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1
Cleal, Christopher J., and Barry A. Thomas. "Naming of parts: the use of fossil-taxa in palaeobotany." Fossil Imprint 77, no. 1 (2021): 166–86. http://dx.doi.org/10.37520/fi.2021.013.
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Fossil plants are extinct plants whose remains (referred to as plant fossils) are found preserved in sedimentary deposits. Plant fossils are classified using fossil-taxa as defined in the International Code of Nomenclature. Fossil-taxa differ conceptually from taxa of living plants in that they often do not refer to whole organisms, but to the remains of one or more parts of the parent organism, in one or more preservational states. There can be complications when two parts of a plant are shown to be connected, or when two preservational states are correlated, and to avoid disrupting the wider palaeobotanical taxonomy it is often best to keep the fossil-taxa separate. Extinct fossil plants reconstructed by piecing together the plant fossils are best not given formal Linnean taxonomic names. There can also be problems using living plant taxa for fossils, even when there is a close morphological similarity of particular plant parts. Fossil-taxa for different plant parts can reflect different taxonomic ranks of the parent plants so care must be taken when using such taxa in floristic or phylogenetic studies. Because of taphonomic factors, a number of “artificial” fossil-taxa have proved useful, despite that they do not fully reflect the systematic positions of the parent plants.
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Heikkilä, Maria, Joël Minet, Andreas Zwick, Anna Hundsdoerfer, Rodolphe Rougerie, and Ian J. Kitching. "Critical re-examination of known purported fossil Bombycoidea (Lepidoptera)." PeerJ 11 (November 10, 2023): e16049. http://dx.doi.org/10.7717/peerj.16049.
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We critically re-examine 17 records of fossils currently assigned to the lepidopteran superfamily Bombycoidea, which includes the silk moths, emperor moths and hawk moths. These records include subfossils, compression and impression fossils, permineralizations and ichnofossils. We assess whether observable morphological features warrant their confident assignment to the superfamily. None of the examined fossils displays characters that allow unequivocal identification as Sphingidae, but three fossils and a subfossil (Mioclanis shanwangiana Zhang, Sun and Zhang, 1994, two fossil larvae, and a proboscis in asphaltum) have combinations of diagnostic features that support placement in the family. The identification of a fossil pupa as Bunaeini (Saturniidae) is well supported. The other fossils that we evaluate lack definitive bombycoid and, in several cases, even lepidopteran characters. Some of these dubious fossils have been used as calibration points in earlier studies casting doubt on the resulting age estimates. All fossil specimens reliably assigned to Bombycoidea are relatively young, the earliest fossil evidence of the superfamily dating to the middle Miocene.
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HEIKKILÄ, MARIA, THOMAS J. SIMONSEN, and M. ALMA SOLIS. "Reassessment of known fossil Pyraloidea (Lepidoptera) with descriptions of the oldest fossil pyraloid and a crambid larva in Baltic amber." Zootaxa 4483, no. 1 (September 20, 2018): 101. http://dx.doi.org/10.11646/zootaxa.4483.1.4.
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The identifications of known fossils currently placed in the lepidopteran superfamily Pyraloidea are critically re-examined. Of the eleven fossils examined, only three are confirmed to show morphological characters supporting placement in the superfamily. These fossils include a crambid larva in Baltic Amber, Baltianania yantarnia, Solis gen. n. et sp. n. and the oldest known fossil pyraloid, Eopyralis morsae Simonsen, gen. n. et sp. n. The third fossil, Glendotricha olgae Kusnezov, 1941, displays apomorphic characters for Pyraloidea, but is shown to be an inclusion in copal, not Baltic amber as had been reported. Seven fossil specimens lack reliable characters and cannot be assigned to Pyraloidea with certainty: Pyralites obscurus Heer, 1856; Pyralites preecei Jarzembowski, 1980; Petisca dryellina Martins-Neto, 1998; three fossil larvae tentatively identified as Pyralidae by Zeuner (1931); and Gallerites keleri Kernbach, 1967. A possible fossil pyraloid in Mizunami amber could not be located in museum collections and available literature does not provide details to assess the validity of the identification. We discuss the contribution of the reliably identified fossils towards better understanding the evolutionary history of Pyraloidea.
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SOHN, JAE-CHEON, CONRAD LABANDEIRA, DONALD DAVIS, and CHARLES MITTER. "An annotated catalog of fossil and subfossil Lepidoptera (Insecta: Holometabola) of the world." Zootaxa 3286, no. 1 (April 30, 2012): 1. http://dx.doi.org/10.11646/zootaxa.3286.1.1.
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In this catalog, we attempt to assemble all fossil records of Lepidoptera described formally or informally in the worldliterature. A total of 667 records dealing with at least 4,568 specimens have been compiled. They include descriptions of131 fossil genera and 229 fossil species, as well as 72 extant genera and 21 extant species to which some of these fossilssupposedly belong or show superficial similarity. Replacement names of two fossil genera are proposed to avoidhomonymy: Baltopsyche Sohn, gen. nov. for Palaeopsyche Sobczyk and Kobbert, 2009 and Netoxena Sohn, gen. nov. forXena Martins-Neto, 1999. New generic combinations are proposed for: Tortrix? destructus Cockerell, 1916, Tortrixflorissantanus Cockerell, 1907, and Tortrix sp. sensu Gravenhorst (1835), all three to Tortricites Kozlov, 1988;Pterophorus oligocenicus Bigot, Nel and Nel, 1986, to Merrifieldia Tutt, 1905; Aporia sp. sensu Branscheid (1969) toPierites Heer, 1849; Noctua spp. sensu Hope (1836) and Lomnicki (1894), both to Noctuites Heer, 1849. Eleven namesimproperly proposed for lepidopteran fossils are invalidated: Baltonides roeselliformis Skalski in Kosmowska-Ceranowicz and Popiolek, 1981; Baltodines Kupryjanowicz, 2001; Barbarothea Scudder, 1890; Lepidopterites Piton,1936; Palaeozygaena Reiss, 1936; Psamateia calipsa Martins-Neto, 2002; Saxibatinca meyi Skalski in Kristensen andSkalski, 1998; Spatalistiforma submerga Skalski, 1976; Thanatites juvenalis Scudder, 1875; Tortricibaltia diakonoffiSkalski, 1976; and Zygaenites Reiss, 1936. An unnecessary subsequent type designation for Pierites Heer, 1849, isdiscussed. A total of 129 records include lepidopteran fossils which cannot be placed in any taxonomic rank. There alsoexist at least 25 fossil records which lack any evidence of the supposed lepidopteran association. Misidentified specimens,including 18 fossil genera, 29 fossil species and 12 unnamed fossils, are excluded from Lepidoptera. All the knownlepidopteran fossils are annotated by fossil type, specimen deposition, excavation locality, association with plants when present, and geological age. A bibliographic list of lepidopteran fossils is provided.
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Near, Thomas J., and Michael J. Sanderson. "Assessing the quality of molecular divergence time estimates by fossil calibrations and fossil–based model selection." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 359, no. 1450 (October 29, 2004): 1477–83. http://dx.doi.org/10.1098/rstb.2004.1523.
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Estimates of species divergence times using DNA sequence data are playing an increasingly important role in studies of evolution, ecology and biogeography. Most work has centred on obtaining appropriate kinds of data and developing optimal estimation procedures, whereas somewhat less attention has focused on the calibration of divergences using fossils. Case studies with multiple fossil calibration points provide important opportunities to examine the divergence time estimation problem in new ways. We discuss two cross–validation procedures that address different aspects of inference in divergence time estimation. ‘Fossil cross–validation’ is a procedure used to identify the impact of different individual calibrations on overall estimation. This can identify fossils that have an exceptionally large error effect and may warrant further scrutiny. ‘Fossil–based model cross–validation’ is an entirely different procedure that uses fossils to identify the optimal model of molecular evolution in the context of rate smoothing or other inference methods. Both procedures were applied to two recent studies: an analysis of monocot angiosperms with eight fossil calibrations and an analysis of placental mammals with nine fossil calibrations. In each case, fossil calibrations could be ranked from most to least influential, and in one of the two studies, the fossils provided decisive evidence about the optimal molecular evolutionary model.
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Bush, Andrew M., and Gwen M. Daley. "Comparative Paleoecology of Fossils and Fossil Assemblages." Paleontological Society Papers 14 (October 2008): 289–317. http://dx.doi.org/10.1017/s108933260000173x.
