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Cane rats (Thryonomyidae) are represented today by two species inhabiting sub-Saharan Africa. Their fossil record is predominately African, but includes several Miocene species from Arabia and continental Asia that represent dispersal events from Africa. For example, Paraulacodus indicus, known from the Miocene of Pakistan, is closely related to living Thryonomys. Here we describe a new thryonomyid, Protohummus dango, gen. et sp. nov., from the late Miocene Baynunah Formation of the United Arab Emirates. The new thryonomyid is less derived than “Thryonomysasakomae from the latest Miocene of Ethiopia and clarifies the origin of crown Thryonomys and the evolutionary transition from Paraulacodus. A phylogenetic analysis shows Protohummus dango to be morphologically intermediate between Paraulacodus spp. and extinct and living Thryonomys spp. The morphological grade and phylogenetic position of Protohummus dango further supports previous biochronological estimates of the age of the Baynunah Formation (ca. 6–8 Ma).  相似文献   
2.
ThepracticaluseofAzotobacterchroococcumasbiofertilizer hasbeenincreasinglyidentifiedinrecentyears.Oftentheefficacy ofthesebacteriaisassessedonthebasisofcropresponseswithout knowingthesurvival,persistenceandcompetitiveabilityofthein troducedstrain.Inoculat…  相似文献   
3.
Despite significant recent improvements to our understanding of the early evolution of the Order Proboscidea (elephants and their extinct relatives), geographic sampling of the group’s Paleogene fossil record remains strongly biased, with the first ~30 million years of proboscidean evolution documented solely in near-coastal deposits of northern Africa. The considerable morphological disparity that is observable among the late Eocene and early Oligocene proboscideans of northern Africa suggests that other, as yet unsampled, parts of Afro-Arabia might have served as important centers for the early diversification of major proboscidean clades. Here we describe the oldest taxonomically diagnostic remains of a fossil proboscidean from the Arabian Peninsula, a partial mandible of Omanitherium dhofarensis (new genus and species), from near the base of the early Oligocene Shizar Member of the Ashawq Formation, in the Dhofar Governorate of the Sultanate of Oman. The molars and premolars of Omanitherium are morphologically intermediate between those of Arcanotherium and Barytherium from northern Africa, but its specialized lower incisors are unlike those of other known Paleogene proboscideans in being greatly enlarged, high-crowned, conical, and tusk-like. Omanitherium is consistently placed close to late Eocene Barytherium in our phylogenetic analyses, and we place the new genus in the Family Barytheriidae. Some features of Omanitherium, such as tusk-like lower second incisors, the possible loss of the lower central incisors, an enlarged anterior mental foramen, and inferred elongate mandibular symphysis and diminutive P2, suggest a possible phylogenetic link with Deinotheriidae, an extinct family of proboscideans whose origins have long been mysterious.  相似文献   
4.
Journal of Material Cycles and Waste Management - In this study, an effort has been made to use concrete waste debris for the manufacturing of fly ash bricks as a sustainable material. Though in...  相似文献   
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