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1.
A series of cranial remains as well as a few postcranial elements attributed to the basal eusuchian Allodaposuchus precedens are described from Velaux‐La Bastide Neuve, a Late Cretaceous continental locality in southern France. Four skulls of different size represent an ontogenetic series and permit an evaluation of the morphological variability in this species. On this basis, recent proposals that different species of Allodaposuchus inhabited the European archipelago are questioned and A. precedens is recognized from other Late Cretaceous deposits of France and Romania. A dentary bone is described for the first time in A. precedens and provides a basis to reconsider the validity of two taxa, Ischyrochampsa meridionalis and Musturzabalsuchus buffetauti, which are interpreted as possible junior synonyms of Allodaposuchus. These results allow the diversity of Late Cretaceous eusuchians from Europe to be refined and recognize a basal stock known as the Hylaeochampsidae sharing an absence of external mandibular fenestrae. Within this family, Allodaposuchus occupies a basal position relative to Acynodon, Iharkutosuchus and Hylaeochampsa. © 2015 The Linnean Society of London  相似文献   

2.
Plesiadapids are extinct relatives of extant euarchontans (primates, dermopterans, and scandentians), which lived in North America and Europe during the Paleocene and Early Eocene. The only genus of plesiadapid whose species are absent from Paleocene strata is Platychoerops. Further, Platychoerops is the only group found in sediments post‐dating the Paleocene‐Eocene boundary (PEB) by a substantial period of time based on large samples. It is also substantially different from other plesiadapids in dental features thought to reflect ecology. Its evolution has been linked to the rapid global climate change and faunal turnover marking the PEB. Platychoerops and Plesiadapis tricuspidens have been reconstructed as members of a single lineage by some authors. We describe a specimen (right p3‐m3) that we attribute to a new species, Platychoeropsantiquus, from the unequivocally Paleocene (MP6) Mouras Quarry of Mont de Berru, France. It has strong morphological affinities to Platychoerops daubrei yet co‐occurs with many specimens of Plesiadapis tricuspidens, as well as the plesiadapid Chiromyoides campanicus. The existence of a species of Platychoerops prior to the PEB decouples the evolution of Platychoerops from the climate change and faunal turnover event associated with the PEB. Furthermore, the co‐occurrence of Platychoerops with P. tricuspidens refutes the idea of a single lineage for these taxa. Instead, Platychoerops may be more closely related to North American Plesiadapis cookei (a previous alternate hypothesis). We suggest character displacement in a Paleocene immigrant population of P. cookei resulting from competition with sympatric P. tricuspidens, as a likely scenario for the evolution of Platychoerops. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

3.
Two single assemblages of cereals and chaff from the oppidum Bibracte, (Burgundy, France), give evidence of cereal trade, food supply and crop processing in late Celtic and early Roman times. The first deposit consists mainly of Triticum dicoccon chaff which was buried in a wooden box near the sanctuary of La Terrasse. The second assemblage was a store of different wheats and barley excavated in a Roman cellar at the Pature du Couvent. The analyses of these finds are presented, and recent archaeobotanical research at Mont Beuvray is summarized.  相似文献   

4.
Hitherto unpublished crocodylian remains, including four skull fragments, from the lignite-bearing localities of Valdonne and Fuveau (Santonian–Campanian), south-eastern France, are described. They complement the original material of ' Crocodilus affuvelensis ' described by Matheron (1869) and Repelin (1930). Based on overlapping specimens, available elements of the rostrum, the palate, the skull table, the mandible and the pterygoid can be shown to belong to a single taxon, for which a reconstruction is proposed. Designation of a neotype has been proposed to the ICZN committee. A new genus, Massaliasuchus , is proposed here to designate the crocodylian originally described as Crocodilus affuvelensis . This crocodylian presents affinities with basal alligatoroids and complements the picture of crocodylian diversity during the Late Cretaceous in the European archipelago. Massaliasuchus affuvelensis is compared with other European taxa and with basal alligatoroids from North America. The putative basal position of Massaliasuchus as well as its early geological age suggest that the geographical origin of the Alligatoroidea is still uncertain.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 567–580.  相似文献   