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Generating and testing hypotheses is an integral part of any science, and some of the most stimulating paleobiological hypotheses of the past few decades relate to the ecological properties of fossils or fossil assemblages. Here, we outline recent methods for framing paleoecological questions that should facilitate the further quantitative evaluation of paleoecological hypotheses. First, we describe theoretical ecospaces, which are frameworks for classifying the ecologic properties of individuals or species based on multiple characters. We discuss the utility of theoretical ecospace in understanding evolutionary constraints and biodiversification, among other topics. Second, we discuss the reconstruction of high-resolution paleoecological gradients using ecological ordination techniques. Ordination can help uncover the paleoenvironmental factors that controlled fossil assemblage composition, track these factors through time, and evaluate the environmental and ecological context of major biotic changes. As an example, we present a new gradient analysis of the Yorktown Formation (Pliocene) of Virginia in which substrate and disturbance controlled molluscan assemblage composition. As a further example, we ordinate samples of mid-Paleozoic and late Cenozoic marine fossil assemblages based on their ecological content (as determined using a theoretical ecospace) to test whether the same environmental and ecological factors controlled the distribution of ecological lifestyles in both time intervals, despite the many differences between them. Although depth-related variation is evident in both data sets, the Cenozoic samples show stronger evidence of environmental control on ecologic content within depth zones. In contrast, Paleozoic gradients are consistent with a more random component in assemblage content. These analyses are quite preliminary, however, and should be verified with more extensive data.
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Buffetaut, Eric. "Minor Title Change: Fossils Becomes Fossil Studies." Fossil Studies 1, no. 1 (December 20, 2023): 76. http://dx.doi.org/10.3390/fossils1010008.
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Sappenfield, Aaron, Mary L. Droser, and James G. Gehling. "Problematica, trace fossils, and tubes within the Ediacara Member (South Australia): redefining the ediacaran trace fossil record one tube at a time." Journal of Paleontology 85, no. 2 (March 2011): 256–65. http://dx.doi.org/10.1666/10-068.1.
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Ediacaran trace fossils are becoming an increasingly less common component of the total Precambrian fossil record as structures previously interpreted as trace fossils are reinterpreted as body fossils by utilizing qualitative criteria. Two morphotypes, Form E and Form F of Glaessner (1969), interpreted as trace fossils from the Ediacara Member of the Rawnsley Quartzite in South Australia are shown here to be body fossils of a single, previously unidentified tubular constructional morphology formally described herein as Somatohelix sinuosus n. gen. n. sp. S. sinuosus is 2-7 mm wide and 3-14 cm long and is preserved as sinusoidal casts and molds on the base of beds. Well-preserved examples of this fossil preserve distinct body fossil traits such as folding, current alignment, and potential attachment to holdfasts. Nearly 200 specimens of this fossil have been documented from reconstructed bedding surfaces within the Ediacara Member. When viewed in isolated hand sample, many of these specimens resemble ichnofossils. However, the ability to view large quantities of reassembled and successive bedding surfaces within specific outcrops of the Ediacara Member provides a new perspective, revealing that isolated specimens of rectilinear grooves on bed bases are not trace fossils but are poorly preserved specimens of S. sinuosus. Variation in the quality and style of preservation of S. sinuosus on a single surface and the few distinct characteristics preserved within this relatively indistinct fossil also provides the necessary data required to define a taphonomic gradient for this fossil. Armed with this information, structures which have been problematic in the past can now be confidently identified as S. sinuosus based on morphological criteria. This suggests that the original organism that produced this fossil was a widespread and abundant component of the Ediacaran ecosystem.
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Walker, S. E. "Criteria for recognizing marine hermit crabs in the fossil record using gastropod shells." Journal of Paleontology 66, no. 4 (July 1992): 535–58. http://dx.doi.org/10.1017/s0022336000024410.
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Hermit crabs have left a rich fossil legacy of epi- and endobionts that bored or encrusted hermit crab-inhabited shells in specific ways. Much of this rich taphonomic record, dating from the middle Jurassic, has been overlooked. Biological criteria to recognize hermitted shells in the fossil record fall within two major categories: 1) massive encrustations, such as encrusting bryozoans; and 2) subtle, thin encrustations, borings, or etchings that surround or penetrate the aperture of the shell. Massive encrustations are localized in occurrence, whereas subtle trace fossils and body fossils are common, cosmopolitan, and stratigraphically long-ranging. Important trace fossils and body fossils associated with hermit crabs are summarized here, with additional new fossil examples from the eastern Gulf Coast.Helicotaphrichnus, a unique hermit crab-associated trace fossil, is reported from the Eocene of Mississippi, extending its stratigraphic range from the Pleistocene of North America and the Miocene of Europe.
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Husien, N., A. Aryanto, Erwin, and AS Budi. "Characteristics of Wood Fossils From Bengkinang Village Kutai Kartanegara Regency." IOP Conference Series: Earth and Environmental Science 1282, no. 1 (December 1, 2023): 012031. http://dx.doi.org/10.1088/1755-1315/1282/1/012031.
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Abstract Fossil wood is petrified wood in which all the organic material has been replaced by minerals (silica and a type of quartz), while preserving the structure of the wood. The purpose of this study was to determine the macroscopic characteristics of wood fossils in general, including their specific gravity, hardness, color, and anatomical features. This research encompassed a survey of fossil discovery locations, the creation of macroscopic wood fossil samples, observation of their macroscopic characteristics, and the measurement of wood hardness as well as the calculation of wood fossil density. The results revealed that the characteristics of the surface cross-section of the fossil samples were dominated by light brown, dark brown, and whitish gray colors. The macro characteristics of the samples exhibited a typical hardwood plant cell structure, characterized by vessels (pores). Unlike previously discovered wood fossils in this area, the wood fossil has axial intercellular canals. The recorded hardness value on the Mohs scale was 5, and the density was measured at 2.7.
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BABCOCK, LOREN E. "Asymmetry in the fossil record." European Review 13, S2 (August 22, 2005): 135–43. http://dx.doi.org/10.1017/s1062798705000712.
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Asymmetry is a fundamental aspect of the biology of all organisms, and has a deep evolutionary history. The fossil record contains evidence of both morphological and behavioural asymmetries. Morphological asymmetry is most commonly expressed as conspicuous, directional asymmetry (either lateral asymmetry or spiral asymmetry) in body fossils. Few examples of fluctuating asymmetry, a form of subtle asymmetry, have been documented from fossils. Body fossil evidence indicates that morphological asymmetry dates to the time of the appearance of the first life on Earth (Archaean Eon). Behavioural asymmetry can be assumed to have been concomitant with conspicuous morphological asymmetry, but more direct evidence is in the form of trace fossils. Trace fossil evidence suggests that behavioural asymmetry, including nervous system lateralization, was in existence by the beginning of the Palaeozoic Era.
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NICOLI, LAURA. "The fossil record of Ceratophrys Wied-Neuwied (Anura: Ceratophryidae): a revision and update of fossil South American horned frogs." Zootaxa 4658, no. 1 (August 21, 2019): 37–68. http://dx.doi.org/10.11646/zootaxa.4658.1.2.
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Ceratophrys is the most diverse and widely distributed genus of Ceratophryidae, the clade of South American horned frogs. Numerous anuran fossil remains, including several fossil species, have been assigned to this genus. However, this seemingly extensive fossil record is problematic because several of the fossils are not properly identified and most of the taxonomic assignations are not justified. The present study traces all the fossil material attributed to Ceratophrys, clarifying, when possible, institutional allocations. Each of the remains was examined and its taxonomic assignation revisited, based on the morphology and possible synapomorphies of the genus, including its living species. Numerous fossils were properly identified and assigned with certainty to Ceratophrys. Only one fossil species, Ceratophrys ameghinorum, is considered valid. This information, along with recently reported evidence of fossil Ceratophrys, is briefly summarized to serve as a practical reference for the entire known fossil record of the genus. The fossil record is not especially informative about the evolution or distribution pattern of Ceratophrys, because most of the remains are relatively young (post-Miocene), collected within the present distribution of the genus, and morphologically consistent with that of the extant species. However, some useful information has emerged. The presence of Ceratophrys is well documented since the Neogene in the Pampean Region of South America. The single valid fossil species, Ceratophrys ameghinorum, possesses a unique combination of characters that reflects a mixture of characters observed in different clades of the genus; thus, resolution of its phylogentic position will inform our understanding of the evolution of the genus. The paleoenvironmental significance of some Ceratophrys fossils is also discussed, addressing the wide, but incompletely known current distribution and environmental tolerance of the genus.
