Relevant bibliographies by topics / Early tetrapods

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  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Early tetrapods'

Author: Grafiati
Published: 4 June 2021
Last updated: 6 February 2022

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Journal articles on the topic "Early tetrapods"

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Witzmann, Florian. "Phylogenetic patterns of character evolution in the hyobranchial apparatus of early tetrapods." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 104, no. 2 (2013): 145–67. http://dx.doi.org/10.1017/s1755691013000480.

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ABSTRACTThe morphologies of the hyobranchial apparatus in early tetrapods are reviewed, based primarily on first-hand examination and supplemented by published descriptions. The basic arrangement of the “aquatic” hyobranchium, with four pairs of branchial arches and internal gills, was conserved to a remarkable degree across the fish–to–tetrapod transition and was retained in further evolution in adults of several tetrapod lineages. Thus, a fish-like hyobranchium in basal tetrapods does not necessarily represent a larval or paedomorphic character, respectively, as was often suggested in analogy to extant salamanders. Rather, it represents the plesiomorphic state of the adult hyobranchium in tetrapods. The changes in the hyobranchium during the fish–to–tetrapod transition include the reduction of the number of skeletal elements and their morphological simplification. In all three presently discussed scenarios of lissamphibian origin, the temnospondyl, lepospondyl and diphyly hypotheses, the internal gills were reduced independently within temnospondyls and on the amniote stem below seymouriamorphs. Evidence of remodelling into a true “terrestrial” hyobranchium, with reduction of the posterior branchial arches and modification to support terrestrial tongue feeding, is scarce in early tetrapods. It evolved within temnospondyls in zatracheids, amphibamids and lissamphibians, as well as once or several times in early amniotes or in their immediate stem-forms.
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Sallan, Lauren Cole. "Tetrapod-like axial regionalization in an early ray-finned fish." Proceedings of the Royal Society B: Biological Sciences 279, no. 1741 (2012): 3264–71. http://dx.doi.org/10.1098/rspb.2012.0784.

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Tetrapods possess up to five morphologically distinct vertebral series: cervical, thoracic, lumbar, sacral and caudal. The evolution of axial regionalization has been linked to derived Hox expression patterns during development and the demands of weight-bearing and walking on land. These evolutionary and functional explanations are supported by an absence of similar traits in fishes, living and extinct. Here, I show that, Tarrasius problematicus , a marine ray-finned fish from the Mississippian (Early Carboniferous; 359–318 Ma) of Scotland, is the first non-tetrapod known to possess tetrapod-like axial regionalization. Tarrasius exhibits five vertebral regions, including a seven-vertebrae ‘cervical’ series and a reinforced ‘sacrum’ over the pelvic area. Most vertebrae possess processes for intervertebral contact similar to tetrapod zygapophyses. The fully aquatic Tarrasius evolved these morphologies alongside other traits convergent with early tetrapods, including a naked trunk, and a single median continuous fin. Regional modifications in Tarrasius probably facilitated pelagic swimming , rather than a terrestrial lifestyle or walking gait, presenting an alternative scenario for the evolution of such traits in tetrapods. Axial regionalization in Tarrasius could indicate tetrapod-like Hox expression patterns, possibly representing the primitive state for jawed vertebrates. Alternately, it could signal a weaker relationship, or even a complete disconnect, between Hox expression domains and vertebrate axial plans.
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Daeschler, Edward B. "Early tetrapod jaws from the Late Devonian of Pennsylvania, USA." Journal of Paleontology 74, no. 2 (2000): 301–8. http://dx.doi.org/10.1017/s0022336000031504.