5.
The Synurophyceae is a well-supported clade of ecologically important heterokont algae found largely in freshwater planktonic habitats worldwide, whose members have cell coverings consisting of species-specific siliceous scales overlapped in a highly organized manner. Many synurophytes have been described as endemic and are found only in specific regions of the world. A thriving population of the European endemic, Mallomonas intermedia, was discovered in a remote desert pond situated in the Virgin Valley, Nevada, USA and in a stratigraphic sequence from the middle Eocene fossil locality known as Horsefly in British Columbia, Canada. Both North American finds were closely compared with populations from Europe, confirming the identifications. Before these discoveries, this species was recorded from numerous waterbodies exclusively in Europe, but was lacking from hundreds of sites examined from other continents. Its presence in western North America during the warm middle Eocene confirms that historically this species had a significantly wider distribution and may be best classified as a palaeoendemic. Additional species uncovered from a second fossil locality that are closely related to M. intermedia further support the presence of this lineage in North America during the Eocene. The living population in northern Nevada presents an enigma. Does this remote desert population represent a remnant population that has gone undetected until now, or is it a recent arrival from an unknown region by an unknown vector?  相似文献   

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There are several models in the literature for predicting enteric methane (CH4) emissions. These models were often developed on region or country‐specific data and may not be able to predict the emissions successfully in every region. The majority of extant models require dry matter intake (DMI) of individual animals, which is not routinely measured. The objectives of this study were to (i) evaluate performance of extant models in predicting enteric CH4 emissions from dairy cows in North America (NA), Europe (EU), and Australia and New Zealand (AUNZ) and (ii) explore the performance using estimated DMI. Forty extant models were challenged on 55, 105, and 52 enteric CH4 measurements (g per lactating cow per day) from NA, EU, and AUNZ, respectively. The models were ranked using root mean square prediction error as a percentage of the average observed value (RMSPE) and concordance correlation coefficient (CCC). A modified model of Nielsen et al. (Acta Agriculturae Scand Section A, 63 , 2013 and 126) using DMI, and dietary digestible neutral detergent fiber and fatty acid contents as predictor variables, were ranked highest in NA (RMSPE = 13.1% and CCC = 0.78). The gross energy intake‐based model of Yan et al. (Livestock Production Science, 64 , 2000 and 253) and the updated IPCC Tier 2 model were ranked highest in EU (RMSPE = 11.0% and CCC = 0.66) and AUNZ (RMSPE = 15.6% and CCC = 0.75), respectively. DMI of cows in NA and EU was estimated satisfactorily with body weight and fat‐corrected milk yield data (RMSPE < 12.0% and CCC > 0.60). Using estimated DMI, the Nielsen et al. (2013) (RMSPE = 12.7 and CCC = 0.79) and Yan et al. (2000) (RMSPE = 13.7 and CCC = 0.50) models still predicted emissions in respective regions well. Enteric CH4 emissions from dairy cows can be predicted successfully (i.e., RMSPE < 15%), if DMI can be estimated with reasonable accuracy (i.e., RMSPE < 10%).  相似文献   

8.
An abundant fossil record of the snake clade Scolecophidia exists in Europe; however, the minute snake is noticeably absent in reports about the North American Paleogene and Neogene. Presented here are four localities from Florida, USA, that contain scolecophidian remains older than the Pleistocene: Thomas Farm (late Early Miocene, Hemingfordian Land Mammal Age, LMA), Live Oak (Oligocene-Miocene transition, latest Arikareean LMA), White Springs 3B (late Arikareean LMA), and Brooksville 2 (Late Oligocene, middle Arikareean LMA). These remains extend their known existence by about 26 m.y. and are now the oldest reported scolecophidian remains in North America. Molecular evidence on extant scolecophidians concludes that these tiny snakes have a Gondwanan origin. Interestingly, the oldest record of a scolecophidian is from Europe (Belgium) and dates back to the middle Paleocene (MP 1–5). The earliest African record of the snake clade comes from the Paleocene-Eocene boundary in Morocco. The clade is apparently absent from Europe and Middle East deposits dating from the latest Eocene through to the latest Oligocene (MP 19–30) and to the Early Miocene (MN 4). A portion of this time is known as the booid ‘Dark Period’ which represents an apparent response to global aridization and cooling. Scolecophidians appear to re-emerge into the southern Eurasian record in the Early Miocene (MN 4) and become widely dispersed throughout Europe and Middle East. The fossil record of these minute snakes is largely absent in southern Asia and South America. It is possible that the current lack of a decent fossil scolecophidian record outside of Europe and Middle East is due mainly to a bias in the methodology to recover fossils; wet sieving sediments through < 1.0 mm mesh is needed to recover the minuscule vertebrae.  相似文献   