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dos Reis, Mario, Philip C. J. Donoghue, and Ziheng Yang. "Neither phylogenomic nor palaeontological data support a Palaeogene origin of placental mammals." Biology Letters 10, no. 1 (January 2014): 20131003. http://dx.doi.org/10.1098/rsbl.2013.1003.
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O'Leary et al . (O'Leary et al. 2013 Science 339 , 662–667. ( doi:10.1126/science.1229237 )) performed a fossil-only dating analysis of mammals, concluding that the ancestor of placentals post-dated the Cretaceous–Palaeogene boundary, contradicting previous palaeontological and molecular studies that placed the ancestor in the Cretaceous. They incorrectly used fossil ages as species divergence times for crown groups, while in fact the former should merely form minimum-age bounds for the latter. Statistical analyses of the fossil record have shown that crown groups are significantly older than the oldest ingroup fossil, so that fossils do not directly reflect the true ages of clades. Here, we analyse a 20 million nucleotide genome-scale alignment in conjunction with a probabilistic interpretation of the fossil ages from O'Leary et al. Our combined analysis of fossils and molecules demonstrates that Placentalia originated in the Cretaceous.
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Nel, André, and Romain Garrouste. "First semi-aquatic bugs Mesoveliidae and Hebridae (Hemiptera: Heteroptera: Gerromorpha) in Miocene Dominican amber." Insect Systematics & Evolution 41, no. 2 (2010): 93–102. http://dx.doi.org/10.1163/187631210x496822.
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AbstractTwo new semiaquatic bugs of the families Mesoveliidae and Gerridae are described from the Middle Miocene Dominican amber, Mesovelia dominicana sp.n. and Miohebrus anderseni gen.n., sp.n. The former is the first fossil record of the extant genus Mesovelia and the second described fossil of the family Mesoveliidae (the first mesoveliid fossil record was from undescribed fossils in French Cretaceous amber). The latter is the second described fossil Hebridae.
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Colleary, Caitlin, Andrei Dolocan, James Gardner, Suresh Singh, Michael Wuttke, Renate Rabenstein, Jörg Habersetzer, et al. "Chemical, experimental, and morphological evidence for diagenetically altered melanin in exceptionally preserved fossils." Proceedings of the National Academy of Sciences 112, no. 41 (September 28, 2015): 12592–97. http://dx.doi.org/10.1073/pnas.1509831112.
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In living organisms, color patterns, behavior, and ecology are closely linked. Thus, detection of fossil pigments may permit inferences about important aspects of ancient animal ecology and evolution. Melanin-bearing melanosomes were suggested to preserve as organic residues in exceptionally preserved fossils, retaining distinct morphology that is associated with aspects of original color patterns. Nevertheless, these oblong and spherical structures have also been identified as fossilized bacteria. To date, chemical studies have not directly considered the effects of diagenesis on melanin preservation, and how this may influence its identification. Here we use time-of-flight secondary ion mass spectrometry to identify and chemically characterize melanin in a diverse sample of previously unstudied extant and fossil taxa, including fossils with notably different diagenetic histories and geologic ages. We document signatures consistent with melanin preservation in fossils ranging from feathers, to mammals, to amphibians. Using principal component analyses, we characterize putative mixtures of eumelanin and phaeomelanin in both fossil and extant samples. Surprisingly, both extant and fossil amphibians generally exhibit melanosomes with a mixed eumelanin/phaeomelanin composition rather than pure eumelanin, as assumed previously. We argue that experimental maturation of modern melanin samples replicates diagenetic chemical alteration of melanin observed in fossils. This refutes the hypothesis that such fossil microbodies could be bacteria, and demonstrates that melanin is widely responsible for the organic soft tissue outlines in vertebrates found at exceptional fossil localities, thus allowing for the reconstruction of certain aspects of original pigment patterns.
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Rule, James Patrick, Gustavo Burin, and Travis Park. "A quantitative test of the “Ecomorphotype Hypothesis” for fossil true seals (Family Phocidae)." PeerJ 12 (June 19, 2024): e17592. http://dx.doi.org/10.7717/peerj.17592.
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The fossil record of true seals (Family Phocidae) is mostly made up of isolated bones, some of which are type specimens. Previous studies have sought to increase referral of non-overlapping and unrelated fossils to these taxa using the ‘Ecomorphotype Hypothesis’, which stipulates that certain differences in morphology between taxa represent adaptations to differing ecology. On this basis, bulk fossil material could be lumped to a specific ecomorphotype, and then referred to species in that ecomorphotype, even if they are different bones. This qualitative and subjective method has been used often to expand the taxonomy of fossil phocids, but has never been quantitatively tested. We test the proposed ecomorphotypes using morphometric analysis of fossil and extant northern true seal limb bones, specifically principal components analysis and discriminant function analysis. A large amount of morphological overlap between ecomorphotypes, and poor discrimination between them, suggests that the ‘Ecomorphotype Hypothesis’ is not a valid approach. Further, the analysis failed to assign fossils to ecomorphotypes designated in previous studies, with some fossils from the same taxa being designated as different ecomorphotypes. The failure of this approach suggests that all fossils referred using this method should be considered to have unknown taxonomic status. In light of this, and previous findings that phocid limb bones have limited utility as type specimens, we revise the status of named fossil phocid species. We conclude that the majority of named fossil phocid taxa should be considered nomina dubia.
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Torres, Jesús M., Concepción Borja, Luis Gibert, Francesc Ribot, and Enrique G. Olivares. "Twentieth-Century Paleoproteomics: Lessons from Venta Micena Fossils." Biology 11, no. 8 (August 6, 2022): 1184. http://dx.doi.org/10.3390/biology11081184.
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Proteomics methods can identify amino acid sequences in fossil proteins, thus making it possible to determine the ascription or proximity of a fossil to other species. Before mass spectrometry was used to study fossil proteins, earlier studies used antibodies to recognize their sequences. Lowenstein and colleagues, at the University of San Francisco, pioneered the identification of fossil proteins with immunological methods. His group, together with Olivares’s group at the University of Granada, studied the immunological reactions of proteins from the controversial Orce skull fragment (VM-0), a 1.3-million-year-old fossil found at the Venta Micena site in Orce (Granada province, southern Spain) and initially assigned to a hominin. However, discrepancies regarding the morphological features of the internal face of the fossil raised doubts about this ascription. In this article, we review the immunological analysis of the proteins extracted from VM-0 and other Venta Micena fossils assigned to hominins and to other mammals, and explain how these methods helped to determine the species specificity of these fossils and resolve paleontological controversies.
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Kidwell, Susan, and J. John Sepkoski. "The Nature of the Fossil Record." Paleontological Society Special Publications 9 (1999): 61–76. http://dx.doi.org/10.1017/s2475262200014015.
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The term “fossil record” is used in two ways: either the totality of fossils preserved in all rocks or the sum of human knowledge of those fossils. In either case, the term carries the connotation also of the geologic context of the fossils–their distribution in time and space and their relationship to the enclosing rock. One of the primary scientific interests in the fossil record is learning about the history of life and the processes of large-scale transformation, or evolution, in the forms, diversities, and biological interactions of life.
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Puttick, Mark N. "Partially incorrect fossil data augment analyses of discrete trait evolution in living species." Biology Letters 12, no. 8 (August 2016): 20160392. http://dx.doi.org/10.1098/rsbl.2016.0392.
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Ancestral state reconstruction of discrete character traits is often vital when attempting to understand the origins and homology of traits in living species. The addition of fossils has been shown to alter our understanding of trait evolution in extant taxa, but researchers may avoid using fossils alongside extant species if only few are known, or if the designation of the trait of interest is uncertain. Here, I investigate the impacts of fossils and incorrectly coded fossils in the ancestral state reconstruction of discrete morphological characters under a likelihood model. Under simulated phylogenies and data, likelihood-based models are generally accurate when estimating ancestral node values. Analyses with combined fossil and extant data always outperform analyses with extant species alone, even when around one quarter of the fossil information is incorrect. These results are especially pronounced when model assumptions are violated, such as when there is a trend away from the root value. Fossil data are of particular importance when attempting to estimate the root node character state. Attempts should be made to include fossils in analysis of discrete traits under likelihood, even if there is uncertainty in the fossil trait data.