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Recent paleontological fieldwork in the Upper Devonian Catskill Formation at Red Hill in Clinton County, Pennsylvania, USA, has produced a diverse assemblage of vertebrate fossils including early tetrapods. The tetrapod Hynerpeton bassetti was described from the site in 1994 and a recently recognized partial lower jaw of that taxon is described here. Additionally, this paper describes a new Late Devonian tetrapod, Densignathus rowei new genus and species, based on a well-preserved lower jaw. This new taxon is characterized by dramatic widening of the jaw anterior of the adductor fossa, a pronounced twist in the orientation of ventral margin of the jaw, an uninterrupted exposure of Meckelian bone on the mesial surface, and weakly-developed radiating ornament on the lateral surface of the infradentaries. Although phylogenetic resolution within stem tetrapods is lacking, Densignathus rowei, n. gen. and sp., informs several topics including the sequence of character acquisition in the lower jaw, morphological diversity, and paleoecology of the earliest tetrapods.
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Clack, Jennifer A., Marcello Ruta, Andrew R. Milner, John E. A. Marshall, Timothy R. Smithson, and Keturah Z. Smithson. "Acherontiscus caledoniae : the earliest heterodont and durophagous tetrapod." Royal Society Open Science 6, no. 5 (2019): 182087. http://dx.doi.org/10.1098/rsos.182087.

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The enigmatic tetrapod Acherontiscus caledoniae from the Pendleian stage of the Early Carboniferous shows heterodontous and durophagous teeth, representing the earliest known examples of significant adaptations in tetrapod dental morphology. Tetrapods of the Late Devonian and Early Carboniferous (Mississippian), now known in some depth, are generally conservative in their dentition and body morphologies. Their teeth are simple and uniform, being cone-like and sometimes recurved at the tip. Modifications such as keels occur for the first time in Early Carboniferous Tournaisian tetrapods. Acherontiscus , dated as from the Pendleian stage, is notable for being very small with a skull length of about 15 mm, having an elongate vertebral column and being limbless. Cladistic analysis places it close to the Early Carboniferous adelospondyls, aïstopods and colosteids and supports the hypothesis of ‘lepospondyl’ polyphyly. Heterodonty is associated with a varied diet in tetrapods, while durophagy suggests a diet that includes hard tissue such as chitin or shells. The mid-Carboniferous saw a significant increase in morphological innovation among tetrapods, with an expanded diversity of body forms, skull shapes and dentitions appearing for the first time.
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Shubin, Neil H., and Hans-Dieter Sues. "Biogeography of early Mesozoic continental tetrapods: patterns and implications." Paleobiology 17, no. 3 (1991): 214–30. http://dx.doi.org/10.1017/s0094837300010575.

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The stratigraphic framework for Triassic and Early Jurassic continental strata has greatly changed in recent years. These revised correlations necessitate a review of traditional views of early Mesozoic continental faunal succession and biogeography. We have examined the relationship between tetrapod distribution and paleogeographic context during the Triassic and Early Jurassic on the basis of a data base comprising updated faunal lists for major early Mesozoic assemblages of continental tetrapods. Analysis of these data supports the hypothesis that there were few barriers to biotic interchange among continental tetrapods throughout the Triassic and Early Jurassic. Early Mesozoic tetrapod assemblages are dominated by widely distributed, often cosmopolitan families. Late Triassic patterns of latitudinal variation among tetrapod assemblages appear to be correlated to those seen among terrestrial plants and contrast with the extremely uniform distribution of Early Jurassic continental biotas.
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Godfrey, Stephen J., and Robert B. Holmes. "A tetrapod lower jaw from the Pennsylvanian (Westphalian A) of Nova Scotia." Canadian Journal of Earth Sciences 26, no. 5 (1989): 1036–40. http://dx.doi.org/10.1139/e89-084.

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The left half of a tetrapod lower jaw, from the Parrsboro Formation (Pennsylvanian, Westphalian A) of Nova Scotia, is preserved as a natural mold in a sandstone. Most of the features of this lower mandible are primitive for tetrapods or non-ichthyostegalian tetrapods. Although the presence of an adsymphysial tooth plate in this specimen is regarded as the retention of an osteolepiform feature, the tusk and replacement pit on this dermal bone may be unique to this taxon. The poor preservation of the lower jaws associated with some previously described Paleozoic tetrapods, together with the unique features in other early tetrapod jaws, precludes the reference of this mandible to any known tetrapod taxon.
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Friedman, Matt, and Martin D. Brazeau. "Sequences, stratigraphy and scenarios: what can we say about the fossil record of the earliest tetrapods?" Proceedings of the Royal Society B: Biological Sciences 278, no. 1704 (2010): 432–39. http://dx.doi.org/10.1098/rspb.2010.1321.

