Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "R., D." wg kryterium: Autor

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 18
Tytuł:
A peculiar faunivorous metatherian from the early Eocene of Australia
Autorzy:
Beck, R.M.D.
Powiązania:
https://bibliotekanauki.pl/articles/945605.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Mammalia
Metatheria
Marsupialia
Sparassodonta
Archaeonothos henkgodthelpi
new species
Eocene
fossil
deposit
paleontology
Australia
Opis:
I describe Archaeonothos henkgodthelpi gen. et. sp. nov., a small (estimated body mass ~40–80 g) tribosphenic metatherian from the early Eocene Tingamarra Fauna of southeastern Queensland, Australia. This taxon, known only from a single isolated upper molar (M2 or M3) is characterised by a very distinctive combination of dental features that, collectively, probably represent faunivorous adaptations. These include: a straight, elevated centrocrista; a metacone considerably taller than the paracone; a wide stylar shelf (~50% of the total labiolingual width of the tooth); reduced stylar cusps; a long postmetacrista; a small and anteroposteriorly narrow protocone; an unbasined trigon; and the absence of conules. Some of these features are seen in dasyuromorphians, but detailed comparisons reveal key differences between A. henkgodthelpi and all known members of this clade. A. henkgodthelpi also predates recent molecular estimates for the divergence of crown-group Dasyuromorphia. Similar dental features are seen in a number of other metatherians, including the South American sparassodonts, Wirunodon chanku from the ?middle–late Eocene Santa Rosa local fauna of Peru, and Kasserinotherium tunisiense from the early Eocene Chambi fauna of Tunisia, although whether A. henkgodthelpi is closely related to any of these taxa is unclear based on available evidence. I therefore refer A. henkgodthelpi to Metatheria incertae sedis. Potential relatives of A. henkgodthelpi are unknown from any other Australian fossil deposit.
Źródło:
Acta Palaeontologica Polonica; 2015, 60, 1; 123-129
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New sharks and rays from the Cenomanian and Turonian of Charentes, France
Autorzy:
Vullo, R
Cappetta, H.
Neraudeau, D.
Powiązania:
https://bibliotekanauki.pl/articles/20707.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Turonian
Neoselachii
marine environment
Cenomanian
rajiform
Cretaceous
Rajiformes
taxonomy
Chondrichthyes
paleoenvironment
orectolobiform
Orectolobiformes
lamniform
new taxonomy
France
deposit
Lamniformes
Charente department
coastal environment
paleontology
Opis:
New or so far poorly known neoselachians from the Cenomanian and Turonian of SW France are described. The material studied herein comes from nine localities in the Charentes region, comprising palaeoenvironments ranging from coastal to open marine environments, and consists of two orectolobiforms, six lamniforms, and four rajiforms. The new taxa are Squalicorax coquandi sp. nov. and Roulletia bureaui gen. et sp. nov. within lamniforms, and Hamrabatis bernardezi sp. nov., Archingeayia sistaci gen. et sp. nov., and Engolismaia couillardi gen. et sp. nov. within rajiforms. New specimens of Odontaspis rochebrunei Sauvage, 1880 from the type area allow redescription of this taxon, assigned herein to the genus Cenocarcharias. Occurrences of Squalicorax baharijensis, S. cf. intermedius, and Archaeolamna sp., previously unrecorded from this region, and Almascyllium, a genus generally described from younger strata, are also noted, and improve knowledge of mid−Cretaceous selachian faunas from Western Europe.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The endocranium of the theropod dinosaur Ceratosaurus studied with computer tomography
Autorzy:
Sanders, R K
Smith, D.K.
