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1.
John Rowden 《Zoo biology》2001,20(2):123-125
A review of Trogons and Quetzals of the World by Paul A. Johnsgard. Washington, DC: Smithsonian Institution Press, 2000, 223 pp., $49.95, hardbound.  相似文献   

2.
A simple model for the immission of pollen grains from large area sources into the atmospheric convective boundary layer is presented.

The terrain is assumed to be homogeneous (like a large plain) and the sources are assumed to be uniform over horizontal distances of the order of 10 km.

The model requires the production rate of pollen to be specified, as well as the temperature as a function of time or analogous atmospheric parameters.

The results compare well with data measured in the Po Valley, Italy.  相似文献   

3.
The occurrence of Cercidiphyllum -like leaves, infructescences, fruits and seeds in the British early Tertiary is reviewed. Material previously described from the London Clay Formation, Lower Headon Beds (upper Barton Formation), Oldhaven Formation, and Woolwich and Reading Formation, are evaluated along with specimens from a new late Palaeocene locality in the Reading Beds. The leaves are assigned to Trochodendroides prestwichii; and infructescences, fruits and seeds, previously assigned to Carpolithus gardneri and Jenkinsella apocynoides , are united as a single species Nyssidium arcticum. The evidence that Trochodendroides and Nyssidium are parts of a single kind of fossil plant is supported, and the reconstructed ' Nyssidium plant' is compared with extant taxa, particularly extant Cercidiphyllum. The fossil plant shows a combination of characters not seen in any living genus, and the structure of the infructescence, as well as other features, precludes placing it within Cercidiphyllum. 'Nyssidium' and Cercidiphyllum are closely related. The morphological and sedimentological evidence indicates that 'Nyssidium' was an important colonizer of a variety of open flood-plain environments during the early Tertiary.  相似文献   

4.
Migmaster angularis n. gen. n. sp. (Trichasteropsiidae, Forcipulatacea, Asteroidea) is described from the German Triassic Lower Muschelkalk of Anisian (Pelsonian) age, and new specimens ofTrichasteropsis bielertorum broaden understanding of this species. Phylogenetic events linking the stem groups, known only from Paleozoic rocks, with the crown group, known only from post-Paleozoic rocks, are problematic; the new fossils partially constrain phylogenetic changes associated with emergence of crown-group asteroids.   相似文献   

5.
The biogeographic affinities of the Cretaceous and early Tertiary angiosperm floras of the North American area (which includes Meso-America, and the Greater Antilles) have been the subject of considerable interest. Although recent treatments of isolated taxa have shown affinities between North American, European, east Asian and Neotropic floras, the relationships have not been quantified. This study compiles the records of fossils whose familial relationships seem secure. This provides a carefully culled, and uniformly presented review of the Cretaceous and Paleogene record from 1950 to 1989 and supplements LaMotte (1950). A subset of these records, which showed compelling evidence of subfamilial relationships, was analyzed to quantify the relationships of the Cretaceous, Paleocene, Eocene and Oligocene floras to other regions. The analysis suggests that for the entire period 24% of the fossil species had affinities with extant taxa from the Northern Hemisphere; 10% with taxa from the Northern Hemisphere that have a few species in South America; 17% with taxa from Eurasia; 3% with taxa with a disjunct Eurasian-South American pattern; 19% with taxa from South America and/or Africa; 8% with taxa from South America and/or Africa that have an important sister group in southeast Asia; 5% with taxa from the Old World; and 13% with taxa having other distribution patterns. Those fossils with affinities to Laurasian taxa are mostly found in the northern and western portions of the North American area. The fossils with affinities to South American and/or African taxa are found in the southern portions of North America, Meso-America, and the Greater Antilles. The taxa with disjunct distributions show both patterns. These patterns suggest that during this time there were wide-spread temperate elements, found throughout Laurasia; Boreotropical flora elements, distributed in North America, Europe and along the Tethys seaway to southeast Asia; and West Gondwana elements which show dispersion from South America across the proto-Caribbean. The paleobotanical data are compatible with current geological, paleontological and biogeographical studies.  相似文献   

