A new mammaliaform from the early Jurassic and evolution of mammalian characteristics     

Luo ZX  Crompton AW  Sun AL 《Science (New York, N.Y.)》2001,292(5521):1535-1540

A fossil from the Early Jurassic (Sinemurian, approximately 195 million years ago) represents a new lineage of mammaliaforms, the extinct groups more closely related to the living mammals than to nonmammaliaform cynodonts. It has an enlarged cranial cavity, but no postdentary trough on the mandible, indicating separation of the middle ear bones from the mandible. This extends the earliest record of these crucial mammalian features by some 45 million years and suggests that separation of the middle ear bones from the mandible and the expanded brain vault could be correlated. It shows that several key mammalian evolutionary innovations in the ear region, the temporomandibular joint, and the brain vault evolved incrementally through mammaliaform evolution and long before the differentiation of the living mammal groups. With an estimated body weight of only 2 grams, its coexistence with other larger mammaliaforms with similar "triconodont-like" teeth for insectivory within the same fauna suggests a great trophic diversity within the mammaliaform insectivore feeding guild, as inferred from the range of body sizes.  相似文献   

Use of REP‐PCR and 16S rRNA gene sequencing for comparison of Mannheimia haemolytica isolates obtained from fatal cases of bovine respiratory disease in the USA and Australia     

JD Taylor  DJ Doyle  PJ Blackall  AW Confer 《Australian veterinary journal》2014,92(1-2):15-23

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New fossil evidence on the sister-group of mammals and early mesozoic faunal distributions     

Shubin NH  Crompton AW  Sues HD  Olsen PE 《Science (New York, N.Y.)》1991,251(4997):1063-1065

Newly discovered remains of highly advanced mammal-like reptiles (Cynodontia: Tritheledontidae) from the Early Jurassic of Nova Scotia, Canada, have revealed that aspects of the characteristic mammalian occlusal pattern are primitive. Mammals and tritheledontids share an homologous pattern of occlusion that is not seen in other cynodonts. The new tritheledontids represent the first definite record of this family from North America. The extreme similarity of North American and African tritheledontids supports the hypothesis that the global distribution of terrestrial tetrapods was homogeneous in the Early Jurassic. This Early Jurassic cosmopolitanism represents the continuation of a trend toward increased global homogeneity among terrestrial tetrapod communities that began in the late Paleozoic.  相似文献   

Plasma protein electrophoresis as a prognostic indicator in Aspergillus species‐infected Gentoo penguins (Pygoscelis papua papua)          下载免费PDF全文

Adam D. Naylor  Simon J. Girling  Donna Brown  Claire G. Crompton  Romain Pizzi 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2017,46(4):605-614

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Alternative eucalypts for commercial pulpwood production at moderately dry sites in the warm temperate zone of KwaZulu-Natal,South Africa     

Robin AW Gardner  Keith M Little  Arnulf Kanzler  Thimagren N Naidoo 《Southern Forests》2018,80(2):115-129

During 2001, a series of four site–taxa interaction trials was established in the warm temperate (mean annual temperature range 16–19 °C) forestry climatic zone of KwaZulu-Natal (KZN), South Africa. The main objective was to investigate the commercial forestry potential of a range of alternative Eucalyptus and Corymbia taxa for moderately dry (mean annual precipitation < 850 mm) sites within the zone. At rotation end, all trials received final standing tree measurements. At one of the sites (Rockvale), trees of eight promising alternative taxa were felled, stem measurements and wood samples taken, and wood and fibre productivities determined. On the basis of tree growth and wood and fibre production, C. citriodora subsp. variegata, C. henryi, E. badjensis, E. benthamii and E. dorrigoensis (listed alphabetically) demonstrated the greatest potential as commercial alternatives for moderately dry sites in the KZN warm temperate zone. The majority of these taxa showed strong site specificity. Eucalyptus benthamii was the only taxon showing high growth adaptability to the entire range of site conditions applied in the series. The non-susceptibility of C. citriodora subsp. variegata and C. henryi to the current topical insect pests Thaumastocoris peregrinus, Leptocybe invasa and Glycaspis brimblecombei elevates the appeal of these taxa as potential alternative planting choices for moderately dry sites within lower altitude (<1 100 m asl) areas of the climate zone. The matching of the most promising alternative taxa in the series to the range of sites encountered in moderately dry areas of the KZN warm temperate forestry zone is discussed in this paper.  相似文献