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51.
Recently, biologist and philosophers have been much attracted by an evolutionary view of knowledge, so-called evolutionary epistemology. Developing this insight, the present paper argues that our cognitive abilities are the outcome of organic evolution, and that, conversely, evolution itself may be described as a cognition process. Furthermore, it is argued that the key to an adequate evolutionary epistemology lies in a system-theoretical approach to evolution which grows from, but goes beyond, Darwin's theory of natural selection.  相似文献   
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Data from eight published studies were combined to show that the influence of traffic density on Pb contents in roadside soils increases with proximity to the road.  相似文献   
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Chromosome numbers were determined for 86 Anthurium species. Fifty-one of these were newly determined with counts ranging from 2n = 24 to 66 and 30 being the most common. All known Anthurium chromosome numbers were summarized, and 43 taxonomic changes were made in the previous reports to reflect current taxonomy. In terms of somatic chromosome numbers, the numbers form four polyploid series of 20–40–60, 24–30–48–84, 28–56 and 30–60–90–ca. 124. Paleoaneuploidy, polyploidy and B-chromosomes are basic features of the genus, but subsequent recent aneuploidy is not. The exact nature of chromosome evolution in Anthurium remains to be elucidated.  相似文献   
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The histologic properties of pleural adipose organs were studied in 14 newborns. These organs contain milky spots, in which lymphocytes, macrophages and plurivacuolated fat cells are present. The milky spots have a mesothelial covering, persist to the age of 9 months and seem to act as defence devices and a site of fluid exchange.  相似文献   
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The starling cochlea was studied with TEM at four locations along the basilar papilla to investigate gradients in morphological features over the papilla's length and width. Hair cell shape changes continuously from neural to abneural and from basal to apical. Unlike the situation in mammals, there are no distinct populations of hair cells; the previously described types (tall hair cells and short hair cells) are merely extremes in a continuum. Contacts between THC are a normal feature. Except at the base of the papilla, SHC have very large cuticular plates, suggesting a micromechanical function for these cells. In contrast to the THC, the SHC normally completely lack afferent innervation; this indicates that their function is restricted to within the basilar papilla itself. © 1992 Wiley-Liss, Inc.  相似文献   
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