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Past research on the emergence of digit-bearing tetrapods has led to the widely accepted premise that this important evolutionary event occurred during the Late Devonian. The discovery of convincing digit-bearing tetrapod trackways of early Middle Devonian age in Poland has upset this orthodoxy, indicating that current scenarios which link the timing of the origin of digited tetrapods to specific events in Earth history are likely to be in error. Inspired by this find, we examine the fossil record of early digit-bearing tetrapods and their closest fish-like relatives from a statistical standpoint. We find that the Polish trackways force a substantial reconsideration of the nature of the early tetrapod record when only body fossils are considered. However, the effect is less drastic (and often not statistically significant) when other reliably dated trackways that were previously considered anachronistic are taken into account. Using two approaches, we find that 95 per cent credible and confidence intervals for the origin of digit-bearing tetrapods extend into the Early Devonian and beyond, spanning late Emsian to mid Ludlow. For biologically realistic diversity models, estimated genus-level preservation rates for Devonian digited tetrapods and their relatives range from 0.025 to 0.073 per lineage-million years, an order of magnitude lower than species-level rates for groups typically considered to have dense records. Available fossils of early digited tetrapods and their immediate relatives are adequate for documenting large-scale patterns of character acquisition associated with the origin of terrestriality, but low preservation rates coupled with clear geographical and stratigraphic sampling biases caution against building scenarios for the origin of digits and terrestrialization tied to the provenance of particular specimens or faunas.
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Lennie, Kendra I., Sarah L. Manske, Chris F. Mansky, and Jason S. Anderson. "Locomotory behaviour of early tetrapods from Blue Beach, Nova Scotia, revealed by novel microanatomical analysis." Royal Society Open Science 8, no. 5 (2021): 210281. http://dx.doi.org/10.1098/rsos.210281.

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Evidence for terrestriality in early tetrapods is fundamentally contradictory. Fossil trackways attributed to early terrestrial tetrapods long predate the first body fossils from the Late Devonian. However, the Devonian body fossils demonstrate an obligatorily aquatic lifestyle. Complicating our understanding of the transition from water to land is a pronounced gap in the fossil record between the aquatic Devonian taxa and presumably terrestrial tetrapods from the later Early Carboniferous. Recent work suggests that an obligatorily aquatic habit persists much higher in the tetrapod tree than previously recognized. Here, we present independent microanatomical data of locomotor capability from the earliest Carboniferous of Blue Beach, Nova Scotia. The site preserves limb bones from taxa representative of Late Devonian to mid-Carboniferous faunas as well as a rich trackway record. Given that bone remodels in response to functional stresses including gravity and ground reaction forces, we analysed both the midshaft compactness profiles and trabecular anisotropy, the latter using a new whole bone approach. Our findings suggest that early tetrapods retained an aquatic lifestyle despite varied limb morphologies, prior to their emergence onto land. These results suggest that trackways attributed to early tetrapods be closely scrutinized for additional information regarding their creation conditions, and demand an expansion of sampling to better identify the first terrestrial tetrapods.
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Hunt, Adrian P., and Spencer G. Lucas. "Tetrapod extinctions during the Late Triassic: evidence from the western United States." Paleontological Society Special Publications 6 (1992): 142. http://dx.doi.org/10.1017/s2475262200007024.

