Studying the reproductive attributes of pests is central to understanding their life cycle history and in crafting management strategies to regulate, if not bring down, their population below threshold levels. In this article, the morphology of the male reproductive tract, topology of the spermatozoa, and salient features of spermiogenesis in the Chinese white pine beetle, Dendroctonus armandi Tsai and Li was studied to provide baseline information for further pest management studies. Results showed that male reproductive tract of this species differs from those documented in other Coleopterans by having 20 testicular tubules in each testis and the presence of two types of accessory glands. The spermatozoon is seen having peculiar characteristics such as an “h”-shaped acrosomal vesicle with a “puff”-like expansion, one centriole, one large spongy body, and two accessory bodies. Despite with some morphological differences of the male reproductive organ, spermatogenesis in this organism is similar to other Coleopterans. Overall, detailed studies regarding the components of the primary male reproductive organ of this beetle species would expand the knowledge on the less-understood biology of Coleopteran pests and would help in designing regulatory measures to conserve endemic and indigenous pine trees in China.
Ore mining is among the most environmentally destructive anthropogenic practices, particularly in developing countries. Correct assessment of its impacts on soil ecosystems requires an understanding of the response of soil food webs. Nematodes, often the most abundant invertebrates in soils, occupy various positions in food webs, and their assemblages are commonly used to reflect soil health. In October 2014, we collected soil samples from five sites of a small-scale mining area in Sibutad, southern Philippines, to assess the influence of mining activities on nematode assemblages. Two sites were considered undisturbed as there were no visible signs of mining, while the other three sites were disturbed. Nematodes were extracted live and identified to genus level using morphology-based identification. We analysed genus composition, genus and trophic diversity, and the life-history based maturity index. We measured soil environmental variables (pH, organic matter, granulometry and several heavy metals), and correlated variation in nematode genus composition to variation in these environmental factors. Small-scale mining activities had variable but generally nonsignificant impacts on soil properties, altered vegetation and caused increases in concentrations of Hg and Pb, but not consistently so in all impacted sites. The high patchiness in vegetation and heavy metal content were reflected in a high within-site variability of nematode assemblages. Total nematode abundance was significantly lower in two mainly physically disturbed sites, but not so in the most metal-polluted one, suggesting that abundance is not a good indicator of pollution status. Nematode genus composition significantly differed between disturbed and undisturbed sites. By contrast, only few differences between sites were found for diversity or maturity indices, demonstrating that genus composition was a better indicator of mining-related effects than many common indicator indices and highlighting that detailed assemblage analysis is required for a correct interpretation of moderate pollution effects on soil 2 nematodes. Measured environmental variables together explained 60% of the variation in nematode assemblages in the area; the three 'single best' explanatory variables were the concentrations of Pb, Hg and N, but none of these by itself explained more than 8% of the variation in nematode data, while their combination explained 24%. Some genera of predacious and omnivorous nematodes, which are generally expected to be sensitive to both chemical pollution and physical disturbance (e.g., Ironus and Eudorylaimus), were most abundant in sites with elevated heavy metal concentrations, which can have repercussions for the interpretation of nematode-based indices such as the MI.
Scales have numerous hidden details in their sculptural design that contributes effectively to fish identification and classification. A traditional approach has been made to study the scale morphology of the yellow striped goatfish Upeneus vittatus (Forskål, 1775) using a micron cam attached to a Gateway computer and a stereomicroscope in tandem with a 14 megapixel Kodak easyshare Z 1485 IS digital camera in which digitized images were processed using Corel Paint Photoshop 2x program.To eliminate subjective human error, scale variation in scale images were subjected to Elliptic Fourier Analysis using 77 Fourier descriptors and Principal Component Analysis to discriminate variation between scale shapes within the male and female U. vittatus and to use the data generated to established variation between male and female species.Scanned images (1200dpi) were binarized to generate chain codes using SHAPE 1.3 version. The data were analyzed using Principal Component Analysis conducted using the PAST software ver. 1.8.Result of the study revealed that there is a high significance in the variation of shapes within male and female individuals of U. vittatus and that a significant variation in scale shapes was observed between male and female species.This study demonstrated that scale characteristics can provide useful taxonomic information on the morphological differences between sexes of U. vittatus and that elliptic Fourier analysis and principal Component analysis are good tools to discriminate variation in scale shapes.
As individuals and political leaders increasingly interact in online social networks, it is important to understand how the affordances of social media shape social knowledge of morality and politics. Here, we propose that social media users overperceive levels of moral outrage felt by individuals and groups, inflating beliefs about intergroup hostility. Utilizing a Twitter field survey, we measured authors’ moral outrage in real time and compared authors’ reports to observers’ judgments of the authors’ moral outrage. We find that observers systematically overperceive moral outrage in authors, inferring more intense moral outrage experiences from messages than the authors of those messages actually reported. This effect was stronger in participants who spent more time on social media to learn about politics. Pre-registered confirmatory behavioral experiments found that overperception of individuals’ moral outrage causes overperception of collective moral outrage and inflates beliefs about hostile communication norms, group affective polarization and ideological extremity. Together, these results highlight how individual-level overperceptions of online moral outrage produce collective overperceptions that have the potential to warp our social knowledge of moral and political attitudes.
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