9.
Internal transcribed spacer (ITS nuclear rDNA) data have been obtained from 190 terrestrial orchid species, encompassing all genera and the great majority of the widely recognized species of Orchidinae, a heterogeneous selection of species of Habenariinae, and single species of Satyriinae and Disinae (the latter serving as outgroup). The resulting parsimony‐based phylogeny reveals 12 well‐resolved clades within the Orchidinae, based on Anacamptis s.l., Serapias, Ophrys, SteveniellaHimantoglossum s.l. (including ‘Comperia’ and ‘Barlia’, most species being 2n = 36), Neotinea s.l., TraunsteineraChamorchis, Orchis s.s., PseudorchisAmerorchisGalearisNeolindleyaPlatanthera s.l. (most 2n = 42), Dactylorhiza s.l., Gymnadenia s.l. (most 2n = 40, 80), Ponerorchis s.l.Hemipilia s.l.AmitostigmaNeottianthe, and Brachycorythis (most 2n = 42). Relationships are less clearly resolved among these 12 clades, as are those within Habenariinae; the subtribe appears either weakly supported as monophyletic or as paraphyletic under maximum parsimony, and the species‐rich genus Habenaria is clearly highly polyphyletic. The triphyly of Orchis as previously delimited is confirmed, and the improved sampling allows further generic transfers to Anacamptis s.l. and Neotinea s.l. In addition, justifications are given for: (1) establishing Steveniella as the basally divergent member of an appreciably expanded Himantoglossum that incorporates the former genera ‘Barlia’ and ‘Comperia’, (2) reuniting ‘Piperia’ with a broadly defined Platanthera as section Piperia, necessitating ten new combinations, (3) broadening Ponerorchis to include Chusua, and Hemipilia to include single ‘orphan’ species of Ponerorchis and Habenaria, and (4) recognizing ‘Gymnadeniacamtschatica as the monotypic Neolindleya camtschatica within the PseudorchisPlatanthera clade. Few further generic transfers are likely in Orchidinae s.s., but they are anticipated among habenariid genera, on acquisition of additional morphological and molecular evidence; one probable outcome is expansion of Herminium. Species‐level relationships are also satisfactorily resolved within most of the major clades of Orchidinae, with the notable exceptions of Serapias, the derived sections of Ophrys, Himantoglossum s.s., some sections within Dactylorhiza, the former genus ‘Nigritella’ (now tentatively placed within Gymnadenia s.l.), Hemipilia s.l., and possibly Ponerorchis s.s. Relationships among the 12 major clades broadly accord with bona fide records of intergeneric hybridization. Current evidence supports the recently recognized 2n = 36 clade; it also indicates a 2n = 40 clade that is further diagnosed by digitate root‐tubers, and is derived relative to the recently recognized clade of exclusively Asian genera (Ponerorchis s.l.Hemipilia s.l.AmitostigmaNeottianthe). This in turn appears derived relative to the Afro‐Asiatic Brachycorythis group; together, these two clades identify the plesiomorphic chromosome number as 2n = 42. If the African genus Stenogolottis is correctly placed as basally divergent within a monophyletic Habenariinae, the tribe Orchideae and subtribes Orchidinae and Habenariinae could all have originated in Africa, though in contrast the Asiatic focus of the basally divergent members of most major clades of Orchidinae suggests an Asiatic radiation of the subtribe. Morphological characters informally ‘mapped’ across the molecular phylogeny and showing appreciable levels of homoplasy include floral and vegetative pigmentation, flower shape, leaf posture, gynostemium features, and various pollinator attractants. Qualitative comparison of, and reciprocal illumination between, degrees of sequence and morphological divergence suggests a nested set of radiations of progressively decreasing phenotypic magnitude. Brief scenarios, both adaptive and non‐adaptive, are outlined for specific evolutionary transitions. Recommendations are made for further species sampling, concentrating on Asian Orchidinae (together with the Afro‐Asiatic Brachycorythis group) and both Asian and Southern Hemisphere Habenariinae, and adding plastid sequence data. Taxonomic changes listed are: Anacamptis robusta (T.Stephenson) R.M.Bateman, comb. nov. , A. fragrans (Pollini) R.M.Bateman, comb. nov. , A. picta (Loiseleur) R.M.Bateman, comb. nov. , Neotinea commutata (Todari) R.M.Bateman, comb. nov. , N. conica (Willdenow) R.M.Bateman, comb. nov. , Platanthera elegans Lindley ssp. maritima (Rydberg) R.M.Bateman, comb. nov. , P. elegans Lindley ssp. decurtata (R.Morgan & Glicenstein) R.M.Bateman, comb. nov. , P. elongata (Rydberg) R.M.Bateman, comb. nov. , P. michaelii (Greene) R.M.Bateman, comb. nov. , P. leptopetala (Rydberg) R.M.Bateman, comb. nov. , P. transversa (Suksdorf) R.M.Bateman, comb. nov. , P. cooperi (S.Watson) R.M.Bateman, comb. nov. , P. colemanii (R.Morgan & Glicenstein) R.M.Bateman, comb. nov. , P. candida (R.Morgan & Ackerman) R.M.Bateman, comb. nov. and P. yadonii (R.Morgan & Ackerman) R.M.Bateman, comb. nov. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142 , 1–40.  相似文献   