Powiązania:
https://bibliotekanauki.pl/articles/22430.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
cranial pneumatic system
Ceratosaurus
virtual rendering
paleoneurology
Theropoda
theropod dinosaur
computer tomography
dinosaur
endocranium
paleontology
Opis:
A well preserved specimen of the theropod Ceratosaurusfrom the Upper Jurassic Morrison Formation of western Colorado was recently described and given the name C. magnicornis. The systematics of the genus is outside the scope of the present study but, as a generally accepted basal tetanuran, the braincase was CT scanned to provide a description of the endocranium, inner ear, pneumatic, and venous sinus systems in a primitive member of this clade. Five major subregions of the theropod endocranium are distinguished for the purpose of simplifying cranial computed tomographic interpretation and to provide a systematic means of comparison to other endocrania. The skull morphology of Ceratosaurus influences the overall braincase morphology and the number and distribution of the major foramina. The low pontine angle and relatively unflexed braincase is considered a more primitive character. The orientation of the horizontal semicircular canal confirms a rather horizontal and unerect posture of the head and neck. As in birds, the narrower skull morphology of Ceratosaurusis associated with fewer cranial nerve foramina. Additionally, the maxillary dominated dentigerous upper jaw of Ceratosaurusis felt to share with the alligator a large rostrally directed maxillary division of the trigeminal nerve and a small ophthalmic branch. The upper bill of birds, being dominated by the premaxillary and lacking teeth, is innervated predominantly by the ophthalmic division of the trigeminal nerve. For this reason, avian−based cranial nerve reconstructions are felt to be inappropriate for basal theropods.Ceratosaurusskull pneumatization and possible evidence of olfactory conchal structures is on the other hand very avian in character. Based on computed tomography, Ceratosaurusis determined to have possessed a typical basal theropod endocranium and bipedal vestibular system similar to Allosaurus.
Źródło:
Acta Palaeontologica Polonica; 2005, 50, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The extent of the pterosaur flight membrane
Autorzy:
Elgin, R.
Hone, D.
Frey, E.
Powiązania:
https://bibliotekanauki.pl/articles/23515.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
Reptilia
Pterosauria
flight
wing
Mesozoic
pterosaur
wing membrane
fossil
Opis:
The shape and extent of the membranous brachioptagium in pterosaurs remains a controversial topic for those attempting to determine the aerodynamic performance of the first vertebrate fliers. Various arguments in favour of the trailing edge terminating against either the torso or hip, the femur, the ankle, or different locations for various taxa, has resulted in several published reconstructions. Uncertainty over the correct model is detrimental to both aerodynamic and palaeoecological studies that are forced to simultaneously consider multiple and highly variable configurations for individual taxa. A review of relevant pterosaur specimens with preserved soft tissues or impressions of the wing membrane, however, strongly suggests that the trailing edge of the wing extended down to the lower leg or ankle in all specimens where the brachiopatagium is completely preserved. This configuration is seen across a phylogenetically broad range of pterosaurs and is thus likely to have been universally present throughout the Pterosauria. Support for opposing hypotheses where the trailing edge terminates against the body, hip, or knee are based on several specimens where the wing membrane is either incomplete or has undergone post−mortem contraction. An ankle attachment does not rule out a high aspect ratio wing as the curvature of the trailing edge and the ratio of the fore to hind limbs also play a major role in determining the final shape of the membrane.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new large-bodied theropod dinosaur from the Middle Jurassic of Warwickshire, United Kingdom
Autorzy:
Benson, R.B.J.
Radley, J.D.
Powiązania:
https://bibliotekanauki.pl/articles/22445.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
large-bodied dinosaur
dinosaur
new dinosaur
theropod dinosaur
Middle Jurassic
Jurassic
Warwickshire
United Kingdom
paleontology
Dinosauria
Theropoda
Tetanurae
Megalosaurus
Cruxicheiros
Bathonian
Chipping Norton Limestone Formation
Opis:
Previously undocumented postcranial material from the Chipping Norton Limestone Formation (Middle Jurassic: Lower Bathonian) of Cross Hands Quarry, near Little Compton, Warwickshire represents a new large−bodied theropod dinosaur, distinct from the contemporaneous Megalosaurus bucklandii. Cruxicheiros newmanorum gen. et sp. nov. is diagnosed by a single autapomorphy, the presence of a proximomedially inclined ridge within the groove that marks the lateral extent of the posterior flange of the femoral caput (trochanteric fossa). C. newmanorum shows three tetanuran features: widely separated cervical zygapophyses, a swollen ridge on the lateral surface of the iliac blade and an anterior spur of the caudal neural spines. However, due to fragmentary preservation its affinities within Tetanurae remain uncertain: phylogenetic analysis places it as the most basal tetanuran, the most basal megalosauroid (= spinosauroid) or the most basal neotetanuran.