6.
Robert T. Clarke 《Grana》2013,52(3):544-546
Peregrinipollis nigericus gen. et sp. nov., a tricolpate palynomorph with reticulate and granulate-verrucose sculpture, is described from Upper Tertiary sediments of Nigeria.  相似文献   

7.
Hyracotherium cuniculus Owen, 1842, from Palaeocene–Eocene boundary strata in NW Europe, was formerly considered to be an equoid. It is here placed in Cymbalophus gen. nov. , in the perissodactyl suborder Ceralomorpha, which comprises tapiroids and rhinocerotoids, as one of its most primitive and earliest members. This revised classification is based on an evaluation of its advanced versus primitive character states, and comparison with a variety of other primitive perissodactyls. Cheek tooth occlusal relationships in the early stages of ceratomorph evolution are discussed and contrasted with the fundamental perissodactyl morphotype as represented in Hyracotherium. It is suggested that the Lophiodontidae (formerly considered to be ceratomorphs; may be more closely related to chalicotheres; that the Isectolophidae may be the sister-group of chalicotheres and lophiodonts plus ceratomorplis; and that Cymbalophus is the most primitive known member of the newly restricted Ceratomorpha. Cymbalophus is placed tentatively in the family Helaletidae.  相似文献   

8.
Although trogons (Aves, Trogonidae) are well characterized by the possession of heterodactyl feet, their phylogenetic relationships to other extant birds still are only poorly understood. Molecular studies did not show conclusive results and there are amazingly few comparative studies of the anatomy of trogons. Virtually the only hypothesis on trogon relationships that was supported with derived morphological characters is a sister group relationship to alcediniform birds (bee-eaters, kingfishers, and allies), which share a derived morphology of the columella (ear-ossicle) with trogons. However, in this study a very similar columella is reported for the oilbird (Steatornithidae) and additional previously unrecognized derived osteological characters are presented, which are shared by trogons and oilbirds. A numerical cladistic analysis of 28 morphological characters also resulted in monophyly of Trogonidae and Steatornithidae, although the corresponding node was not retained in a bootstrap analysis.  相似文献   

9.
The Turkish community in Germany is fractured along ethnic, class, religious, and generational lines, although the practice of reciprocity provides stability and continuity in ethnic identification. Turks are also categorized by German discourses, which shifted after reunification, incorporating Turks into an anxiety-laden east-west problematic. Turkish responses to antiforeigner violence reflect ethnicity both as category and as practice: withdrawal behind communal boundaries or creation of a transnational creole ethnic self around the practice of reciprocity.  相似文献   

10.
Patrick Pineker  Thomas Mörs 《Geobios》2011,44(2-3):279-287
The dental material described in this paper represents the largest known sample of molar material of the extinct platacanthomyine rodent Neocometes Schaub and Zapfe. It can be attributed to Neocometes similis Fahlbusch, the stratigraphically oldest and most primitive of the two species recognized in the European Miocene. This rich material provides sufficient samples of all molar positions to evaluate and confirm the morphologic and morphometric characters given for N. similis. The evolutionary stage of the Neocometes population from Echzell is only slightly more derived than the one from the type locality Erkertshofen 2, and supports the biostratigraphic setting of Echzell given by earlier authors. N. similis is the first mammal described in detail from the fossiliferous ash layers of Echzell, a locality situated at the southwestern margin of the Vogelsberg volcanic complex in central Germany.  相似文献   