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Donoghue, Philip C. J., and Ziheng Yang. "The evolution of methods for establishing evolutionary timescales." Philosophical Transactions of the Royal Society B: Biological Sciences 371, no. 1699 (July 19, 2016): 20160020. http://dx.doi.org/10.1098/rstb.2016.0020.
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The fossil record is well known to be incomplete. Read literally, it provides a distorted view of the history of species divergence and extinction, because different species have different propensities to fossilize, the amount of rock fluctuates over geological timescales, as does the nature of the environments that it preserves. Even so, patterns in the fossil evidence allow us to assess the incompleteness of the fossil record. While the molecular clock can be used to extend the time estimates from fossil species to lineages not represented in the fossil record, fossils are the only source of information concerning absolute (geological) times in molecular dating analysis. We review different ways of incorporating fossil evidence in modern clock dating analyses, including node-calibrations where lineage divergence times are constrained using probability densities and tip-calibrations where fossil species at the tips of the tree are assigned dates from dated rock strata. While node-calibrations are often constructed by a crude assessment of the fossil evidence and thus involves arbitrariness, tip-calibrations may be too sensitive to the prior on divergence times or the branching process and influenced unduly affected by well-known problems of morphological character evolution, such as environmental influence on morphological phenotypes, correlation among traits, and convergent evolution in disparate species. We discuss the utility of time information from fossils in phylogeny estimation and the search for ancestors in the fossil record. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’.
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Santucci, Vincent L. "Preserving fossils in the national parks: A history." Earth Sciences History 36, no. 2 (January 1, 2017): 245–85. http://dx.doi.org/10.17704/1944-6178-36.2.245.
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ABSTRACT The fossil record preserved throughout the National Park Service spans more than a billion years and is documented in at least 267 park units. The discovery, collection, study, and resource management of fossils from localities which are currently within parks sometimes predate the establishment of the National Park Service and many of the parks. Public education and interpretation at parks such as Agate Fossil Beds and Tule Springs Fossil Beds national monuments and many other designated areas include information on the rich history of paleontological field work by notable paleontologists undertaken prior to the areas being preserved as national park areas. Another important historical aspect for several dozen parks involves the conservation efforts undertaken by the public and interest groups to preserve and protect these important fossil localities. The evolution of the science and methodologies in paleontology is reflected in the resource management undertaken by the National Park Service and documented in park resource management records and archives, scientific publications, and agency policy. Today the National Park Service celebrates fossils by coordinating the National Fossil Day partnership which helps to promote the scientific and educational value of fossils.
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Stafford, Thomas W., P. E. Hare, Lloyd Currie, A. J. T. Jull, and Douglas Donahue. "Accuracy of North American Human Skeleton Ages." Quaternary Research 34, no. 1 (July 1990): 111–20. http://dx.doi.org/10.1016/0033-5894(90)90076-w.
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AbstractAccelerator mass spectrometry (AMS) radiocarbon dates fail to provide conclusive evidence that all New World human fossils are younger than approximately 11,000 yr. Because fossil bones vary widely in preservation, their radiocarbon dates are not equally accurate. Molecular-level radiocarbon dating, which used individual amino acids to assess fossil diagenesis, revealed that dates on known-age, noncollagenous bone were underestimated by at least 2000 to 9000 yr. The significance is that >11,000-yr-old fossil bones with poor preservation would yield Holocene and not Pleistocene radiocarbon ages, regardless of what chemical pretreatment or 14C counting method was used. Irreplaceable evidence for Pleistocene-age fossils in the New World could be lost if the diagenesis of fossil bones is not evaluated before the bones are radiocarbon dated. In contrast, radiocarbon ages for collagenous fossils can be determined more accurately if 14C is measured in several individual amino acids that are isolated from collagenous bone protein. Molecular-level radiocarbon dating will greatly improve not only the accuracy of chronologies for human migrations and animal extinctions, but of all late Quaternary chronologies that are based upon the 14C dating of fossil proteins.
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Sullivan, Colleen A., and Sarah W. Keenan. "Experimental dissolution of fossil bone under variable pH conditions." PLOS ONE 17, no. 10 (October 13, 2022): e0274084. http://dx.doi.org/10.1371/journal.pone.0274084.
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Fossils exposed at the surface are an integral component of the paleontologic record and provide an archive of past life. However, it is widely known that fossils are not stable indefinitely upon exposure to surface conditions such as physical, chemical, and biological processes, and this last phase of taphonomy is poorly understood. Studies regarding the longevity of fossils subject to weathering, such as acidic precipitation, are absent in the literature. The goal of this study was to experimentally determine vertebrate fossil dissolution rates under variable pH conditions in a controlled laboratory setting. It was hypothesized that fossils would dissolve within acidic solutions and do so at an increasing rate when exposed to increasingly acidic solutions. The experiments were conducted on three fossil vertebrae in triplicate in closed reaction vessels at pH 4, 5, and 6. The fossils were completely submerged for 21 days in a tap water solution with the pH adjusted using 0.1N hydrochloric acid (HCl). Fossil dissolution was quantified by changes to: (1) fossil mass; (2) elemental chemistry of water and fossils with inductively coupled plasma mass spectrometry (ICP-MS); (3) fossil mineralogy with X-ray diffraction (XRD); and (4) histologic structures with thin section analyses. All fossils exhibited mass loss, which increased with decreasing pH conditions, and was greatest under pH 4 (477 to 803 mg loss). The elemental analyses with ICP-MS indicated an increase of both calcium (maximum increase of 315 ppm) and phosphorus (increase of 18 ppm) in aqueous solutions with increasing pH and a loss of those same elements from the fossils (maximum loss of 10 ppm Ca and 6 ppm P). XRD revealed loss of gypsum in all post-dissolution samples. Taken together, the results of ICP-MS and XRD suggest dissolution of the primary mineral phases, including hydroxylapatite, and secondary phases, particularly calcite and gypsum, resulting in an estimated mass loss at pH 4 of 23 to 28 mg per day. Thin section analysis showed degradation of both cortical and trabecular bone in all post-dissolution images, demonstrating physical changes to the fossils as a result of water-rock interactions. These findings constitute the first quantitative analysis of fossil dissolution rates and provide insights into this last stage of taphonomy, addressing a largely understudied potential bias in the vertebrate fossil record.
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Smith, E. F., L. L. Nelson, S. M. Tweedt, H. Zeng, and J. B. Workman. "A cosmopolitan late Ediacaran biotic assemblage: new fossils from Nevada and Namibia support a global biostratigraphic link." Proceedings of the Royal Society B: Biological Sciences 284, no. 1858 (July 12, 2017): 20170934. http://dx.doi.org/10.1098/rspb.2017.0934.
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Owing to the lack of temporally well-constrained Ediacaran fossil localities containing overlapping biotic assemblages, it has remained uncertain if the latest Ediacaran ( ca 550–541 Ma) assemblages reflect systematic biological turnover or environmental, taphonomic or biogeographic biases. Here, we report new latest Ediacaran fossil discoveries from the lower member of the Wood Canyon Formation in Nye County, Nevada, including the first figured reports of erniettomorphs, Gaojiashania , Conotubus and other problematic fossils. The fossils are spectacularly preserved in three taphonomic windows and occur in greater than 11 stratigraphic horizons, all of which are below the first appearance of Treptichnus pedum and the nadir of a large negative δ 13 C excursion that is a chemostratigraphic marker of the Ediacaran–Cambrian boundary. The co-occurrence of morphologically diverse tubular fossils and erniettomorphs in Nevada provides a biostratigraphic link among latest Ediacaran fossil localities globally. Integrated with a new report of Gaojiashania from Namibia, previous fossil reports and existing age constraints, these finds demonstrate a distinctive late Ediacaran fossil assemblage comprising at least two groups of macroscopic organisms with dissimilar body plans that ecologically and temporally overlapped for at least 6 Myr at the close of the Ediacaran Period. This cosmopolitan biotic assemblage disappeared from the fossil record at the end of the Ediacaran Period, prior to the Cambrian radiation.
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Lockley, Martin G. "Tracks and Traces: New Perspectives on Dinosaurian Behavior, Ecology, and Biogeography." Short Courses in Paleontology 2 (1989): 134–45. http://dx.doi.org/10.1017/s2475263000000921.