Źródło:
Acta Palaeontologica Polonica; 2010, 55, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new leanchoiliid megacheiran arthropod from the lower Cambrian Emu Bay Shale, South Australia
Autorzy:
Edgecombe, G.D.
Garcia-Bellido, D.C.
Paterson, J.R.
Powiązania:
https://bibliotekanauki.pl/articles/21269.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new arthropod
arthropod
leanchoiliid megacheiran arthropod
Lower Cambrian
Cambrian
South Australia
paleontology
Arthropoda
Megacheira
Leanchoiliidae
Oestokerkus
Leanchoilia
Alalcomenaeus
midgut gland
phylogenesis
Opis:
The Leanchoiliidae is well−known from abundant material of Leanchoilia, from the Burgess Shale and Chengjiang Konservat−Lagerstätten. The first Australian member of the group is Oestokerkus megacholix gen. et sp. nov., described from the Emu Bay Shale (Cambrian Series 2, Stage 4), at Buck Quarry, Kangaroo Island, South Australia, and is intermediate in age between the well known leanchoiliid species from the Burgess Shale and Chengjiang. Phylogenetic analysis of “short great appendage” arthropods (Megacheira) in the context of the chelicerate stem group resolves the Australian species as sister to Burgess Shale, Utah, and Chengjiang Leanchoilia species, but most readily distinguished from Leanchoilia and Alalcomenaeus by a different telson shape, interpreted as being forked, widening distally, and with a few dorsally curved spines at the posterior angle. Leanchoiliid interrelationships are stable to alternative character weights, and Megacheira corresponds to a clade in most analyses.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A dental microwear texture analysis of the Mio-Pliocene hyaenids from Langebaanweg, South Africa
Autorzy:
Stynder, D.D.
Ungar, P.S.
Scott, J.R.
Schubert, B.W.
Powiązania:
https://bibliotekanauki.pl/articles/23002.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
dental microwear texture
Mio-Pliocene
Hyaenidae
Langebaanweg
South Africa
Mammalia
durophagy
diet
foraging strategy
Hyaenictitherium namaquensis Ikelohyaena abronia
Chasmaporthetes australis
Hyaenictis hendeyi
Crocuta crocuta
Acinonyx jubatus
Panthera leo
paleontology
hyaenid species
Opis:
Hyaenids reached their peak diversity during the Mio−Pliocene, when an array of carnivorous species emerged alongside dwindling civet−like and mongoose−like insectivorous/omnivorous taxa. Significantly, bone−cracking morphological adaptations were poorly developed in these newly−emerged species. This, their general canid−like morphology, and the absence/rarity of canids in Eurasia and Africa at the time, has led researchers to hypothesise that these carnivorous Mio−Pliocene hyaenas were ecological vicars to modern canids. To shed further light on their diets and foraging strategies, we examine and compare the dental microwear textures of Hyaenictitherium namaquensis, Ikelohyaena abronia, Chasmaporthetes australis, and Hyaenictis hendeyi from the South African Mio−Pliocene site of Langebaanweg with those of the extant feliforms Crocuta crocuta, Acinonyx jubatus, and Panthera leo (caniforms are not included because homologous wear facets are not directly comparable between the suborders). Sample sizes for individual fossil species are small, which limits confidence in assessments of variation between the extinct taxa; however, these Mio−Pliocene hyaenas exhibit surface complexity and textural fill volume values that are considerably lower than those exhibited by the living hyaena, Crocuta crocuta. Dental microwear texture analysis thus supports interpretations of craniodental evidence suggesting low bone consumption in carnivorous Mio−Pliocene hyaenas.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Crouching theropod and Navahopus sauropodomorph tracks from the Early Jurassic Navajo Sandstone of USA
Autorzy:
Milan, J
Loope, D.B.
