to the fact that their diets were influenced by the local environment. Our results, then, suggest that the small size of some hipparionins resulted from different selective pressures rather than to a general adaptation to increasing habitat opening.
{"title":"Feeding strategies of circum‑Mediterranean hipparionins during the late Miocene: Exploring dietary preferences related to size through dental microwear analysis","authors":"Guillem Orlandi-Oliveras, M. Köhler, J. Clavel, R. Scott, Serdar Mayda, T. Kaya, G. Merceron","doi":"10.26879/990","DOIUrl":"https://doi.org/10.26879/990","url":null,"abstract":"The adaptive radiation of hipparionins after their Old World dispersal was linked with a trend towards smaller body sizes. The appearance of the small-sized forms has usually been associated to open environments and grazing diets. A recent approach, moreover, highlights the role of life history modifications related to habitat conditions as triggers of their size shifts. Here, we test the relationship between hipparionin size and diet analyzing the dental microwear textures of different-sized hipparionins from Vallesian and Turolian circum-Mediterranean localities. Our results show that hipparionins were mainly mixed-feeders and that there was no general link between body size and diet. However, we identified broader feeding spectra in western Mediterranean smaller forms and specialized grazing diets in larger ones, a differentiation not found in the eastern Mediterranean hipparionins. At odds with the notion of more open habitats eastward, we detected a larger browsing component in eastern hipparionin diets. The consumption by extant equids of more woody browse during the dry season us to propose a greater seasonality as a possible cause. Considering the argu-able role of external abrasives on the microwear, another interpretation might involve the presence of more grit in the eastern opener habitats. Interestingly, we found that sympatric hipparionins tend to have similar feeding habits, which points to the fact that their diets were influenced by the local environment. Our results, then, suggest that the small size of some hipparionins resulted from different selective pressures rather than to a general adaptation to increasing habitat opening.","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69156597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Amphibians and squamate reptiles from the late Miocene of Fălciu (Eastern Romania)","authors":"V. Codrea, Marian Bordeianu, M. Venczel","doi":"10.26879/1156","DOIUrl":"https://doi.org/10.26879/1156","url":null,"abstract":",","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69146939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dayou Zhai, Mark Williams, D. Siveter, D. Siveter, T. Harvey, Robert S. Sansom, Huijuan Mai, Run-Bang Zhou, X. Hou
Micro-CT scanning reveals unprecedented three-dimensional soft anatomy of the early Cambrian (Epoch 2, Age 3) euarthropod Chuandianella ovata. We interpret the presence of an elongate, antenniform first appendage, and a short uniramous second appendage, followed by 10 homonomous biramous appendages comprising a short paddle-shaped exopod and a unique feather-like limb-branch with at least 27 podomeres each of which bears a long blade-like endite with a short terminal seta: we interpret this as the endopod. Alternative interpretations, that these limbs might represent an epipod+basipod or epipod+exopod arrangement, are unlikely, in that they would require either the complete reduction of the exopod or the endopod. We also find no evidence for head appendage morphologies that would support a more crownward position, for example among pancrustaceans, that has previously been suggested for
{"title":"Chuandianella ovata: An early Cambrian stem euarthropod with feather-like appendages","authors":"Dayou Zhai, Mark Williams, D. Siveter, D. Siveter, T. Harvey, Robert S. Sansom, Huijuan Mai, Run-Bang Zhou, X. Hou","doi":"10.26879/1172","DOIUrl":"https://doi.org/10.26879/1172","url":null,"abstract":"Micro-CT scanning reveals unprecedented three-dimensional soft anatomy of the early Cambrian (Epoch 2, Age 3) euarthropod Chuandianella ovata. We interpret the presence of an elongate, antenniform first appendage, and a short uniramous second appendage, followed by 10 homonomous biramous appendages comprising a short paddle-shaped exopod and a unique feather-like limb-branch with at least 27 podomeres each of which bears a long blade-like endite with a short terminal seta: we interpret this as the endopod. Alternative interpretations, that these limbs might represent an epipod+basipod or epipod+exopod arrangement, are unlikely, in that they would require either the complete reduction of the exopod or the endopod. We also find no evidence for head appendage morphologies that would support a more crownward position, for example among pancrustaceans, that has previously been suggested for","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69147780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Greenwalt, D. Amorim, M. Hauser, P. Kerr, Scott M. Fitzgerald, S. Winterton, J. Cumming, N. Evenhuis, B. Sinclair
{"title":"Diptera of the Middle Eocene Kishenehn Formation II","authors":"D. Greenwalt, D. Amorim, M. Hauser, P. Kerr, Scott M. Fitzgerald, S. Winterton, J. Cumming, N. Evenhuis, B. Sinclair","doi":"10.26879/1215","DOIUrl":"https://doi.org/10.26879/1215","url":null,"abstract":"","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69147936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Pygocephalomorphan crustaceans further emphasise the similarities between the Carboniferous Piesberg quarry in Germany and the Mazon Creek Lagerstätte in North America","authors":"P. Pazinato, C. Haug, A. Leipner, J. Haug","doi":"10.26879/1051","DOIUrl":"https://doi.org/10.26879/1051","url":null,"abstract":"","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69147083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fossil and extant representatives of Enteropneusta play an important role in the interpretation of early evolution of animals, such as echinoderms, hemichordates and chordates. However, remains of fossil Enteropneusta are rare. Re-examination of available specimens of organic tubes of the Ordovician putative green alga Krejciella putzkeri Obrhel 1968 does not show any morphological difference from the Cambrian Margaretia dorus Walcott, 1931. The latter species has been recently interpreted as an organic tube produced and inhabited by the worm-like enteropneust hemichordate Oesia disjuncta Walcott, 1911. However, the absence of the subterranean lateral extension in Ordovician specimens excludes the synonymy of Krejciella and Margaretia . Geographic distribution of Cambrian organic tubes classified as Margaretia Walcott, 1931 indicates a possible latitudinal control, as all occurrences are apparently restricted to tropical and subtropical belts when plotted in Cambrian palaeogeographic maps. In comparison, the occurrence of the herein studied specimens of Krejciella is restricted to cold-water localities of West Gondwana. The micropalaeontological analy-sis of a rock sample bearing one specimen of Krejciella shows the presence of moder-ately preserved chitinozoans, including the zonal species Linochitina pissotensis . This taxon is, for the first time, documented from the Prague Basin and determines the Mid-dle/Late Ordovician boundary interval of the analysed sample. The herein studied specimens of Krejciella extend the record of organic tubes produced by enteropneust hemichordates both stratigraphically and palaeogeographically to the Middle/Late Ordovician cold-water area.