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Conventional paleontological wisdom holds that there are two major categories of fossil evidence: body fossils (skeletal remains), and trace fossils (including tracks and traces). Ichnology, the study of trace fossils, requires a parallel taxonomy of scientific names (parataxonomy or ichnotaxonomy), like the form taxa of fossil plant remains. This ichnotaxonomy describes a large variety of traces attributable to invertebrates (Hantzschel, 1975) and vertebrates (Haubold, 1984; Leonardi, 1984; Leonardi et al., 1986).
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Unger, Shem, and Mark Rollins. "Find a Fossil and “Choose your own Adventure”." International Journal of Educational Innovation and Research 3, no. 1 (January 5, 2024): 86–96. http://dx.doi.org/10.31949/ijeir.v3i1.7253.
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Science education university curriculum should foster transformative methods of teaching and learning for science majors, including science communication. Pedagogical methods for increasing student awareness of paleontological fossils present challenges as fossils are often presented as preserved remains with little visualizations or reconstructions of fossils. As part of increasing scientific literacy and increasing confidence in professional development skills, student presentations can provide an avenue for promoting these necessary skills for biology majors. This study reports on a short multi-week activity whereby students A) selected a fossil to investigate, B) completed a one to two slide presentation on their fossil of choice, and C) presented their fossil overview to their peers in a lecture classroom. Post-activity surveys and reflections indicate that students found this activity engaging, a fun method for learning about a large diversity of fossils important to evolution, and finally, enjoyed selecting their own fossil. Therefore, allowing students to present on fossils and the evolutionary story they each tell may have increased engagement, piqued interest, and enabled students to both learn and focus on taxa of interest to them personally. We recommend science educators incorporate short, low risk presentations as a learning tool in biology courses to “bring fossils alive” and increase engagement among biology students by promoting student science communication.
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BOSKOVIC, DANILO S., URIEL L. VIDAL, KEVIN E. NICK, RAUL ESPERANTE, LEONARD R. BRAND, KENNETH R. WRIGHT, LAWRENCE B. SANDBERG, and BETHANIA C. T. SIVIERO. "STRUCTURAL AND PROTEIN PRESERVATION IN FOSSIL WHALE BONES FROM THE PISCO FORMATION (MIDDLE-UPPER MIOCENE), PERU." PALAIOS 36, no. 4 (April 30, 2021): 155–64. http://dx.doi.org/10.2110/palo.2020.032.
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ABSTRACT Microstructural and biomolecular preservation is reported in fossils as old as the Triassic. Such preservation suggests unusual taphonomic conditions. We collected fragments of fossil whale bone from silty, tuffaceous, and diatomaceous rocks of the middle-upper Miocene portion of the Pisco Formation. The whale fossils within the region are generally well-preserved and mostly articulated, including some specimens with in situ baleen. Due to the depositional setting associated with the preservation of these fossils, they could be expected to be favorable candidates for the preservation of cellular microstructures and/or original biomolecules. To test this hypothesis, fossil whale bone fragments were subjected to microscopic analysis and EDTA-mediated demineralization to release extractable materials. Microscopy of partially demineralized fossil bones revealed quartz-permineralized osteocyte-like and vessel-like structures. Protein assay (micro-Bicinchoninic Acid Assay) of the supernatants obtained from demineralized fossils yielded 12 to 19.5 μg of protein per gram of bone. MALDI-TOF analysis of the extracted protein demonstrated the presence of approximately 5 kD molecules in one fossil sample, consistent with the presence of highly fragmented polypeptides. An LC-MS/MS analysis of the fragmentation pattern of the tryptic digest of extracted protein was performed. However, attempted protein identification was unsuccessful. Nevertheless, this study first documents the microstructural preservation with some silicification of the fossil whale bones of the Pisco Formation, and then quantifies extractable protein from these bones. It adds to the growing body of reports of microstructural and organic preservation in fossils.
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Kaliściak, Tomasz. "W poszukiwaniu kwiatu nietoty. „Literatura kopalna” a paleobotanika." Wielogłos, no. 1 (55) (2023): 17–40. http://dx.doi.org/10.4467/2084395xwi.23.002.17990.
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In Search of the Nietota Flower. „Fossil Literature” and Paleobotany The article focuses on the issues of paleontology, the science of plant fossils, with particular emphasis on paleobotanical threads devoted to fossil vegetation, which in the 19th century was closely related to philology, represented both by the science of literature and language. The author extracts the notions of “fossil literature” (Adam Mickiewicz) and “fossil poetry” (Ralph Waldo Emerson), pointing to their particular relationship with “paleobotany of the unconscious” (Kazimierz Wyka), presented from the psychoanalytic perspective (Eduard von Hartmann, Carl Gustav Jung, Charles Baudouin) as an archetype of collective, interspecies memory, reaching back to some common ancestor and root cause reminding us of the eternal coexistence of the organic and the inorganic, plant and animal, human and non-human. The author also draws attention to the ecological and ecocritical aspects of the fossil literature, which he perceives as the trace fossils of human life activity (ichnofossils), which make up the meta-layer of the Anthropocene.
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Kidwell, Susan M., and J. John Sepkoski. "The Nature of the Fossil Record." Paleontological Society Special Publications 11 (2002): 47–62. http://dx.doi.org/10.1017/s2475262200009813.
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The term “fossil record” is used in two ways: to mean either the totality of fossils preserved in all rocks or the sum of human knowledge of those fossils. In both cases, the term carries the connotation also of the geologic context of the fossils—their distribution in time and space and their relationship to the enclosing rock. One of the primary scientific interests of the fossil record is what it can teach us about the history of life and the processes of large-scale transformation, or evolution, in the forms, diversities, and biological interactions of living things.
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DOWELD, ALEXANDER B. "Styrax carranzae, a new name for extant Styrax lanceolatus P.W. Fritsch non Engelhardt (Styracaceae)." Phytotaxa 460, no. 3 (September 25, 2020): 235–36. http://dx.doi.org/10.11646/phytotaxa.460.3.7.
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In revising fossil records of the genus Styrax Linnaeus (1753: 444) for the International Fossil Plant Names Index (IFPNI, 2014 onwards) with the aim of listing all fossil plant species (Doweld 2015, 2016a), it became apparent that a few fossil-species are later illegitimate homonyms of the extant species of Styrax, and their nomenclature was recently resolved by proposing new replacement names for them (Doweld 2016b). However, an additional case of the homonymy of an extant species by a preoccupied name in fossils remained unsettled.
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McMahon, Sean. "Earth's earliest and deepest purported fossils may be iron-mineralized chemical gardens." Proceedings of the Royal Society B: Biological Sciences 286, no. 1916 (November 27, 2019): 20192410. http://dx.doi.org/10.1098/rspb.2019.2410.
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Recognizing fossil microorganisms is essential to the study of life's origin and evolution and to the ongoing search for life on Mars. Purported fossil microbes in ancient rocks include common assemblages of iron-mineral filaments and tubes. Recently, such assemblages have been interpreted to represent Earth's oldest body fossils, Earth's oldest fossil fungi, and Earth's best analogues for fossils that might form in the basaltic Martian subsurface. Many of these putative fossils exhibit hollow circular cross-sections, lifelike (non-crystallographic, constant-thickness, and bifurcate) branching, anastomosis, nestedness within ‘sheaths’, and other features interpreted as strong evidence for a biological origin, since no abiotic process consistent with the composition of the filaments has been shown to produce these specific lifelike features either in nature or in the laboratory. Here, I show experimentally that abiotic chemical gardening can mimic such purported fossils in both morphology and composition. In particular, chemical gardens meet morphological criteria previously proposed to establish biogenicity, while also producing the precursors to the iron minerals most commonly constitutive of filaments in the rock record. Chemical gardening is likely to occur in nature. Such microstructures should therefore not be assumed to represent fossil microbes without independent corroborating evidence.
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Crimes, T. P., and M. L. Droser. "Trace Fossils and Bioturbation: The Other Fossil Record." Annual Review of Ecology and Systematics 23, no. 1 (November 1992): 339–60. http://dx.doi.org/10.1146/annurev.es.23.110192.002011.
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Winarto, Johan Budi, Wilda Aini Nurlathifah, Agustina Djafar, Andy Dharmedy Sipayung, Rahajeng Ayu Permana Sari, and Halmi Insani. "The Surficial Basin Sediment Investigation and Its Concerned Vertebrate Fossils in Sirtwo Island, Western Part of Saguling Dam, West Java, Indonesia." Indonesian Journal of Earth Sciences 2, no. 1 (June 27, 2022): 1–15. http://dx.doi.org/10.52562/injoes.v2i1.288.