Bromley, R.G.
Powiązania:
https://bibliotekanauki.pl/articles/21900.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Navajo Sandstone Formation
Navahopus coyoteensis
Early Jurassic
crouching trace
paleontology
Navahopodidae
sauropodomorph track
ichnology
Southern Utah
USA
theropod dinosaur
Theropoda
trackway
locomotory habit
Sauropodomorpha
Navahopus
Jurassic
Northern Arizona
remains
theropod track
Opis:
Numerous tracks and trackways are preserved in the a cross−strata of the Lower Jurassic Navajo Sandstone of northern Arizona and southern Utah, USA. Tracks and trackways of small theropod dinosaurs are particularly abundant within one 10−m−thick interval. This paper describes a crouching trace from a theropod dinosaur that shows impressions of all four limbs, the ischial callosity, the tail, and tracks leading to and away from the crouching site, and revises the interpretation of a well preserved trackway hitherto referred to the synapsid ichnogenus Brasilichnium and here considered to be from a sauropodomorph dinosaur. It is named Navahopus coyoteensisisp. nov. on the basis of morphological differences from the type ichnospecies N. falcipollex. The ichnofamily Navahopodidae is revised to include Tetrasauropous unguiferus, Navahopus falcipollex, and N. coyoteensis.
Źródło:
Acta Palaeontologica Polonica; 2008, 53, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new species of the suid genus Kolpochoerus from Ethiopia
Autorzy:
Souron, A.
Boisserie, J.-R.
White, T.-D.
Powiązania:
https://bibliotekanauki.pl/articles/945607.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new species
Kolpochoerus
Mammalia
Suinae
Hylochoerus
Potamochoerus
Pliocene
Pleistocene
Awash River
paleontology
Ethiopia
Opis:
Although the suid genus Kolpochoerus is well known from the Plio-Pleistocene of Africa, the evolutionary history of one of its constituent species, K. majus, remained obscure until substantial fossil evidence accumulated during the last 20 years, largely from sites in Ethiopia. Here, we describe Kolpochoerus phillipi sp. nov., based on a fairly complete skull and the remains of additional individuals from ~2.5 Ma deposits at Matabaietu, in the Middle Awash study area of Ethiopia. Based on a phylogenetic analysis, we suggest that K. phillipi sp. nov. belongs to a clade of “bunolophodont suines” including K. majus and the extant giant forest hog Hylochoerus meinertzhageni. Within this clade, K. phillipi sp. nov. likely represents a potential ancestor of K. majus, based on its morphology and stratigraphic position.
Źródło:
Acta Palaeontologica Polonica; 2015, 60, 1; 80-96
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The dinosaur Hadrosaurus foulkii, from the Campanian of the East Coast of North America, with a reevaluation of the genus
Autorzy:
Prieto-Marquez, A
Weishampel, D.B.
Horner, J.R.
Powiązania:
https://bibliotekanauki.pl/articles/21591.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
phylogenesis
East Coast
Cretaceous
skeletal element
Hadrosauridae
dinosaur
Hadrosaurus foulkii
North America
paleontology
Opis:
Hadrosaurus foulkii was the first dinosaur known outside Europe from partially complete skeletal elements. It is the holotype of the family Hadrosauridae and the subfamily Hadrosaurinae. The history of its discovery and taxonomy is reviewed, and the holotype of H. foulkii is redescribed. The holotype of H. foulkii lacks distinguishing characters; therefore, this taxon is a nomen dubium. It is not synonymous with species of Gryposaurus and/or Kritosaurus. We also reevaluate the taxonomy and osteology of H. tripos, H. minor, H. cavatus, H. breviceps, H. paucidens, and Ornithotarsus immanis. In agreement with previous studies, these taxa are considered nomina dubia due to the absence of distinguishing characters and are therefore referrable only to Hadrosauridae indeterminate; H. paucidensis referrable to Lambeosaurinae indeterminate. Finally, our phylogenetic analysis indicates that the holotype of H. foulkii belongs to a member of Euhadrosauria and, tentatively, of Hadrosaurinae.
