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Disarticulation and Preservation of Fossil Echinoderms: Recognition of Ecological-Time Information in the Echinoderm Fossil Record

2021-02-11 Reference
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Release : 2021-02-11
Genre : Reference
Kind : eBook
Book Rating : 472/5 ( reviews)

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Book Synopsis Disarticulation and Preservation of Fossil Echinoderms: Recognition of Ecological-Time Information in the Echinoderm Fossil Record by : William I. Ausich

Download or read book Disarticulation and Preservation of Fossil Echinoderms: Recognition of Ecological-Time Information in the Echinoderm Fossil Record written by William I. Ausich. This book was released on 2021-02-11. Available in PDF, EPUB and Kindle. Book excerpt: The history of life on earth is largely reconstructed from time-averaged accumulations of fossils. A glimpse at ecologic-time attributes and processes is relatively rare. However, the time-sensitive and predictability of echinoderm disarticulation makes them model organisms to determine post-mortem transportation and allows recognition of ecological-time data within paleocommunity accumulations. Unlike many other fossil groups, this has allowed research on many aspects of echinoderms and their paleocommunities, such as the distribution of soft tissues, assessment of the amount of fossil transportation prior to burial, determination of intraspecific variation, paleocommunity composition, estimation of relative abundance of taxa in paleocommunities, determination of attributes of niche differentiation, etc. Crinoids and echinoids have received the most amount of taphonomic research, and the patterns present in these two groups can be used to develop a more thorough understanding of all echinoderm clades.

A Review and Evaluation of Homology Hypotheses in Echinoderm Paleobiology

2023-04-13 Science
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Release : 2023-04-13
Genre : Science
Kind : eBook
Book Rating : 168/5 ( reviews)

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Book Synopsis A Review and Evaluation of Homology Hypotheses in Echinoderm Paleobiology by : Colin D. Sumrall

Download or read book A Review and Evaluation of Homology Hypotheses in Echinoderm Paleobiology written by Colin D. Sumrall. This book was released on 2023-04-13. Available in PDF, EPUB and Kindle. Book excerpt: The extraxial-axial theory (EAT) and universal elemental homology (UEH) are often portrayed as mutually exclusive hypotheses of homology within pentaradiate Echinodermata. EAT describes homology upon the echinoderm bauplan, interpreted through early post-metamorphic growth and growth zones, dividing it into axial regions generally associated with elements of the ambulacral system and extraxial regions that are not. UEH describes the detailed construction of the axial skeleton, dividing it into homologous plates and plate series based on symmetry, early growth, and function. These hypotheses are not in conflict; the latter is rooted in refinement of the former. Some interpretive differences arise because many of the morphologies described from eleutherozoan development are difficult to reconcile with Paleozoic forms. Conversely, many elements described for Paleozoic taxa by UEH, such as the peristomial border plates, are absent in eleutherozoans. This Element recommends these two hypotheses be used together to generate a better understanding of homology across Echinodermata.

A Review of Blastozoan Echinoderm Respiratory Structures

2022-12-31
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Release : 2022-12-31
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Kind : eBook
Book Rating : 609/5 ( reviews)

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Book Synopsis A Review of Blastozoan Echinoderm Respiratory Structures by : Sarah L. Sheffield

Download or read book A Review of Blastozoan Echinoderm Respiratory Structures written by Sarah L. Sheffield. This book was released on 2022-12-31. Available in PDF, EPUB and Kindle. Book excerpt: Echinoderms have evolved diverse and disparate morphologies throughout the Phanerozoic. Among them, blastozoans, an extinct group of echinoderms that were an important component of Paleozoic marine ecosystems, are primarily subdivided into groups based on the morphology of respiratory structures. However, systematic and phylogenetic research from the past few decades have shown that respiratory structures in blastozoans are not group-defining and they have re-evolved throughout echinoderm evolution. This Element provides a review of the research involving blastozoan respiratory structures, along with research concerning the morphology, paleoecology, and ontogeny of each of the major groupings of blastozoans as it relates to their corresponding respiratory structures. Areas of future research in these groups are also highlighted.

Follow the Fossils

2021-12-09 Science
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Release : 2021-12-09
Genre : Science
Kind : eBook
Book Rating : 958/5 ( reviews)

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Book Synopsis Follow the Fossils by : Samantha B. Ocon

Download or read book Follow the Fossils written by Samantha B. Ocon. This book was released on 2021-12-09. Available in PDF, EPUB and Kindle. Book excerpt: The ability for people to connect, learn, and communicate about science has been enhanced through the Internet, specifically through social media platforms. Facebook and Twitter are well-studied, while Instagram is understudied. This Element provides insight into using Instagram as a science education platform by pioneering a set of calculated metrics, using a paleontology-focused account as a case study. Framed by the theory of affinity spaces, the authors conducted year-long analyses of 455 posts and 139 stories that were created as part of an informal science learning project. They found that team activity updates and posts outside of their other categories perform better than their defined categories. For Instagram stories, the data show that fewer slides per story hold viewers' attention longer, and stories using the poll tool garnered the most interaction. This Element provides a baseline to assess the success of Instagram content for science communicators and natural science institutions.

Niche Evolution and Phylogenetic Community Paleoecology of Late Ordovician Crinoids

2022-05-26 Reference
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Release : 2022-05-26
Genre : Reference
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Book Rating : 947/5 ( reviews)

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Book Synopsis Niche Evolution and Phylogenetic Community Paleoecology of Late Ordovician Crinoids by : Selina R. Cole

Download or read book Niche Evolution and Phylogenetic Community Paleoecology of Late Ordovician Crinoids written by Selina R. Cole. This book was released on 2022-05-26. Available in PDF, EPUB and Kindle. Book excerpt: Fossil crinoids are exceptionally suited to deep-time studies of community paleoecology and niche partitioning. By merging ecomorphological trait and phylogenetic data, this Element summarizes niche occupation and community paleoecology of crinoids from the Bromide fauna of Oklahoma (Sandbian, Upper Ordovician). Patterns of community structure and niche evolution are evaluated over a ~5 million-year period through comparison with the Brechin Lagerstätte (Katian, Upper Ordovician). The authors establish filtration fan density, food size selectivity, and body size as major axes defining niche differentiation, and niche occupation is strongly controlled by phylogeny. Ecological strategies were relatively static over the study interval at high taxonomic scales, but niche differentiation and specialization increased in most subclades. Changes in disparity and species richness indicate the transition between the early-middle Paleozoic Crinoid Evolutionary Faunas was already underway by the Katian due to ecological drivers and was not triggered by the Late Ordovician mass extinction.

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