11.
12.
New early Miocene forelimb fossils have been recovered from the Songhor and Lower Kapurtay localities in southwestern Kenya. We describe four specimens that are similar in size and functional capabilities. Their specific allocation is problematic but these forelimb specimens must belong to either Rangwapithecus gordoni or Proconsul africanus. If these new postcranial specimens should belong to R. gordoni, on the basis of size and common dental specimens found at Songhor, they represent a new elbow complex. The morphology of these fossils is anatomically and functionally similar to that of Proconsul. The proconsuloid elbow complex allows extensive forelimb rotations and is capable of performing arboreal quadrupedalism and climbing activities. No suspensory adaptations are apparent. The proconsuloid elbow complex remains a good ancestral condition for hominoid primates.  相似文献   

13.
Abstract

The family Seguenziidae is represented in the New Zealand region by the following new species (fossil taxa asterisked): Seguenzia glabella*, S. prisca*, S. serrata*, S. conopia, S. fulgida, S. chelina, S. transenna, S. textilis, S. compta; Seguenziella (n.gen.) patula; Seguenziopsis (n.gen.) bicorona; Carenzia venusta, C. fastigiata; Thelyssina (n.gen.) sterrha; Ancistrobasis dilecta, A. regina; Fluxinella (n.gen.) lepida, F. lenticulosa, F. maxwelli*; Calliobasis (n.gen.) eos*, C. chlorosa, C. miranda.  相似文献   

14.
High-level phylogeny of early Tertiary rodents: dental evidence   总被引:1,自引:0,他引:1  
Major crown‐groups of rodents were well established in the early Tertiary, and fossils provide an invaluable window into their evolutionary history. The main focus of this project was to perform a cladistic assessment of the dental evidence for early Tertiary rodent cladogenesis – the masticatory apparatus and teeth are the most frequently preserved anatomical features in the fossil record. We focused on groups that existed in a period corresponding to their early history, combining fossils belonging to extinct lineages and to stem‐groups leading to modern lineages. While the monophyly of some groups is not systematically explored, our results have important implications for high‐level rodent relationships and systematics. These results are consistent with those of recent molecular phylogenies and reliably congruent with the stratigraphic record, thus enhancing the pertinence of dental characters for phylogenetic inference. Our approach provides evidence of a fundamental dichotomy in early rodent history. Two major clades have been identified: (1) the earliest ‘ctenodactyloid’ (Ctenodactylidae, Chapattimyidae, Yuomyidae, Diatomyidae) and hystricognathous (Tsaganomyidae, Baluchimyinae, ‘phiomorphs’, ‘caviomorphs’) rodents, and (2) the earliest ‘ischyromyoid’ rodents with their closest relatives (Muroidea + Dipodoidea + Geomyoidea + Anomaluroidea + Castoroidea + Sciuravidae + Gliroidea, and Sciuroidea + Aplodontoidea + Theridomorpha). This topology has led us to endorse Ctenohystrica as the first clade and propose a new taxon, Ischyromyiformes, for the second. Although minimized in our working hypothesis, the homoplasy in dental characters remains significant. However, a number of homoplasic characters reveal structuring in their internal distribution, allowing us to discern evolutionary morphological patterns, notably the pentalophodonty of molars, zygomasseteric complex and incisor enamel microstructure. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 142 , 105–134.  相似文献   

15.
GERALD MAYR 《Ibis》2009,151(2):392-395
A tarsometatarsus of a diminutive representative of the Phalacrocoracoidea, the clade including the Phalacrocoracidae (cormorants) and Anhingidae (anhingas), is described from the early Miocene of Germany. The fossil is assigned to a new species Limicorallus (?) carbunculus, and closely resembles the tarsometatarsus of extant Phalacrocoracidae in overall morphology. Limicorallus (?) carbunculus is the smallest representative of the Phalacrocoracoidea, reaching only two‐thirds the size of the extant Pygmy Cormorant Phalacrocorax pygmeus. By significantly lowering the minimum size of the Phalacrocoracoidea, this new species adds to our knowledge of the early diversity of this clade.  相似文献   