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Most recent workers have identified a major extinction of nonmarine tetrapods during the Late Triassic at the Carnian-Norian boundary. However, this identification is based principally on the stratigraphic distribution of tetrapods where there either is a major facies change at the Carnian-Norian boundary (Germany) or a significant unconformity that spans much of the early Norian (Argentina). Instead, we have examined the stratigraphic record of tetrapods in the western United States (Chinle Group) where there is a relatively continuous, nonmarine depositional and fossil record across the Carnian-Norian boundary that does not encompass major facies changes. The Chinle Group, because of its great area of exposure, more than one century of extensive collection and relatively complete publication, contains the world's best record of tetrapods across the Carnian-Norian boundary.The tetrapod record from the Chinle Group does not record a significant tetrapod extinction at the Carnian-Norian boundary. Instead, it documents a staggered extinction of some taxa during the late Carnian and the persistence of most taxa across the Carnian-Norian boundary. Thus, rhynchosaurs become extinct at the end of the early-late Carnian, whereas dicynodonts become extinct somewhat later, during the latest Carnian. Among metoposaurids, only the large taxa (Buettneria) disappear at the end of the Carnian. Other groups - phytosaurs, aetosaurs, rauisuchians, trilophosaurs, etc. - only exhibit some generic turnover at the Carnian-Norian boundary. The first appearance of dinosaurs, linked by some to a Carnian-Norian tetrapod extinction, is well in advance of the end of the Carnian. Thus, we conclude that the highest resolution tetrapod record of the late Carnian and early Norian does not document a significant tetrapod extinction at the end of the Carnian.
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Warren, Anne, and Susan Turner. "Tooth histology patterns in early tetrapods and the presence of ‘dark dentine’." Transactions of the Royal Society of Edinburgh: Earth Sciences 96, no. 2 (2005): 113–30. http://dx.doi.org/10.1017/s0263593300001267.

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ABSTRACTThe presence of a petaloid pattern (previously known as ‘dark dentine’) in cross sections of teeth of the embolomere Pholiderpeton attheyi has been used as a synapomorphy of the embolomeres or of the embolomeres plus the stem tetrapod, Crassigyrinus scoticus. Among the taxa studied, dentine that appears dark results from closely packed dentine tubules and can be found in any part of a tooth section in which such crowding occurs. The petaloid pattern is restricted to tooth sections of a particular diameter, and is obliterated in larger sections of teeth that show complex folding. Petaloid dentine has been found in all tetrapod teeth with plicidentine that were sectioned in this study, whether from stem tetrapods, the Embolomeri, Temnospondyli, or Stereospondyli, and has been recognised in some sarcopterygian fish, an extant actinopterygian fish, ichthyosaurs, and Varanus. The presence of petaloid dentine is neither a synapomorphy of the tetrapod node nor of any node within tetrapods
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Dissertations / Theses on the topic "Early tetrapods"

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Witzmann, Florian [Verfasser], Jörg [Akademischer Betreuer] Fröbisch, Michel [Akademischer Betreuer] Laurin, and Robert [Akademischer Betreuer] Reisz. "Physiological aspects of the fish-to-tetrapod transition : skin structure, breathing and feeding in early tetrapods / Florian Witzmann. Gutachter: Jörg Fröbisch ; Michel Laurin ; Robert Reisz." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2015. http://d-nb.info/1072008963/34.

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Pawley, Kat, and kat pawley@rmit edu au. "The Postcranial Skeleton of Temnospondyls (Tetrapoda: Temnospondyli)." La Trobe University. Department of Zoology, School of Life Sciences, 2006. http://www.lib.latrobe.edu.au./thesis/public/adt-LTU20061124.124055.

