2,963 research outputs found

    Judicial Scrutiny of Commercial Speech

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    In 1942, the Supreme Court held that commercial speech was not protected by the First Amendment. Since that time, the Court has adopted the doctrine that the state\u27s concern for the protection of the public is subordinate to the public\u27s right to know. Although the Court has not been unanimous on the issues, the Court has pretty much used the following test to determine whether a particular commercial expression is protected

    The judicial world of Ruth Bader Ginsburg.

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    The origin of turtles: A paleontological perspective

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    The origin of turtles and their unusual body plan has fascinated scientists for the last two centuries. Over the course of the last decades, a broad sample of molecular analyses have favored a sister group relationship of turtles with archosaurs, but recent studies reveal that this signal may be the result of systematic biases affecting molecular approaches, in particular sampling, non-randomly distributed rate heterogeneity among taxa, and the use of concatenated data sets. Morphological studies, by contrast, disfavor archosaurian relationships for turtles, but the proposed alternative topologies are poorly supported as well. The recently revived paleontological hypothesis that the Middle Permian Eunotosaurus africanus is an intermediate stem turtle is now robustly supported by numerous characters that were previously thought to be unique to turtles and that are now shown to have originated over the course of tens of millions of years unrelated to the origin of the turtle shell. Although E. africanus does not solve the placement of turtles within Amniota, it successfully extends the stem lineage of turtles to the Permian and helps resolve some questions associated with the origin of turtles, in particular the non-composite origin of the shell, the slow origin of the shell, and the terrestrial setting for the origin of turtles

    A review of the fossil record of turtles of the clade Pan-Chelydridae

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    Turtles of the total clade Pan-Chelydridae have a relatively sparse fossil record that reaches back to the Late Cretaceous (Santonian). The clade was only present in North America during the Cretaceous but spread along unclear routes to Asia and Europe during the Paleocene, only to go extinct on those continents by the end of the Pliocene. Final dispersal to South America took place at some time during the late Neogene. The ecology of stem chelydrids seems to have been similar to that of the extant Chelydra serpentina, although more primitive representatives were more molluscivorous as inferred from their broader triturating surfaces. Current phylogenies only recognize five internested clades: Pan-Chelydridae, Chelydridae, Chelydropsis, Chelydra and Macrochelys. A taxonomic review of the group concludes that of 31 named fossil taxa, 8 are nomina valida, 10 are nomina invalida, 9 are nomina dubia, 1 is a nomen nudum and 1 is a regular, unavailable name

    A review of the fossil record of basal mesozoic turtles

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    Turtles (Testudinata) are the clade of amniotes characterized by a complete turtle shell. New insights into the phylogeny of the group have revealed that a diverse assemblage of fossil turtles populate the stem lineage that lead to the turtle crown (Testudines). To aid communication, the terms Mesochelydia and Perichelydia are herein defined for two internested clades more inclusive than Testudines but less inclusive than Testudinata. The earliest representatives of Testudinata are found globally in Late Triassic (Norian) to Middle Jurassic deposits. In concert with the vicariant split of crown Testudines into three primary clades (i.e., Paracryptodira, Pan- Pleurodira, and Pan-Cryptodira), basal perichelydians diversify into three additional clades with overlapping geographic distributions: Helochelydridae in Euramerica, Sichuanchelyidae in Asia, and Meiolaniformes in southern Gondwana. Sedimentological, anatomical, and histological data universally hint at terrestrial habitat preference among the earliest stem turtles, but a more mixed, though unambiguously continental signal is apparent further towards the crown. A taxonomic review of Mesozoic stem turtles, excluding representatives of the Gondwanan Meiolaniformes, concludes that of 48 named taxa, 26 are nomina valida, 18 are nomina invalida, 4 are nomina dubia, 1 is a nomen nudum, and that 9 do not represent turtles

    A Review of the Fossil Record of Turtles of the Clades Platychelyidae and Dortokidae

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    The fossil record of platychelyid turtles expands from the Late Jurassic (Oxfordian) of Cuba to the Early Cretaceous (Valanginian) of Colombia. Platychelyids were adapted to freshwater to coastal environments. Current phylogenies confidently suggest that platychelyids are situated along the stem lineage of crown Pleurodira. A taxonomic review of the group concludes that of six named “platychelyid” taxa, four are valid and two are nomina nuda. Dortokids are a poorly understood group of freshwater aquatic turtles that are restricted to the Early Cretaceous (Barremian) to Eocene (Lutetian) of Europe. The phylogenetic position of the group is still under debate, but there is some evidence that these turtles are positioned along the stem lineage of crown Pleurodira as well. A taxonomic review of the group concludes that of four named dortokid taxa, two are valid, one is a nomen invalidum and one a nomen nudum

    A reassessment of the late jurassic turtle Eurysternum wagleri (Eucryptodira, Eurysternidae)

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    Eurysternum wagleri is one of the first named, yet most poorly understood turtles from the Late Jurassic of Europe. Over the years, many specimens have been referred to and many species synonymized with E. wagleri, but little consensus is apparent, and the taxonomy is therefore highly confusing. Based on the rare, only known illustration of the lost holotype and on the reassessment of select individuals, the species E. wagleri is recharacterized herein. Eurysternum wagleri is diagnosed by a deep pygal notch, a carapace with a pentagonal outline, a contribution of vertebral 5 to the posterior carapace margin, three cervical scales, very wide vertebral scales with a well-developed radiating pattern, well-developed costoperipheral fontanelles in medium-sized individuals, a plastron connected to the carapace by ligaments, gracile, peg-like bony projections of the hyo- and hypoplastra, and large, oval-to-quadrangular lateral plastral fontanelles. A lectotype is designated for Acichelys redenbacheri, and this taxon is interpreted as the junior subjective synonym of Eurysternum wagleri. All other, previously proposed synonymies are rejected, because they lack characters that would allow diagnosing them as E. wagleri
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