分类： 心理学 >> 发展心理学 提交时间： 2021-07-21
摘要： 个体学习符号分数的一个关键是能对其数值形成准确表征。现有研究假设符号分数表征的认知基础是人类自婴幼儿期就具有的非符号数量表征（如表征两个集合各自的数量，或两个数量的比例）。其证据包括表征非符号数量(尤其是非符号数量比例关系)和表征符号分数在行为和大脑神经活动层面上都表现出相关性。然而要说明非符号数量表征是符号分数表征的认知基础，还需更多研究表明两者在数量概念上的独特相关和因果联系，并阐明符号分数表征形成的认知机制。
分类： 生物学 >> 动物学 提交时间： 2021-07-21 合作期刊: 《古脊椎动物学报》
摘要： Abundant mammalian fossils were uncovered during the field exploration for Nihewan beds at the beginning of the 1980s along Xinyaozi Ravine at Nangaoya Township of Tianzhen County, Shanxi Province in North China and the studied taxa indicate an age of the early Early Pleistocene. Recent studies on the rhino material not yet described show that there are at least two species of rhinocerotids: Elasmotherium peii and Coelodonta nihowanensis. There might be a third taxon provisionally named as Stephanorhinus cf. S. kirchbergensis due to incompleteness of the specimens. Since its morphometric characters are between S. kirchbergensis and C. nihowanensis, it might be a variety of one of the two species although it is more similar to the former than the latter. In the same way, The rhino specimens from Xiashagou named as Rhinoceros sinensis (?) by Teilhard de Chardin and Piveteau (1930) might be a variety of S. kirchbergensis or C. nihowanensis. The rhinocerotids uncovered so far from the Early Pleistocene deposits in the generalized Nihewan Basin including two certain species and two uncertain ones. The localities yielding E. peii include Xiashagou, Shanshenmiaozhui, Daheigou and Xinyaozi; those yielding C. nihowanensis include Xiashagou, Danangou, Donggutuo, Shanshenmiaozhui and Xinyaozi. R. sinensis (?) appeared only at Xiashagou and Stephanorhinus cf. S. kirchbergensis only at Xinyaozi.
分类： 生物学 >> 动物学 提交时间： 2021-07-21 合作期刊: 《古脊椎动物学报》
摘要： Robust regional chronostratigraphic framework is the basis of understanding climatic and faunal events in the geologic history. One of the most dramatic faunal turnovers of the past 50 million years in Asia is linked to the Eocene–Oligocene Transition (EOT) at about 34 Ma. However, the chronostratigraphic relationships between faunal modulation and geologic events associated with the EOT in China have remained uncertain before and after the epoch boundaries, mainly due to the scarcity of continuous records and problems in correlating and subdividing the classic areas containing abundant mammalian fossils. Past decades have seen developments in establishing Chinese regional Paleogene Land Mammal Ages, and albeit many ages are well constrained, some, such as those of the latest Eocene and the Oligocene, have remained unsettled. In this paper, we present how recent evidence from the fossiliferous Ulantatal sequence, Nei Mongol, China, provides better constraints to the latest Eocene and Oligocene Chinese Land Mammal ages (Baiyinian, Ulantatalian, and Tabenbulukian). We propose Ulantatal sequence as a new regional unit stratotype section of the Ulantatalian stage, and the lower boundary of Tabenbulukian stage to be reassigned to Chron C9r (27.7 Ma), with the lowest occurrence of Sinolagomys as the marker horizon.
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