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Temnospondyls are large extinct fossil tetrapods; superficially resembling crocodiles in their general size, appearance and lifestyle. Temnospondyls are a group of early tetrapods, the oldest fossils are more than 340 million years old, and they existed for more than 200 million years. This doctoral thesis examined the postcranial skeleton of temnospondyls and its evolutionary history and diversification. Standard taxonomic techniques were used to distinguish between the types of variation observed in the postcranial skeleton and for phylogenetic analysis. The thesis consists of a series of published articles, three describing the postcranial skeletons of various temnospondyls, and three summary articles, all with extensive illustrations. To provide data, the postcranial skeletons of three temnospondyl taxa were described. The articulated postcranial skeleton of a basal stereospondyl (rhinesuchid) is immature, and paedomorphism of the postcranial skeleton in stereospondyls is discussed. The robust appendicular skeleton of Eryops megacephalus is plesiomorphic, well-ossified, and terrestrially adapted. The paedomorphic postcranial skeleton of Trimerorhachis insignis is plesiomorphic, and secondarily aquatic, the description includes growth stages. This study found that extensive morphogenetic variation is present in the postcranial skeleton of temnospondyls. Many phylogenetically significant characteristics develop with morphogenesis, they may be absent in early growth stages, and may never develop even in the largest growth stages of taxa with paedomorphic postcranial skeletons. Consequently, assessment of the presence or absence of a phylogenetically significant characteristic in any taxon may be dependant on the morphogenetic stage of the specimen examined. This finding has major implications for the phylogenetic analysis of temnospondyls and other early tetrapods. An overview of phylogenetic variation in the postcranial skeleton is presented, including a large phylogenetic analysis of the Temnospondyli. The most primitive temnospondyls possess fully ossified postcranial skeletons, well adapted for terrestrial locomotion, but some of the derived clades of temnospondyls have paedomorphic postcranial skeletons and are exclusively aquatic. For the first time, the postcranial skeleton of temnospondyls is comprehensively compared with that of other early tetrapods in the largest phylogenetic analysis to date, resulting in the unexpected discovery that temnospondyls are most closely related to the ancestors of amniotes. The Temnospondyli plus Neospondyli (Seymouriamorpha plus Cotylosauria plus Lepospondyli) forms a large new clade, the Terrapoda, defined by the presence of many derived synapomorphies. Some of the cranial synapomorphies of the Terrapoda are most likely related to improvements in hearing. The postcranial synapomorphies indicate that the Terrapoda are the first vertebrates to have evolved limbs that are well adapted for terrestrial locomotion. The Terrapoda are the first truly terrestrial vertebrates, their postcranial adaptations facilitated their colonisation of the land and consequent phylogenetic radiation during the early Carboniferous. Both analyses incorporate characters from previous analyses and many new postcranial characters. The results of the phylogenetic analyses are statistically more parsimonious than previous analyses and have much lower levels of homoplasy. Comparative analyses indicate that the distinctive results are most likely due to the increased use of characters pertaining to temnospondyls, increased use of postcranial characters, and differentiation between sources of morphological variation to minimise morphogenetic and phenotypic variation and elucidate true phylogenetic signal.
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Robinson, Jamie. "The evolution of the early tetrapod middle ear and associated structures." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1445909/.

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This thesis utilises modern techniques to investigate the origin and evolution of hearing in tetrapods with particular emphasis on the evolution of the middle ear region of early tetrapods and the proposed relatives of lissamphibians. Recent advances in computed tomography (CT) scanning and 3D computer reconstruction has allowed the re-examination of many important specimens in the early tetrapod fossil record. The combination of CT scanning and 3D reconstruction has permitted the detailed visualisation of many aspects of these fossil specimens that could not have been easily achieved by traditional means. These modern techniques have been used to model the middle ear region in a range of early tetrapods. This was undertaken to investigate the form of the middle ear region in stem group tetrapods and temnospondyls, a group frequently cited in the origin of lissamphibians. The high resolution models created by the modem techniques have been utilised to investigate the function of the middle ear region in early tetrapods. Additionally, fossil evidence for the origin of the varied middle ear structures observed in the extant lissamphibians has been elucidated from the new models. Furthermore, these models allow the quantitative measurements of many aspects of the middle ear. The analysis of the new models has demonstrated that the support function for the stapes in early tetrapods has been overstated. A crude but transitional hearing function for the stapes is proposed for a range of stem group tetrapods. It is shown that temnospondyls, which are thought to possess tympanic membranes also appear to have possessed numerous specialisations of the middle ear present in extant lissamphibians.
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Molnar, Julia Louise. "The biomechanics of vertebrae over evolutionary transitions between water and land: examples from early Tetrapoda and Crocodylomorpha." Thesis, Royal Veterinary College (University of London), 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618323.