10.
The Sima de las Palomas, southeastern Spain, has yielded a series of Neandertal postcranial remains, including immature and mature isolated elements and the fragmentary partial skeleton of a young adult (Palomas 92). The remains largely conform to the general late archaic/Neandertal morphological pattern in terms of humeral diaphyseal shape, pectoralis major tuberosity size and pillar thickness, ulnar coronoid process height, manual middle phalangeal epiphyseal breadth, manual distal phalangeal tuberosity shape and breadth, femoral diaphyseal shape, and probably body proportions. Palomas 92 contrasts with the Neandertals in having variably gracile hand remains, a more sellar trapezial metacarpal 1 facet, more anteroposteriorly expanded mid-proximal femoral diaphysis, and less robust pedal proximal phalanges. The Palomas Neandertals contrast with more northern European Neandertals particularly in various reflections of overall body size.  相似文献   

11.
We describe crocodylian remains from the Early Miocene (MN4) site of Els Casots (Subirats, Vallès-Penedès Basin, NE of the Iberian Peninsula). Referral to Diplocynodon (Alligatoroidea: Diplocynodontidae) is justified by several cranial and postcranial features, including: (1) the subequal and confluent alveoli of the maxilla (fourth and fifth) and dentary (third and fourth); (2) the position of the foramen aëreum on the quadrate; (3) the small and ventrally reflected medial hemicondyle of the quadrate; (4) the distinct dorsoventral step on the frontal; and (5) the bipartite ventral osteoderms. Multiple morphological features are consistent with an attribution to Diplocynodon ratelii, previously known from the Early Miocene (MN2) of France, and discount an alternative attribution to other species of the genus, including Diplocynodon ungeri from the Middle Miocene (MN5) of Austria. The described material from Els Casots is smaller in size than the French material of D. ratelii, possibly reflecting an earlier ontogenetic stage. The described remains constitute the first report of D. ratelii and the youngest record of Diplocynodon in the Iberian Peninsula, where only Diplocynodon muelleri and Diplocynodon tormis have been previously reported. The presence of Diplocynodon further supports the lacustrine depositional environment previously inferred for Els Casots and also indicates a relatively high temperature.  相似文献   