{"title":"Putative Ordovician green alga Krejciella reinterpreted as enteropneust hemichordate tube (Czech Republic)","authors":"O. Fatka, J. Vodička","doi":"10.26879/1185","DOIUrl":"https://doi.org/10.26879/1185","url":null,"abstract":"Fossil and extant representatives of Enteropneusta play an important role in the interpretation of early evolution of animals, such as echinoderms, hemichordates and chordates. However, remains of fossil Enteropneusta are rare. Re-examination of available specimens of organic tubes of the Ordovician putative green alga Krejciella putzkeri Obrhel 1968 does not show any morphological difference from the Cambrian Margaretia dorus Walcott, 1931. The latter species has been recently interpreted as an organic tube produced and inhabited by the worm-like enteropneust hemichordate Oesia disjuncta Walcott, 1911. However, the absence of the subterranean lateral extension in Ordovician specimens excludes the synonymy of Krejciella and Margaretia . Geographic distribution of Cambrian organic tubes classified as Margaretia Walcott, 1931 indicates a possible latitudinal control, as all occurrences are apparently restricted to tropical and subtropical belts when plotted in Cambrian palaeogeographic maps. In comparison, the occurrence of the herein studied specimens of Krejciella is restricted to cold-water localities of West Gondwana. The micropalaeontological analy-sis of a rock sample bearing one specimen of Krejciella shows the presence of moder-ately preserved chitinozoans, including the zonal species Linochitina pissotensis . This taxon is, for the first time, documented from the Prague Basin and determines the Mid-dle/Late Ordovician boundary interval of the analysed sample. The herein studied specimens of Krejciella extend the record of organic tubes produced by enteropneust hemichordates both stratigraphically and palaeogeographically to the Middle/Late Ordovician cold-water area.","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69148015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Matthew M. Davis, Benjamin D. Nye, G. Sinatra, W. Swartout, Molly Sjӧberg, Molly A. Porter, David Nelson, Alana A. U. Kennedy, Imogen Herrick, Danaan DeNeve Weeks, Emily Lindsey
Paleoart is an important medium that communicates scientific understanding about prehistoric life to both the public and researchers. However, despite its broad influence, the scientific and aesthetic decisions that go into paleoart are rarely described in formal academic literature or subjected to peer review. This is unfortunate, as paleoart can easily create and perpetuate misconceptions that are carried through generations of iterative popular media. As an example of what we hope will become a standard article type in paleontological journals, we describe the process and latest scientific research used to develop 13 new paleoart reconstructions of Ice Age animals found in the La Brea Tar Pits, including the saber-toothed cat, dire wolf, and teratorn. We adopted a stylized low polygon aesthetic for these three-dimensional (3D), animated virtual models both to support learning objectives and to optimize performance for smartphone based augmented reality (AR) experiences. We encourage all researchers to follow the example of this article by publishing paleoart descriptions for any major new work that, at a minimum, reference the aesthetic and scientific reasoning behind general posture and proportions, gross appearance of soft tissues, coloration, and behavior.
{"title":"Designing scientifically-grounded paleoart for augmented reality at La Brea Tar Pits","authors":"Matthew M. Davis, Benjamin D. Nye, G. Sinatra, W. Swartout, Molly Sjӧberg, Molly A. Porter, David Nelson, Alana A. U. Kennedy, Imogen Herrick, Danaan DeNeve Weeks, Emily Lindsey","doi":"10.26879/1191","DOIUrl":"https://doi.org/10.26879/1191","url":null,"abstract":"Paleoart is an important medium that communicates scientific understanding about prehistoric life to both the public and researchers. However, despite its broad influence, the scientific and aesthetic decisions that go into paleoart are rarely described in formal academic literature or subjected to peer review. This is unfortunate, as paleoart can easily create and perpetuate misconceptions that are carried through generations of iterative popular media. As an example of what we hope will become a standard article type in paleontological journals, we describe the process and latest scientific research used to develop 13 new paleoart reconstructions of Ice Age animals found in the La Brea Tar Pits, including the saber-toothed cat, dire wolf, and teratorn. We adopted a stylized low polygon aesthetic for these three-dimensional (3D), animated virtual models both to support learning objectives and to optimize performance for smartphone based augmented reality (AR) experiences. We encourage all researchers to follow the example of this article by publishing paleoart descriptions for any major new work that, at a minimum, reference the aesthetic and scientific reasoning behind general posture and proportions, gross appearance of soft tissues, coloration, and behavior.","PeriodicalId":56100,"journal":{"name":"Palaeontologia Electronica","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69148129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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