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With the transition from water to land in early tetrapods, and with transitions to secondarily aquatic habits in numerous tetrapod lineages, the functions of the vertebral column were transformed. Morphological changes in the vertebral column are a major mechanism by which vertebrates accommodate changes in locomotor forces. Although morphometric measurements from vertebrae have been correlated with axial mechanics and locomotor behaviour in numerous extant taxa, few studies have sought to test or apply these principles in non-mammalian tetrapods. In my thesis, I reconstructed the vertebral mechanics of fossil taxa that represent intermediate stages in water/land transitions of their lineages. Study taxa were the basal tetrapod Pederpes finneyae, which is one of the earliest known tetrapods to show indications of terrestrial adaptation, and three extinct crocodylomorphs, Terrestrisuchus, Protosuchus, and Pelagosaurus, which span the spectrum from fully terrestrial to primarily aquatic. I used a combination of morphometric measurements and 3D virtual models of bone morphology to estimate intervertebral joint stiffness and range of motion. For comparison, I also reconstructed the vertebral mechanics of four related extant taxa. Correlations between vertebral morphometrics and axial stiffness were statistically tested in (cadaveric) modem crocodylians, and I validated my methodology by comparing my results with data from extant taxa. My results reveal similarities and differences between the two lineages. Intervertebral joint compliance and range of motion tended to decrease with adaptation for terrestrial locomotion, as expected, but this trend seems to have reversed in later forms. Additionally, vertebral mechanics may have been largely controlled by different structural mechanisms in different lineages. The relationship between biomechanics of vertebrae and environment appears to be more complex than previously supposed. However, approaches that combine experimental measurements from extant animals, thorough analysis of fossil morphology, and explicit phylogenetic considerations have the potential to greatly improve locomotor reconstructions of extinct taxa.
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Krummeck, William Desmond. "Ichnology and sedimentology of large tetrapod burrows in the latest Early Triassic Katberg Formation, south-eastern main Karoo Basin, South Africa." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/14233.

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Trace fossils in the form of large (~11 cm diameter and up to 2 m in length) burrows were studied at three localities in the Early Triassic Katberg Formation in the south-eastern and central parts of the main Karoo Basin, Eastern Cape, South Africa. The most interesting site, Hobbs Hill, northwest of Cathcart (Eastern Cape) has numerous burrows, contains an exceptionally well exposed sedimentary succession and bone beds. This site is also the type locality for the holotype of the parareptile Kitchingnathus untabeni (BP/1/1187). The aims of this dissertation are to: 1) reconstruct the local paleoenvironments of the burrow localities; 2) determine the purpose of the burrows; 3) identify the possible burrow makers based on the sedimentology and burrow morphology and 4) attempt to use photogrammetry and low-cost hardware to produce 3D digital burrows for improved descriptions. Insights into the survival strategies and behaviours of organisms during the P/T extinction recovery period are explored. Detailed analysis is mainly done on observations from the Hobbs Hill site; the results and interpretations are important for and compatible with the entire Katberg Formation. The interactions between the physical (sedimentary) and biological (animal behaviour) processes are important in ichnology and paleoenvironmental reconstruction. The analyses have therefore been undertaken through a multidisciplinary approach based on ichnological, sedimentological, petrographical, stratigraphic and paleontological evidence, gathered both in the field and laboratory.
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Olori, Jennifer Catherine. "The evolution of skeletal development in early tetrapods : anatomy and ontogeny of microsaurs (Lepospondyli)." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-05-3535.

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Because the ancestry of extant amphibians remains highly controversial, under traditional perspectives, amphibians and amniotes often are distinguished by differences in developmental mode rather than their evolutionary relationships. Resolution of relationships is important, however, because phylogeny affects interpretations of biology, including the evolution of development. To address those issues, I documented the growth and development of two extinct lepospondyls, Microbrachis pelikani and Hyloplesion longicostatum, and compared the patterns in those taxa to data from other tetrapods. I quantified allometry in the skeleton using both measurement-based and geometric morphometric analyses. I applied Ontogenetic Sequence Analysis (OSA), a size-independent method, to the reconstruction of ossification sequences based on fossils. I also documented skeletal morphogenesis and used Parsimov Analysis and Parsimov-based Genetic Inference of ossification sequence data to evaluate the three hypotheses of extant amphibian ancestry, the Lepospondyl (LH), Temnospondyl (TH), and Polyphyletic (PH) hypotheses. Skeletal growth in Microbrachis pelikani and Hyloplesion longicostatum is primarily isometric. Comparisons with data from other Paleozoic taxa suggest that isometry was the ancestral pattern of growth in tetrapods. All regression analyses had a linear fit indicating lack of an abrupt metamorphosis. Absence of metamorphosis is also supported by the possession of lateral lines in both taxa throughout ontogeny, and Microbrachis pelikani additionally retained gills. However, ossification of the skeleton was completed at small body size. The greatest resolution in ossification sequence reconstruction was achieved with OSA, but results from all reconstruction methods indicated advanced ossification of the pubis and delayed ossification of the scapula in the lepospondyls. In terms of total number of sequence shifts optimized across each hypothesis of amphibian relationships, the TH had the shortest tree length. However, the values for the three hypotheses did not differ significantly, demonstrating that none was supported strongly. Based on my synthesis of new developmental data, I propose that Microbrachis pelikani and Hyloplesion longicostatum expressed a mosaic pattern of skeletal development. That pattern included a gradual transition to an adult morphology, and a lack of an amphibian-like metamorphosis. A similar pattern is common to most early tetrapods and Eusthenopteron, supporting the hypothesis that metamorphosis is not ancestral for Tetrapoda.<br>text
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Lee-Thorp, Julia A., Ruiter D. De, B. Passey, and M. B. Sponheimer. "Isotopic Evidence for Dietary Variability in the Early Hominin Paranthropus robustus." 2006. http://hdl.handle.net/10454/4065.