16.
A complete tarsometatarsus of a passerine bird from the early Miocene (MN 3) of Petersbuch (Bavaria, Germany) is identified as an extinct representative of the climbing Certhioidea, i.e., a clade comprising treecreepers (Certhiidae), nuthatches and wallcreepers (Sittidae). The fossil specimen represents the so far earliest evidence of a representative of the Certhioidea and is described as †Certhiops rummeli gen. et sp. nov. Similarities to other climbing passerines are discussed.  相似文献   

17.
The dental material described in this paper was collected from fossiliferous ash layers of the Vogelsberg volcanic complex at Echzell, Germany. It consists of 32 teeth of a new large Apeomys species, Apeomys oldrichi n. sp., and 19 teeth of Megapeomys lindsayi Fejfar, Rummel and Tomida. Both species are extremely rare faunal elements in the early Miocene of Europe. Apeomys oldrichi n. sp. is the largest known Apeomys species, and occurs in a number of MN 3 – 4 sites in southern Germany and Czech Republic. Megapeomys lindsayi, the largest Eurasian apeomyine, was described on the basis of a single lower premolar. Herein both lower and upper cheek teeth as well as the lower deciduous premolar are described for the first time. In comparison with related populations from other localities, the evolutionary stage of the two apeomyine species clearly indicates a middle Orleanian age (MN 4) for Echzell which concurs with previous studies.

http://zoobank.org/urn:lsid:zoobank.org:pub:1F9E49BE-C4B6-4597-A116-234E13D86BA9  相似文献   


18.
COLLINSON  M. E. 《Annals of botany》1978,42(1):233-250
Dispersed fern sporangia have been recovered from the BembridgeMarls of the Isle of Wight and from Bracklesham deposits ina borehole West of Poole, Dorset. These fern sporangia confirmthe presence of the family Polypodiaceae s.1. in the BritishTertiary flora. Previously records of this family have beenbased solely on vegetative material, usually fragmentary, forwhich taxonomic assignment is inevitably insecure. The sporangia,containing spores and with adherent paraphyses, are shown tobe most comparable with the Recent genus Acrostichum L. andare described as Acrostichum anglicumsp. nov. The distributionand occurrence of these sporangia suggests the extensive developmentof Acrostichum in the lacustrine environments of Bembridge times.  相似文献   

19.
Two new fossil members of the subfamily Myrmeciinae are described: Archimyrmex wedmannae, sp. nov (Grube Messel, Germany, Middle Eocene) and Prionomyrmex wappleri, sp. nov. (Rott, Germany, Late Oligocene). Members of the genus Archimyrmex were known earlier from Eocene deposits of the United States and Argentina, and members of the genus Prionomyrmex were known from Late Eocene Baltic amber.  相似文献   

20.
Late Mesozoic palaeobiogeography has been characterized by a distinction between the northern territories of Laurasia and the southern landmasses of Gondwana. The repeated discovery of Gondwanan lineages in Laurasia has led to the proposal of alternative scenarios to explain these anomalous occurrences. A new biogeographical model for late Mesozoic terrestrial ecosystems is here proposed in which Europe and "Gondwanan" territories possessed a common Eurogondwanan fauna during the earliest Cretaceous. Subsequently, following the Hauterivian, the European territories severed from Africa and then connected to Asiamerica resulting in a faunal interchange. This model explains the presence of Gondwanan taxa in Laurasia and the absence of Laurasian forms in the southern territories during the Cretaceous. In order to test this new palaeobiogeographical model, tree reconciliation analyses (TRAs) were performed based on biogeographical signals provided by a supertree of late Mesozoic archosaurs. The TRAs found significant evidence for the presence of an earliest Cretaceous Eurogondwanan fauna followed by a relatively short-term Gondwana-Laurasia dichotomy. The analysis recovered evidence for a biogeographical reconnection of the European territories with Africa and South America-Antarctica during the Campanian to Maastrichtian time-slice. This biogeographical scenario appears to continue through the early Tertiary and sheds light on the trans-Atlantic disjunct distributions of several extant plant and animal groups.  相似文献   

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