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11.
黄山松母树林基地松斑螟的生物学特性及发生规律   总被引:2,自引:0,他引:2  
松斑螟是危害黄山松梢头和球果的主要害虫。该虫 1年 2代 ,4~ 10月为危害盛期 ,5、6月和 8、9月为危害高峰期。本文主要探讨了该虫的生物学特性和发生规律。  相似文献   
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The German paleontologist H. G. Bronn is best remembered for his 1860 translation and critique of Darwin’s Origin of Species, and for supposedly twisting Darwinian evolution into conformity with German idealistic morphology. This analysis of Bronn’s writings shows, however, that far from being mired in an outmoded idealism that confined organic change to predetermined developmental pathways, Bronn had worked throughout the 1840s and 1850s on a new, historical approach to life. He had been moving from the study of plant and animal forms in the abstract towards placing them into geological and biogeographical context, analyzing patterns of progress and adaptation, explaining species diversity and individual variation, and applying biological insights to practical problems such as artificial breeding. Even though Bronn never fully accepted the idea of species transformation, he saw Darwin’s theory as a bold new move toward his own goal of establishing a comprehensive, historical science of life, and he presented it as such in his translation and commentary. Thus Darwin’s ideas gained a quick and generally favorable hearing in Germany not because of their easy assimilability into an older tradition, but because of their appeal to the innovative Bronn.  相似文献   
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《L'Anthropologie》2023,127(2):103135
The discovery of Pleistocene human presence at Chiquihuite Cave (state of Zacatecas, Mexico) dating to, or even before, the Last Glacial Maximum (LGM, over 18,000 years ago), prompted the search for another cave site in the same region, where the implications of Chiquihuite could be tested and corroborated in a second context. In January 2020, we started work at Sima de las Golondrinas (“Chasm of Swallows”), a cavern in the Zuloaga mountains. Excavation unit X-20 focused on an older profile left behind by unknown early-20th-century explorers. Previous radiocarbon dating of three charcoal-rich deposits had indicated the stratigraphy contained deposits ranging in age from the Terminal LGM to the Middle Holocene. The short-timed excavation revealed the stratigraphic sequence had been slowly deposited in an aquatic environment, when the cave was partly inundated for thousands of years, until the Holocene. Preliminary palynological studies confirmed the presence of water and nearby lakes, matching the paleoenvironmental reconstructions from Chiquihuite, 100 km away. Excavation X-20 yielded no lithic tools or stone raw materials, but an abundance of zoo-archaeological materials, yet without the presence of traditional megafauna. Some specimens present human modifications in the form of butchery-related cut marks, but also engravings possibly related to early symbolic behaviors. Here, we present a selection of eight bones of elevated archaeological importance. One of them is an ischium bone belonging to a young Homo sp. individual, dating to the Early Holocene. The other seven are modified bones coming from layers dating between the Terminal LGM and Younger Dryas. They belonged to white-tailed deer (Odocoileus virginianus), mountain bighorn sheep (Ovis canadensis), and American pronghorn (Antilocapra americana). The assemblage includes four human-modified animal phalanges, with symbolic expression substrates. Two of them were found in levels older than 16,000 years, and may well represent some of the oldest forms of art in the Americas.  相似文献   
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