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No<br>Traditional methods of dietary reconstruction do not allow the investigation of dietary variability within the lifetimes of individual hominins. However, laser ablation stable isotope analysis reveals that the ¿13C values of Paranthropus robustus individuals often changed seasonally and interannually. These data suggest that Paranthropus was not a dietary specialist and that by about 1.8 million years ago, savanna-based foods such as grasses or sedges or animals eating these foods made up an important but highly variable part of its diet.
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Books on the topic "Early tetrapods"

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Clack, Jennifer A. Gaining Ground: The Origin and Early Evolution of Tetrapods. Indiana University Press, 2002.

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C, Fraser Nicholas, and Sues Hans-Dieter 1956-, eds. In the shadow of the dinosaurs: Early Mesozoic tetrapods. Cambridge University Press, 1994.

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In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods. Cambridge University Press, 1995.

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(Editor), Nicholas C. Fraser, and Hans-Dieter Sues (Editor), eds. In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods. Cambridge University Press, 1997.

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Book chapters on the topic "Early tetrapods"

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Benton, Michael J. "The Early Tetrapods and Amphibians." In Vertebrate Palaeontology. Springer US, 1997. http://dx.doi.org/10.1007/978-1-4899-2865-8_4.

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Clack, Jennifer A., and Jason S. Anderson. "Early Tetrapods: Experimenting with Form and Function." In Evolution of the Vertebrate Ear. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-46661-3_4.

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Bolt, John R., and R. Eric Lombard. "Nature and Quality of the Fossil Evidence for Otic Evolution in Early Tetrapods." In The Evolutionary Biology of Hearing. Springer New York, 1992. http://dx.doi.org/10.1007/978-1-4612-2784-7_23.

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Clack, J. A. "The Stapes of Acanthostega gunnari and the Role of the Stapes in Early Tetrapods." In The Evolutionary Biology of Hearing. Springer New York, 1992. http://dx.doi.org/10.1007/978-1-4612-2784-7_24.

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Striedter, Georg F., and R. Glenn Northcutt. "The Invasion of Land." In Brains Through Time. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780195125689.003.0004.

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Basal stem tetrapods were fully aquatic but spent time at the water surface breathing air, which was useful at the end of the Devonian, when aquatic oxygen levels were low. After the Devonian, early tetrapods became fully terrestrial, at least as adults. This transition involved major changes in the musculoskeletal system for locomotion and the evolution of new modes of feeding. Aerial vision required changes in the eye but then allowed for high-resolution vision over long distances. In contrast, the lateral line systems are useless in air and were lost in fully terrestrial tetrapods. The brains of early tetrapods were relatively simple, possibly simplified through a process called paedomorphosis. The telencephalon’s main function in early tetrapods was to inhibit or disinhibit the lower brain regions. Later tetrapods diverged into extant amphibians and amniotes. Within the amphibian lineage, anurans evolved a tympanic ear, which increased their ability to hear airborne sounds.
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"11. The Early Radiation of Diapsid Reptiles." In Origins of the Higher Groups of Tetrapods. Cornell University Press, 2018. http://dx.doi.org/10.7591/9781501718335-013.