Źródło:
Acta Palaeontologica Polonica; 2006, 51, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New data on the Paleocene monotreme Monotrematum sudamericanum, and the convergent evolution of triangulate molars
Autorzy:
Pascual, R
Goin, F.J.
Balarino, L.
Udrizar Sauthier, D.E.
Powiązania:
https://bibliotekanauki.pl/articles/21782.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Monotremata
molar
Paleocene
Gondwana
triangulate molar
Monotrematum sudamericanum
monotreme
molar structure
evolution
Patagonia
paleontology
Opis:
We describe an additional fragmentary upper molar and the first lower molar known of Monotrematum sudamericanum, the oldest Cenozoic (Paleocene) monotreme. Comparisons suggest that the monotreme evolution passed through a stage in which their molars were “pseudo−triangulate”, without a true trigonid, and that the monotreme pseudo−triangulate pattern did not arise through rotation of the primary molar cusps. Monotreme lower molars lack a talonid, and consequently there is no basin with facets produced by the wearing action of a “protocone”; a cristid obliqua connecting the “talonid“ to the “trigonid” is also absent. We hypothesize that acquisition of the molar pattern seen in Steropodon galmani (Early Cretaceous, Albian) followed a process similar to that already postulated for docodonts (Docodon in Laurasia, Reigitherium in the South American sector of Gondwana) and, probably, in the gondwanathere Ferugliotherium.
Źródło:
Acta Palaeontologica Polonica; 2002, 47, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new basal sphenacodontid synapsid from the Late Carboniferous of the Saar-Nahe Basin, Germany
Autorzy:
Frobisch, J.
Schoch, R.
Muller, J.
Schindler, T.
Schweiss, D.
Powiązania:
https://bibliotekanauki.pl/articles/22246.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Carboniferous
Cryptovenator hirschbergeri
Germany
Late Carboniferous
phylogenetic relationship
Saar−Nahe Basin
Sphenacodontidae
Synapsida
geological setting
new species
paleontology
sediment
sphenacodontid synapsid
systematics
taxonomy
Opis:
A new basal sphenacodontid synapsid, represented by an anterior portion of a mandible, demonstrates for the first time the presence of amniotes in the largest European Permo−Carboniferous basin, the Saar−Nahe Basin. The new taxon, Cryptovenator hirschbergeri gen. et sp. nov., is autapomorphic in the extreme shortness and robustness of the lower jaw, with moderate heterodonty, including the absence of a greatly reduced first tooth and only a slight caniniform development of the second and third teeth. Cryptovenatorshares with Dimetrodon, Sphenacodon, and Ctenospondylus, but notably not with Secodontosaurus, enlarged canines and a characteristic teardrop outline of the marginal teeth in lateral view, possession of a deep symphyseal region, and a strongly concave dorsal margin of the dentary. The new find shows that sphenacodontids were present in the Saar−Nahe Basin by the latest Carboniferous, predating the record of sphenacodontid tracks from slightly younger sediments in this region.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An aberrant amphicyonid mammal from the latest Eocene of the Bose Basin, Guangxi, China
Autorzy:
Zhai, R
Ciochon, R.L.
Tong, Y.
Savage, D.E.
Morlo, M.
Holroyd, P.A.
Gunnell, G.F.
Powiązania:
https://bibliotekanauki.pl/articles/22578.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Amphicyonidae
Eocene
mammal
China
Carnivora
Guangxi
amphicyonid mammal
Nadu Formation
Bose Basin
paleontology
Opis:
A new genus and species of an amphicyonid from the Bose Basin of Guangxi, south China, is short−jawed with relatively bunodont cheek teeth that are characterized by reduction in cusp number. This taxon is the oldest record of an amphicyonid from south Asia and possibly for all of Asia. Despite its antiquity, it is derived in the development of brachygnathy and differs from other early amphicyonids that have shortened faces. Evidently brachygnathy was established in this species without loss of p1–2 or m2–3, which became single−rooted from a primitive double−rooted condition.