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In October 2021, the depreciation of the water level of dam Saguling revealed the surficial sediment where was dam up Citarum river. Sirtwo island and surroundings are part of the body sediment were arisen which is part of the sedimentary facies in the western of Bandung Lake ancient. Several vertebrate fossils were found on Sirtwo island and Pasir Benteng island. The investigation of vertebrate fossils was carried out to understand where are deposited in Bandung lake. The geological survey lead to the recognition of types of lake deposits and was divided into 5 block observations i.e., Block A, Block B, Block C, Block D, and Block E. Geographic information system was used to determine the location points where the fossil was found and is correlated with other location. The fossils fragment is identified as vertebrate fossils i.e., Bovid sp., Rusa sp., and Elephas maximus. The detail of vertebrate fossils type and sediment petrology is under further analysis. The sedimentary facies are lake deposit and is distinguished into 3 sub-facies: 1) volcanic deposit with vertebrate fossil 2) sandstone tuff without vertebrate fossil and 3) sandstone tuff with vertebrate fossil. The age of lithology is estimated between 10.000 till >135.000 Years ago and the depositional environment is interpreted into fan lake, channel, and lake bottom. This study clearly determines lithofacies in the research area which contain vertebrate fossils.
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KATO, MOE. "Crinoids lived around the Cretaceous seeps: the second example from cold-seep deposit in the Yezo Group in Hokkaido, Japan." Zoosymposia 15, no. 1 (October 21, 2019): 88–97. http://dx.doi.org/10.11646/zoosymposia.15.1.10.
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Cold seep deposits are characterized by authigenic carbonates with very low δ13C signatures and specific fossils of chemosynthetic community members. These members are mainly composed of mollusks, whereas only a few occurrences of fossil echinoderms from cold seep deposits have been reported. The information of paleoecology of fossil echinoderms in or near cold seep environments is also sporadic. Allochthonous columnal fossils of an Isocrinina crinoid species were found in a boulder of Cretaceous cold seep carbonate from the Yezo Group in northern Hokkaido. The stable carbon isotope of the fossil crinoid specimens showed very low values, approximately −30‰ (VPDB) or much lower value. The low δ13C signatures of the seep crinoids and their mode of occurrences suggest that the fossil crinoids lived near the seep environment, and they assimilated low δ13C organic particles shifted from there.
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Fikáček, Martin, Sonja Wedmann, and Heiko Schmied. "Diversification of the greater hydrophilines clade of giant water scavenger beetles dated back to the Middle Eocene (Coleoptera:Hydrophilidae:Hydrophilina)." Invertebrate Systematics 24, no. 1 (2010): 9. http://dx.doi.org/10.1071/is09042.
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Fossil representatives of the hydrophilid genera Hydrochara Berthold, 1827, Hydrobiomorpha Blackburn, 1888 and Hydrophilus Geoffroy, 1762 were recorded at the lower Middle Eocene locality Grube Messel in Germany. Four morphospecies were recognised, including Hydrobiomorpha eopalpalis, sp. nov. showing sexually dimorphic maxillary palpomere 2 unknown in any recent or fossil species of the genus. These fossils are the oldest known records of the mentioned genera and indicate a minimum age of 47 million years for the divergence of the Hydrobiomorpha and Hydrophilus clades. Based on these data, we assume that the diversification of the ‘greater hydrophilines’ clade predated the lower Middle Eocene. The fossil record of the subtribe Hydrophilina is briefly reviewed, the reasons of the scarcity or absence of some genera in the fossil record are discussed, and the paleoenviromental significance of the presented fossils is discussed.
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Valencia Giraldo, Yenny Paola, Luis Carlos Escobar Arenas, Juliana Mendoza Ramirez, Daniel Delgado Sierra, and Andrés Leonardo Cárdenas Rozo. "Review of fossiliferous localities at Antioquia department, Colombia." Boletín de Ciencias de la Tierra, no. 40 (July 1, 2016): 46–54. http://dx.doi.org/10.15446/rbct.n40.53748.
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Even though only 11.5% of Antioquia’s area has outcrops of sedimentary rocks, a review of the literature and the development of a digital map of fossil localities (27), allows us to conclude that the region has a great palaeontological potential. The data show that Antioquia’s fossil occurrences date from Ordovician (~ 485.4 to ~ 443.8Ma) to Quaternary (~ 2.6Ma to the Present). Moreover, there are macro-fossils belonging to different phyla (i.e. Chordata, Echinodermata, Hemichordata, Mollusca and Trachaeophyta). The oldest paleofauna in the area, consists of graptolites and trilobites recorded in Paleozoic metasedimentary rocks, whereas marine mollusks and echinoderms compose the major fossil assemblages of the Cretaceous. The paleoflora (i.e. fossil leaves and petrified wood) in the area is associated with to the Amagá Formation (Oligocene - Miocene). Finally, fossils of terrestrial vertebrates (i.e. mastodons and horses) are recorded in Quaternary deposits.
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Gallucci, John E., Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R. Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, and Dennis O. Terry. "Controls on Soft Tissue and Cellular Preservation in Late Eocene and Oligocene Vertebrate Fossils from the White River and Arikaree Groups of Nebraska, South Dakota, and Wyoming." Minerals 14, no. 5 (May 8, 2024): 497. http://dx.doi.org/10.3390/min14050497.
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Previous studies on microtaphonomy have identified multiple types of organic microstructures in fossil vertebrates from a variety of time periods and past environmental settings. This study investigates potential taphonomic, paleoenvironmental, and paleoclimatic controls on soft tissue and cellular preservation in fossil bone. To this end, fifteen vertebrate fossils were studied: eight fossils collected from the Oligocene Sharps Formation of the Arikaree Group in Badlands National Park, South Dakota, and seven fossils from formations in the underlying White River Group, including the Oligocene Brule Formation of Badlands National Park, and the Eocene Chadron Formation of Flagstaff Rim, Wyoming; Toadstool Geologic Park, Nebraska; and Badlands National Park, South Dakota. A portion of each fossil was demineralized to identify any organic microstructures preserved within the fossils. We investigated several factors which may have influenced cellular/soft tissue decay and/or preservation pathways, including taxonomic identity, paleoclimatic conditions, depositional environment, and general diagenetic history (as interpreted through thin section analysis). Soft tissue microstructures were preserved in all fossil samples, and cellular structures morphologically consistent with osteocytes were recovered from 11 of the 15 fossil specimens. Preservation of these microstructures was found to be independent of taxonomy, paleoclimate regime, apatite crystallinity, depositional environment, and general diagenetic history, indicating that biogeochemical reactions operating within microenvironments within skeletal tissues, such as within individual osteocyte lacunae or Haversian canals, may exert stronger controls on soft tissue and biomolecular decay or stabilization than external environmental (or climatic) conditions.
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Poinar Jr, George O. "New fossil nematodes in Dominican and Baltic amber." Nematology 14, no. 4 (2012): 483–88. http://dx.doi.org/10.1163/156854111x612199.
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Four new species of fossil mermithids (Nematoda: Mermithidae) are described from amber: Heydenius arachnius n. sp. from a spider (Arachnida: Araneae) in Dominican amber, H. phasmatophilus n. sp., from a walking stick (Phasmatodea: Phasmatidae) in Baltic amber, H. podenasae n. sp. from a moth (Lepidoptera) in Baltic amber and H. trichorosus n. sp. from a caddis fly (Trichoptera: Leptoceridae) in Baltic amber. With previous descriptions of fossil mermithids from Diptera, Coleoptera, Hymenoptera and Hemiptera, there are now representatives of seven insect orders as hosts of fossil mermithids. With these additional four fossils, the total number of described nematode fossils is now 95, with 70 occurring in amber.
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Warner, Barry G., Helen J. Kubiw, and Paul F. Karrow. "Origin of a postglacial kettle-fill sequence near Georgetown, Ontario." Canadian Journal of Earth Sciences 28, no. 12 (December 1, 1991): 1965–74. http://dx.doi.org/10.1139/e91-178.