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"4. The Early Tetrapods: Classification and the Shapes of Cladograms." In Origins of the Higher Groups of Tetrapods. Cornell University Press, 2018. http://dx.doi.org/10.7591/9781501718335-006.

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Striedter, Georg F., and R. Glenn Northcutt. "The Origin of Jaws and Paired Fins." In Brains Through Time. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780195125689.003.0003.

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Between 450 and 500 million years ago, some vertebrates evolved paired fins and jaws, which made them more efficient swimmers and fiercer predators. These jawed vertebrates (i.e., gnathostomes) diversified in the Devonian period, but most died out during the end-Devonian mass extinction. The surviving gnathostomes had a more complex vestibular apparatus than their jawless ancestors, an expanded set of olfactory receptor genes, and vomeronasal receptors. A major innovation in the brains of gnathostomes was the emergence of a cerebellum that is distinct from the cerebellum-like areas found in all vertebrates. The telencephalon of early vertebrates processed primarily olfactory information, but this olfactory dominance was independently reduced in three later lineages, namely in cartilaginous fishes, ray-finned fishes, and tetrapods. In concert with the reduction in olfactory dominance, these lineages enlarged their telencephalon, relative to other brain regions, and evolved a telencephalic “dorsal pallium” that receives non-olfactory sensory information from the diencephalon.
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Cressler, Walter L. "Plant paleoecology of the Late Devonian Red Hill locality, north-central Pennsylvania, an Archaeopteris-dominated wetland plant community and early tetrapod site." In Wetlands through Time. Geological Society of America, 2006. http://dx.doi.org/10.1130/2006.2399(04).

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West-Eberhard, Mary Jane. "Heterotopy." In Developmental Plasticity and Evolution. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195122343.003.0020.

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Heterotopy is the spatial analogue of heterochrony: it is evolutionary change in the site of expression of a phenotypic trait. Gould (1977) attributes the word “heterotopy” to Haeckel, who used it in a more specialized way, to mean evolutionary change in the germ layer from which an organ differentiates. Wray and McClay (1989, p. 810) list several examples of heterotopy, including the origin of muscles in tetrapod forelimbs from different somites, the origin of vertebrate primordial germ cells from different germ layers, and homeotic “heterotopic” mutations that transfer appendages from one body segment to another. A broad definition of heterotopy extends the concept to include spatial patterning, not only transposition from one location to another, but spatial organization of quantitative processes such as growth (Zellditch et al., 1992) or the location of precursors during the development of homologous traits (Wray and McClay, 1988, p. 313). As in other categorizations of transitions, heterotopies could as well be classified in other ways, such as duplication. Severtzoff signaled a general relationship between heterochrony and heterotopy when he wrote that “heterochrony in development is a means of topographic coordination; i.e., new adaptation of the parts to each other.” Many morphological heterochronies in plants produce heterotopic change, since the morphological ontogeny of a plant is recorded in its adult architecture. Thus, changes in timing of expression of juvenile and adult leaf forms result in heterotopic change in architecture of the mature plant, with the juvenile leaves appearing high on the stem, rather than only basally as before. A clear and oft-described example of environmentally mediated heterotopic change was demonstrated in early experiments on melanization in the Himalayan rabbit (Sturtevant, 1913; Iljin, 1927; Iljin and Iljin, 1930; see discussions in Schmalhausen, 1949 [1986]; Huxley, 1942; Levinton, 1988). In the Himalayan rabbit, as in the Siamese cat, pigment normally develops only in the extremities, where skin temperature is below the general body temperature. Individuals raised at temperatures above 30°C develop white extremities.
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Conference papers on the topic "Early tetrapods"

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Lucas, Spencer G. "HOW COMPILED AND INCORRECT CORRELATIONS CAN “CREATE” A MASS EXTINCTION: THE CASE OF EARLY PERMIAN TETRAPODS." In GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-297115.

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Temple, David Porter, and Robert T. Bakker. "VEGGIE-SAUR DEBUT?:EARLIEST COPROLITE FROM HI-FIBER LARGE TETRAPOD, EARLY PERMIAN, SEYMOUR, TX." In GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-322320.

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