12.
Metatherian petrosal bones were recovered from the early Late Palaeocene Itaboraí, Brazil, and are formally described. A cladistic analysis of the distribution of 56 petrosal and basicranial characters among extant and fossil metatherians was conducted, resulting in seven parsimonious trees. Relationships among metatherian ingroup taxa are congruent with current understanding of metatherian phylogeny. Metatheria is diagnosed by eight petrosal synapomorphies: stapedial artery absent in adults; reduced, intramural prootic canal; extrabullar internal carotid artery; inferior petrosal sinus between petrosal, basisphenoid, and basioccipital; cava supracochleare and epiptericum completely separated; reduction of the lateral flange; reduction of the anterior lamina; separation of the jugular foramen from the opening for the inferior petrosal sinus. The Palaeocene taxa Mayulestes , Pucadelphy s, and Andinodelphys from Tiupampa, and Petrosal Type II from Itaboraí are the sister groups of all other South American and Australian metatherians. This analysis confirms previous results showing the South American 'monito del monte' Dromiciops nested within the Australasian radiation. Within this australidelphian clade, Dromiciops is closely related to the dasyurids. The South American Caenolestes appears more closely related to the Australidelphia than to the South American didelphids. The Petrosal Types I, III, IV and V from Itaboraí are the stem taxa of the clade Australidelphia plus Caenolestes . The significant synapomorphies supporting this relationship are: enlargement of the fossa subarcuata that produces a bulbous ventral aspect of the mastoid and loss of post-temporal canal.  Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 85–115. No claim to original French government works.  相似文献   

13.
Abstract: Camposaurus arizonensis, a small theropod dinosaur from the early–middle Norian of Arizona (USA), is widely considered the oldest known neotheropod. However, despite its importance, Camposaurus is the subject of taxonomic and phylogenetic uncertainty and is often considered a nomen dubium, largely because of a fragmentary holotype. We here reassess the holotype of Camposaurus and identify two autapomorphies: the posterior edge of the tibial articular surface for the fibula offset as a sharp and prominent ridge and the absence of an anteriorly expanded medial condyle of the astragalus. We therefore consider Camposaurus to be a valid and diagnostic taxon of basal theropod dinosaur. For the first time, we include Camposaurus in a phylogenetic analysis, which confirms its neotheropod placement and recovers it as a close relative of Coelophysis rhodesiensis within Coelophysoidea sensu stricto. The position of Camposaurus as the oldest neotheropod provides an important calibration point, but necessitates long ghost lineages, indicating that our knowledge of the early evolutionary history of theropod dinosaurs is still patchy. Furthermore, our phylogenetic analysis recovers a polytomy at the base of Neotheropoda, as most parsimonious trees disagree in recovering a monophyletic or paraphyletic ‘traditional’ Coelophysoidea. This suggests that basal theropod phylogeny remains in a state of flux, and the monophyly of ‘traditional’ Coelophysoidea remains an open question.  相似文献   

14.
JISUO JIN 《Palaeontology》2012,55(1):205-228
Abstract: The most common forms of Late Ordovician dalmanellid brachiopods from the Cincinnatian type area, previously treated as either Dalmanella or Onniella, are assigned to Cincinnetina gen. nov. The new genus differs from Dalmanella and Onniella in having a consistently developed primary medial costa in the dorsal valve, a larger cardinal process that tends to develop a trilobed myophore, strongly differentiated fine and coarse punctae, and sparse aditicules. Cincinnetina can be distinguished from the closely related Paucicrura and Diceromyonia in its smaller trilobed cardinal process (when developed) that does not have a dominant medial lobe and does not extend into the delthyrial cavity of the ventral valve. Globally, Dalmanella and Onniella occur most commonly in deposits of relatively deep‐ or cool‐water palaeoecological settings, whereas in North America, Cincinnetina, Paucicrura and Diceromyonia are found mainly in carbonate‐rich deposits in warm‐water depositional environments, with Cincinnetina and Paucicrura most common in pericratonic settings and Diceromyonia in palaeoequatorial inland seas.  相似文献   