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Stratigraphic relationships, radiocarbon dating, and pollen and plant macrofossil analyses establish the origin and developmental history of a kettle near Georgetown, Ontario. The early inorganic sediments contain redeposited fossils, particularly from local vegetation. Fossils in peat younger than 10 000 BP largely represent past wetland plant communities in the basin. Although the fossil record probably began about 1300 years after deglaciation of the site, an additional 1700 years passed before the dead ice block melted; only then did sedimentation and biological activity stabilize in the basin and produce an accurate fossil record of past vegetation. Truncated fossil records, illustrated further here by a pollen diagram from nearby Heart Lake, should be expected from kettle-hole deposits, and the radiocarbon ages and fossils from the earliest parts of such sequences should be interpreted with caution.
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King, Benedict, and Martin Rücklin. "Tip dating with fossil sites and stratigraphic sequences." PeerJ 8 (June 26, 2020): e9368. http://dx.doi.org/10.7717/peerj.9368.
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Tip dating, a method of phylogenetic analysis in which fossils are included as terminals and assigned an age, is becoming increasingly widely used in evolutionary studies. Current implementations of tip dating allow fossil ages to be assigned as a point estimate, or incorporate uncertainty through the use of uniform tip age priors. However, the use of tip age priors has the unwanted effect of decoupling the ages of fossils from the same fossil site. Here we introduce a new Markov Chain Monte Carlo (MCMC) proposal, which allows fossils from the same site to have linked ages, while still incorporating uncertainty in the age of the fossil site itself. We also include an extension, allowing fossil sites to be ordered in a stratigraphic column with age bounds applied only to the top and bottom of the sequence. These MCMC proposals are implemented in a new open-source BEAST2 package, palaeo. We test these new proposals on a dataset of early vertebrate fossils, concentrating on the effects on two sites with multiple acanthodian fossil taxa but wide age uncertainty, the Man On The Hill (MOTH) site from northern Canada, and the Turin Hill site from Scotland, both of Lochkovian (Early Devonian) age. The results show an increased precision of age estimates when fossils have linked tip ages compared to when ages are unlinked, and in this example leads to support for a younger age for the MOTH site compared with the Turin Hill site. There is also a minor effect on the tree topology of acanthodians. These new MCMC proposals should be widely applicable to studies that employ tip dating, particularly when the terminals are coded as individual specimens.
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Kahraman, Nurfeddin. "General properties of elmacik fossil beds and Its importance in view of anatolian paleogeography." New Trends and Issues Proceedings on Humanities and Social Sciences 2, no. 2 (January 12, 2016): 229–38. http://dx.doi.org/10.18844/prosoc.v2i2.449.
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Tefenni Basin, is located in the southwestern part of Burdur Basin. Elmacık village where paleontological excavations was made, is established at the place where Elmacık stream opens to Tefenni basin.     Elmacık fossil beds, were discovered during the geomorphological studies we did in 1997. Lake containing fossil, marsh layers consisting of fillers, are located on the Formation of Burdur. These layers showing different color and texture features, are tilted 10-15 degrees to the east-southeast direction by tectonic movements affecting region. Due to subsidence and rising as a cause of tectonic reasons, this layer series are located at different altitudes. Elmacık fossil beds insitu situation have mostly fossil localities. Secondary fossils are also observed in some layer series. Secondary fossil finds, consists of horn and bone oms belonging to various species lived in earlier periods. Elmacık vertebrate fossil bed, is located between the Neogene fossil beds in Tokmacık town of Isparta province and Özlüce village of Muğla province in south west Anatolia., According to these findings, Elmacık fossil bed shows a bed feature where comparisons can be made in view of the spread and migration of the upper Neogene faunal species. Between 2006 - 2009, excavations were made in five localities in Elmacık fossil beds. Through this excavations, the presence of twelve different macro species were identified in the region, macro proboscidians being in the first place. Among the excavated fossils, defense tooth of South Mamut, has been the largest ivory ever found in Turkey. Palaeontological findings excavated from the Elmacık beds, will be exhibited in a museum of natural history established in the center of Burdur. With new work to be done in the Elmacık fossil beds, withdrawal stages of Burdur Pliocene lake, Pliocene tectonic movements affecting the region and new evidence of Quaternary transition period may also be obtained.   Keywords: Elmacık fossil beds, Burdur Formation, South mammoth, the natural history museum.
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Kocsis, László. "The Elasmobranch Fossil Record of the Indo-Australian Archipelago since the Miocene: A Literature Review and New Discoveries from Northern Borneo." Diversity 16, no. 6 (May 29, 2024): 323. http://dx.doi.org/10.3390/d16060323.
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The Indo-Australian Archipelago (IAA) today exhibits the highest marine biodiversity, which has been evolving since the early Miocene. The existence of this high palaeobiodiversity is attested to by the presence of many fossil invertebrates; however, the region’s fossil fish record is sparse and understudied, which is also the case for cartilaginous fishes. Elasmobranch fossils are dominantly represented by shark and ray teeth in the geological record and can give a quick overview of the composition of the fauna. The first IAA elasmo fossils, shark teeth were described from Java (Indonesia) at the end of the 19th century, and until today, most of the publications are known from this island. In the early and middle of the 20th century, remarkable fossils were also reported from the islands of Madura (NE Java) and Sulawesi, some with detailed taxonomical descriptions. In addition, only sporadic reports on fossil occurrences exist elsewhere from the IAA, but these lack any detailed taxonomic accounts. In 2019 our research group reported a late Miocene elasmobranch fauna from Brunei (Borneo), which is now the most diverse known shallow water fossil assemblage from the entire IAA. This fauna was described from a single fossiliferous outcrop, called Ambug Hill. However, several new localities have been discovered and studied over the years, as a result the number of fossils increased, and their age range extended. Here we provide an overview of these new sites and their elasmobranch fossils, and describe remains from ten taxa among, of which eight are new to the IAA fossil record (Chiloscyllium sp., cf. Hemitriakis sp., Paragaleus sp., Carcharhinus borneensis, C. limbatus, Lamiopsis sp., Scoliodon sp., Rhinobatos sp.). The overall north Bornean elasmo assemblage is then compared with other IAA occurrences. An extended fauna list is given based on literature review and preliminary investigation of the Naturalis Biodiversity Centre collection in Leiden (The Netherlands) where most of the fossil fishes of the early explorations are stored. These assemblages are also briefly summarized, and attention is drawn to some of the unique and thus far unreported taxa (e.g., Dalatias licha).
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ZHURAVLEV, ANDREY YU, JOSÉ ANTONIO GÁMEZ VINTANED, and ANDREY YU IVANTSOV. "First finds of problematic Ediacaran fossil Gaojiashania in Siberia and its origin." Geological Magazine 146, no. 5 (July 2, 2009): 775–80. http://dx.doi.org/10.1017/s0016756809990185.
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AbstractWe describe the first occurrence of the problematic fossil Gaojiashania outside China, in the Ediacaran Yudoma Group of the Siberian Platform. In both areas, Gaojiashania characterizes the lower upper Ediacaran strata and precedes the appearance of Cloudina and other skeletal fossils, which highlights its significance for the Ediacaran subdivision and correlation. Features of this fossil such as indeterminate length, the absence of a distinct growth pattern, and self-avoiding behaviour indicate its trace fossil origin but do not necessarily imply metazoan affinities for its producers. Several organisms including stem-group social amoebozoans and unicellular protists may have been Proterozoic trace fossil producers.
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Zhang, Haichun, and Mathias Harzhauser. "Advanced Research on Fossil Insects." Taxonomy 2, no. 4 (November 25, 2022): 488–90. http://dx.doi.org/10.3390/taxonomy2040031.
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Sato, Takashi, Marjorie Chan, and Allan Ekdale. "Trace fossils and fluvial-lacustrine ichnofacies of the Eocene Uinta and Duchesne River Formations, northern Uinta Basin, Utah." Geology of the Intermountain West 5 (September 18, 2018): 209–26. http://dx.doi.org/10.31711/giw.v5.pp209-226.
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Trace fossil assemblages in a fluvial-lacustrine sequence stratigraphic context hold significant poten-tial for expanding our understanding of environmental controls and continental basin-fill history. The succession of the Eocene Uinta Formation and four members of the Duchesne River Formation is ex¬tremely well-exposed in the Uinta Basin of northeastern Utah, revealing a robust stratigraphic framework to document broad-scale fluvial-lacustrine facies architectures and associated trace fossil assemblages. Greenish- and gray-colored mudstone beds with interbedded tabular sandstone representing lacustrine environments contain the trace fossils Arenicolites and Gordia (= Haplotichnus). In contrast, red mudstone beds with interbedded channelized sandstone representing upstream fluvial and alluvial environments contain a variety of insect trace fossils, including Scoyenia, Ancorichnus, and nest structures. Transitional, interfingering lithologies of wetland or shallow, short-lived lacustrine environments on the alluvial plain contain the trace fossil Steinichnus. Although there are many small-scale (bed-scale) physical sedimen¬tary structures and trace fossils from continental subenvironments, this study focuses on the large-scale (member-scale) change in trace fossil assemblages, with results indicating that the ichnofacies corroborate continental sequence stratigraphic interpretations in a fluvial-lacustrine setting.
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Sato, Takashi, Marjorie A. Chan, and Allan A. Ekdale. "Trace fossils and fluvial-lacustrine Ichnofacies of the Eocene Uinta and Duchesne River Formations, northern Uinta Basin, Utah." Geology of the Intermountain West 5 (September 29, 2018): 209–26. http://dx.doi.org/10.31711/giw.v5i0.27.
Full textAbstract:
Trace fossil assemblages in a fluvial-lacustrine sequence stratigraphic context hold significant poten-tial for expanding our understanding of environmental controls and continental basin-fill history. The succession of the Eocene Uinta Formation and four members of the Duchesne River Formation is ex¬tremely well-exposed in the Uinta Basin of northeastern Utah, revealing a robust stratigraphic framework to document broad-scale fluvial-lacustrine facies architectures and associated trace fossil assemblages. Greenish- and gray-colored mudstone beds with interbedded tabular sandstone representing lacustrine environments contain the trace fossils Arenicolites and Gordia (= Haplotichnus). In contrast, red mudstone beds with interbedded channelized sandstone representing upstream fluvial and alluvial environments contain a variety of insect trace fossils, including Scoyenia, Ancorichnus, and nest structures. Transitional, interfingering lithologies of wetland or shallow, short-lived lacustrine environments on the alluvial plain contain the trace fossil Steinichnus. Although there are many small-scale (bed-scale) physical sedimen¬tary structures and trace fossils from continental subenvironments, this study focuses on the large-scale (member-scale) change in trace fossil assemblages, with results indicating that the ichnofacies corroborate continental sequence stratigraphic interpretations in a fluvial-lacustrine setting.
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Thuy, Ben, and Lea D. Numberger-Thuy. "The Northernmost Occurrence of the Tropical-Subtropical Brittle Star Ophiocoma (Echinodermata, Ophiuroidea) from a Late Cretaceous Rocky Shore in Southern Sweden." Taxonomy 3, no. 3 (June 25, 2023): 346–55. http://dx.doi.org/10.3390/taxonomy3030020.
Full textAbstract:
In spite of considerable progress during the last few years, the fossil record of the ophiuroids, or brittle stars, is still poorly known, especially with respect to taxa restricted to specific environments. Here, we describe new ophiuroid fossils collected from an Upper Cretaceous rocky shore in Ivö Klack, southern Sweden, consisting of fully disarticulated skeletal remains retrieved from the sediments deposited between boulders and hummocks. The fossils are identified as a new species of the extant ophiocomid genus Ophiocoma. In a critical revision of the ophiocomid fossil record, we show that all fossils previously assigned to the Ophiocomidae belong to other families. Thus, the fossil record of the Ophiocomidae is currently restricted to the new species described herein, and Amphiura? gigantiformis from the Miocene of Austria which, in fact, is a species of Ophiocoma. Since recent species of Ophiocoma exclusively occur in tropical to subtropical shallow subtidal environments, our discovery of a fossil Ophiocoma species in the rocky shore sediments of Ivö therefore conforms with the previously assumed subtropical palaeotemperatures prevailing in southern Sweden during the Late Cretaceous. Most notably, it represents the northernmost occurrence of an ophiocomid recorded to date.
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Droser, Mary L., Lidya G. Tarhan, Scott D. Evans, Rachel L. Surprenant, and James G. Gehling. "Biostratinomy of the Ediacara Member (Rawnsley Quartzite, South Australia): implications for depositional environments, ecology and biology of Ediacara organisms." Interface Focus 10, no. 4 (June 12, 2020): 20190100. http://dx.doi.org/10.1098/rsfs.2019.0100.
Full textAbstract:
The Precambrian Ediacara Biota—Earth's earliest fossil record of communities of macroscopic, multicellular organisms—provides critical insights into the emergence of complex life on our planet. Excavation and reconstruction of nearly 300 m 2 of fossiliferous bedding planes in the Ediacara Member of the Rawnsley Quartzite, at the National Heritage Ediacara fossil site Nilpena in South Australia, have permitted detailed study of the sedimentology, taphonomy and palaeoecology of Ediacara fossil assemblages. Characterization of Ediacara macrofossils and textured organic surfaces at the scale of facies, bedding planes and individual specimens has yielded unprecedented insight into the manner in which the palaeoenvironmental settings inhabited by Ediacara communities—particularly hydrodynamic conditions—influenced the aut- and synecology of Ediacara organisms, as well as the morphology and assemblage composition of Ediacara fossils. Here, we describe the manner in which environmental processes mediated the development of taphofacies hosting Ediacara fossil assemblages. Using two of the most common Ediacara Member fossils, Arborea and Dickinsonia , as examples, we delineate criteria that can be used to distinguish between ecological, environmental and biostratinomic signals and reconstruct how interactions between these processes have distinctively shaped the Ediacara fossil record.
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Leavitt, P. R., B. J. Hann, J. P. Smol, B. A. Zeeb, C. E. Christie, B. Wolfe, and H. J. Kling. "Paleolimnological analysis of whole-lake experiments: an overview of results from Experimental Lakes Area Lake 227." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 10 (October 1, 1994): 2322–32. http://dx.doi.org/10.1139/f94-235.
Full textAbstract:
High resolution analysis of laminated sediments from experimentally fertilized Lake 227 was used to compare sediment geochemistry and fossil abundance (siliceous algae, pigments, cladoceran remains) with 20 yr (1969–1989) of continuous historical records. Members of all fossil groups were correlated to the biomass of their respective producer populations (r = 0.52–0.66, P < 0.05, n = 20). Correlations were greatest when fossil abundance was expressed per unit organic matter and least when calculated as the accumulation rate. Comparison of groups showed that fossils of soft-bodied zooplankton (copepods, rotifers) and pigments from dinoflagellates were completely unreliable. The most informative fossils were chitinous remains of zooplankton (e.g., Bosmina), remains of siliceous algae, and pigments from chlorophytes and cyanobacteria. Ecosystem-level paleolimnology showed that fertilization was the most significant eutrophication event in the last 400 yr and that it impacted both pelagic and littoral communities. However, fossil zooplankton and pigment analyses indicated that food-web interactions (zooplanktivory, herbivory) also regulated plankton abundance and composition. Additionally, fossil analyses showed that some natural eutrophication occurred prior to 1969 and that plankton communities have continued to vary since 1975, despite constant rates of fertilization with nitrogen and phosphorus.
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Sun, Jiarui, Xiaokang Liu, Yunfei Huang, Fengyu Wang, Yongfang Sun, Jing Chen, Daoliang Chu, and Haijun Song. "Automatic identification and morphological comparison of bivalve and brachiopod fossils based on deep learning." PeerJ 11 (October 11, 2023): e16200. http://dx.doi.org/10.7717/peerj.16200.
Full textAbstract:
Fossil identification is an essential and fundamental task for conducting palaeontological research. Because the manual identification of fossils requires extensive experience and is time-consuming, automatic identification methods are proposed. However, these studies are limited to a few or dozens of species, which is hardly adequate for the needs of research. This study enabled the automatic identification of hundreds of species based on a newly established fossil dataset. An available “bivalve and brachiopod fossil image dataset” (BBFID, containing >16,000 “image-label” data pairs, taxonomic determination completed) was created. The bivalves and brachiopods contained in BBFID are closely related in morphology, ecology and evolution that have long attracted the interest of researchers. We achieved >80% identification accuracy at 22 genera and ∼64% accuracy at 343 species using EfficientNetV2s architecture. The intermediate output of the model was extracted and downscaled to obtain the morphological feature space of fossils using t-distributed stochastic neighbor embedding (t-SNE). We found a distinctive boundary between the morphological feature points of bivalves and brachiopods in fossil morphological feature distribution maps. This study provides a possible method for studying the morphological evolution of fossil clades using computer vision in the future.