Źródło:
Acta Palaeontologica Polonica; 2003, 48, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First tillodont from India: Additional evidence for an early Eocene faunal connection between Europe and India?
Autorzy:
Rose, K D
Rana, R.S.
Sahni, A.
Kumar, K.
Singh, L.
Smith, T.
Powiązania:
https://bibliotekanauki.pl/articles/22886.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
paleontology
tillodont
India
Europe
Eocene
Paleocene
faunal connection
Cenozoic
mammal
Ypresian
anthracobunid
lagomorph
fauna
Opis:
Vastan Lignite Mine in southeastern Gujarat, India, produces the oldest known Cenozoic land−mammals and the only early Eocene continental vertebrate fauna known from India (e.g., Bajpai et al. 2005; Rana et al. 2005, 2008; Rose et al. 2006, 2008, 2009; Smith et al. 2007; Rage et al. 2008). The fauna comes from the Cambay Shale Formation and has been dated as middle Ypresian (~52 Ma, early Cuisian) based on a common nummulitid foraminiferan from about 15 m above the vertebrate−producing layer (Sahni et al. 2006; Rana et al. 2008). However, a recent study of dinoflagellate cysts from the section suggests that the deposits may be as old as 54–55 Ma (Garg et al. 2008). Although some elements of the fauna, such as anthracobunids and lagomorphs, have Asian affinities, a surprising number of taxa among the snakes, bats, insectivores, primates, rodents, and artiodactyls appear to be most closely related to early Eocene European or North American taxa. This may simply reflect the poor state of knowledge of contemporary south Asian vertebrate faunas; alternatively, it might be evidence of previously unsuspected early Eocene faunal exchange between Europe and southwest Asia. We report here two teeth of a tillodont from Vastan Mine, which constitute the first record of the mammalian order Tillodontia known from India. Despite the much greater generic diversity of tillodonts in Asia than elsewhere, the Vastan tillodont shows clear affinities with Euramerican esthonychines.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 2; 351-355
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fractal analysis of ostracod shell variability: A comparison with geometric and classic morphometrics
Autorzy:
Aiello, G
Barattolo, F.
Barra, D.
Fiorito, G.
Mazzarella, A.
Raia, P.
Viola, R.
Powiązania:
https://bibliotekanauki.pl/articles/22918.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
fractal analysis
variability
statistical method
systematics
Krithe compressa
ostracod
shell
Ostracoda
morphometry
morphological variability
Krithe iniqua
paleontology
Opis:
Two statistical methods, fractal geometry and geometric morphometrics, are tested for their applicability to ostracod systematics. For this comparison, two morphologically similar ostracod species (Krithe compressa and Krithe iniqua) whose genus−level systematics is still incompletely resolved, are selected. Twenty−nine right valves of each species were collected from the upper Pliocene samples at the Monte San Nicola section in southern Italy. Statistical analyses (MANOVA on morphometric shape variables, and D values) were utilized to test if geometric morphometrics and fractal analysis are appropriate into discriminating between the two species. Both methods succeeded in distinguishing the species statistically. The fractal analysis of the two ostracod species shows D values centered on 1.31±0.02 for Krithe iniqua and on 1.40±0.02 for Krithe compressa. Geometric morphometric analysis indicates significant differences between the two species and allows studying intra−populational variability as well as. The most variable traits indicated by geometric morphometrics are vestibular area and posterior outline of the shell, indicating that these traits are the most relevant for the systematics of the species analyzed. Both fractal geometry and geometric morphometrics provide a measure of population variability. Fractal analysis has the advantage of being free from any subjectivity in the selection of characters and could be most appropriate to use for analysis of complex ornamentation for systematic purposes. However, a possible advantage of geometric morphometrics over fractal analysis is its ability to indicate where statistically significant variations in shape occur on the shell.
Źródło:
Acta Palaeontologica Polonica; 2007, 52, 3
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 18

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies