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Darwin described the Cretaceous diversification and subsequent rapid rise of flowering plants (angiosperms) as an “abominable mystery”: how could they have achieved worldwide ecological dominance by early Paleogene times when the oldest angiosperm fossils are only Cretaceous in age? However, recent phylogenetic and palaeobiogeographical analyses have suggested a much earlier, perhaps Triassic origin for the stem angiosperms. We suggest that the fossil record is accurately reflecting the rapid diversification of the crown angiosperms that molecular data suggests occurred in Cretaceous–early Palaeogene times, and which coincides with similar explosive diversifications that occurred in other parts of the terrestrial biota including insects, birds and mammals. Early, stem angiosperms are poorly represented in the fossil record for a combination of taphonomic and ecological reasons. We conclude that the reported evidence shows that the Darwin's “mystery” is in fact no mystery and confirms that it merely requires an appropriate reading of the fossil record.  相似文献   
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This study presents the first report of mesofossils of flowers, fruits and seeds found in the Cretaceous of New Zealand. The specimens were recovered from the Late Cretaceous (Maastrichtian, ca. 70 Ma) at Kai Point Mine, South Island in a sequence of floodplain sediments sampled just below the Barclay Coal Seam. Angiosperm flowers, fruits and seeds occur in the sample. The most common form is an actinomorphic flower with two whorls of three tepals. Anther bases are preserved and the ovary develops into a drupe, all features that are consistent with placement in the Lauraceae. Reproductive structures including seeds of conifers are also described, with some allied to the Podocarpaceae. This contrasts with interpretations of the flora based on macrofossils that indicate abundant Araucariaceae and highlights the different perspectives that mesofossil floras give to any assemblage. The results of the present study support a Late Cretaceous flora at this site mainly dominated by conifers with affinities to Podocarpaceae but also including lauraceous angiosperms.  相似文献   
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《China Geology》2020,3(1):8-15
Frugivory is an important ecological tie between animals and angiosperms. It plays an important role in the evolution of food webs and energy flow networks in the ecosystem. However, little is known about how old this relationship can be due to lack of relevant fossil evidence. Here, the authors report a fossil fruit, Jurafructus gen. nov., a putative angiosperm from the Middle–Late Jurassic (>164 Ma) of Daohugou Village, Inner Mongolia, China, which provides the currently earliest evidence of frugivory. The fossil is a more or less three-dimensionally preserved coalified drupe that has been damaged by animals in two different ways. The pericarp, in addition to the seed coat surrounding parenchyma seed contents, is suggestive of an angiospermous affinity, as such a 3+3 structure is distinct from a three-layered seed coat in gymnosperms. The seed possesses a distal micropyle, attached on the base of the pericarp, suggestive of a former orthotropous ovule in the gynoecium. The damaged pericarp of Jurafructus suggests that frugivory can be dated back to the Middle–Late Jurassic. Apparently, the ecological relationship between angiosperms and animals extends deep into the fossil record.  相似文献   
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辽宁北票鸟化石群国家级自然保护区,地层主要包括金岭寺群上部土城子组和热河群下部义县组。保护区鸟类化石群保存完好,仅“核心区”2km2就共采出鸟化石约800枚,已鉴定出6属8种,创下了古鸟类研究史上鸟化石数量最多、鸟化石层位最多、埋藏密度最大的纪录,同时它们与7门18纲27类化石共存。保护区的鸟类化石、被子植物化石对其起源和早期演化等研究具有重要意义。建议国家有关方面向联合国教科文组织申报辽宁北票鸟化石群国家级自然保护区为世界文化遗产或重要科学遗址。  相似文献   
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本文研究了我国湖北省武汉市新洲县阳逻镇北部发掘的硅化木,它们是武汉杜英(Elaeocarpuswuhanen-sisJ.J.Yangsp.nov.)、武汉猫尾木(DolichandronewuhanensisJ.J.Yangsp.nov.)湖北石梓(GmelianahubeiensisJ.J.Yangsp.nov.)。这些硅化木的地质年代为晚第三纪。硅化木的发掘反映了当时当地的气候比较炎热和潮湿。从树种方面为长江流域新生代的地质、古地理、古生物群演变研究,提供了新的科学证据。  相似文献   
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The angiosperm pollen record from the Anfiteatro de Ticó and Punta del Barco formations (Baqueró Group) is reported. The relevance of these floras is that they are accurately dated as late Aptian, and one of the oldest floras southern South America with fossil angiosperms. Twelve samples were studied, showing Clavatipollenites and Retimonocolpites as dominant types. A new species, Jushingipollis ticoensis sp. nov., is proposed. A doubtful angiosperm pollen grain, Lethomasites sp., is also identified and described. A multivariate analysis of similarities between different Early Cretaceous angiosperm pollen assemblages suggests that the Baqueró Group assemblages have great similarities with other coeval units from Argentina, Australia and United States, which were located in a similar paleolatitude.  相似文献   
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