15.
The paper describes organic remains of one billion years old from the Lakhanda microbiota of the Uchur-Maya Region of southeastern Siberia. The microfossils were discovered on organic sapropelic films. The preserved morphological characters and some developmental stages of the ancient organisms, which are fixed in fossil state, suggest that some of them resembled zygomycetes. Other microfossils under consideration are comparable to reproductive structures of myxomycetes in the type of fusion of spheroid cells and formation of various types of aggregation (sori). Colonies of unicellular microfossils that are arranged in a branching pseudomycelium superficially resemble yeasts. The presence in the same biota of fungal remains belonging to the Myxomycota and Mycota, as well as members of xanthophyte vaucherian algae, indicates that various branches of eukaryotes might have developed in parallel even earlier than the Late Riphean.  相似文献   

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18.
The Evolution of Increased Competitive Ability (EICA) hypothesis suggests that plants from the invasive range should perform better than plants of the same species from the native range. To properly test this, we need to compare growth of plants from the two ranges in a common environment. Ideally, all the natural enemies should be excluded, to make sure that the differences are not due to different response of plants from the two ranges to the natural enemies. We used the above design to examine the difference in growth and reproduction in Cirsium arvense plants from the invasive (North America) and native range (Europe). To account for possible differences within the ranges, we used plants from two regions, separated by at least 1000 km, in each range. Because the higher performance of species from the invasive range can be caused by their higher ability to acquire resources we compared growth of the plants in two different nutrient levels. The results indicate that plants from the invasive range are larger in most size parameters as well as parameters more closely related to fitness. For aboveground biomass, the response of plants from the invasive range to nutrient addition was weaker than that of plants from the native range and the difference between the ranges was stronger in the nutrient poor substrate. The results are in agreement with the EICA hypothesis and suggest that plants from the invasive range have higher ability to use resources and are thus able to perform well also in nutrient poor conditions.  相似文献   

19.
The primary purpose of this publication is to make available two series of historical maps showing summer (April–September mean) temperatures over western Europe from A.D. 1750 and western North America from A.D. 1600. These maps have been reconstructed using networks of temperature-sensitive tree-ring chronologies as part of a continuing collaboration between the Swiss Federal Institute for Forest, Snow and Landscape Research (FSL) at Birmensdorf, Switzerland and the Climatic Research Unit (CRU) at the University of East Anglia, Norwich, U.K. The maps were reconstructed using relatively long maximum latewood density chronologies selected from the extensive networks of tree-ring data produced at the FSL. The reconstructions were produced using a spatial regression technique developed at CRU.The basis for the reconstructions are wood samples from various conifers growing at cool-moist sites close to the alpine or boreal timberlines. This material was analysed by x-ray densitometry and the resulting maximum latewood density chronologies were calibrated against meteorological data over a 100-year calibration period.These results emphasize the value of dendroclimatological research which can provide continentalscale reconstructions of past climate which represent a potential resource for climatologists, biologists, and historians with an interest in the spatial variability of summer temperatures over the middle to high latitudes.  相似文献   

20.
This review shows a close biogeographic connection between eastern Asia and western North America from the late Cretaceous to the late Neogene in major lineages of vascular plants (flowering plants, gymnosperms, ferns and lycophytes). Of the eastern Asian–North American disjuncts, conifers exhibit a high proportion of disjuncts between eastern Asia and western North America. Several lineages of ferns also show a recent disjunct pattern in the two areas. In flowering plants, the pattern is commonly shown in temperate elements between northeastern Asia and northwestern North America, as well as elements of the relict boreotropical and Neogene mesophytic and coniferous floras. The many cases of intercontinental biogeographic disjunctions between eastern Asia and western North America in plants supported by recent phylogenetic analyses highlight the importance of the Bering land bridge and/or the plant migrations across the Beringian region from the late Cretaceous to the late Neogene, especially during the Miocene. The Beringian region has permitted the filtering and migration of certain plant taxa since the Pliocene after the opening of the Bering Strait, as many conspecific taxa or closely related species occur on both sides of Beringia.  相似文献   

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