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71.
JAMES F. HARWOOD KEHUI CHEN HANS‐GEORG MÜLLER JANE‐LING WANG ROGER I. VARGAS JAMES R. CAREY 《Physiological Entomology》2013,38(1):81-88
The reproductive ability of female tephritids can be limited and prevented by denying access to host plants and restricting the dietary precursors of vitellogenesis. The mechanisms underlying the delayed egg production in each case are initiated by different physiological processes that are anticipated to have dissimilar effects on lifespan and reproductive ability later in life. The egg‐laying abilities of laboratory‐reared females of the Mediterranean fruit fly (Ceratitis capitata Wiedmann) and melon fly (Bactrocera cucurbitae Coquillett) from Hawaii are delayed or suppressed by limiting access to host fruits and dietary protein. In each case, this is expected to prevent the loss of lifespan associated with reproduction until protein or hosts are introduced. Two trends are observed in each species: first, access to protein at eclosion leads to a greater probability of survival and a higher reproductive ability than if it is delayed and, second, delayed host access reduces lifetime reproductive ability without improving life expectancy. When host access and protein availability are delayed, the rate of reproductive senescence is reduced in the medfly, whereas the rate of reproductive senescence is generally increased in the melon fly. Overall, delaying reproduction lowers the fitness of females by constraining their fecundity for the remainder of the lifespan without extending the lifespan. © 2013 The Royal Entomological Society 相似文献
72.
Franz Th. FÜrsich 《Pal?ontologische Zeitschrift》1980,54(3-4):289-300
The observed life positions of 23 species of Jurassic bivalves are recorded and compared to reconstructions derived from functional interpretations of their morphology and comparisons with Recent relatives. In the majority of cases, these inferences correspond with field observations. There are, however, cases such ashognomon where likely reconstructions differ. These could easily lead to an erroneous interpretation of the autecology of some species. 相似文献
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ABSTRACT Seasonal changes of parameters of full song were studied in a free-living population of chaffinches Fringilla coelebs during one entire reproductive period. Approximately 7000 strophes sung by 14 male chaffinches were recorded and analysed by sonography and a particular oscillographic method. While the general pattern of song strophes, i.e. characteristics of elements, number and arrangement of phrases, and final flourish, remained constant throughout the reproductive period, full song varied with respect to the repetition rate of strophes, number of strophe types used, intensity of singing, duration of strophes, and percentage of incomplete strophes sung. These changes are discussed as results of learning processes, social interactions in the population, and endogenous mechanisms activating memorized information. 相似文献
76.
First record of red cornetfish Fistularia petimba (Syngnathiformes:Fistulariidae) from Antalya and İskenderun Bays along Turkish Coasts of the Mediterranean Sea 下载免费PDF全文
A. Ünlüoğlu S. Akalın İ. Dal E. M. Tıraşın C. M. Aydın 《Zeitschrift fur angewandte Ichthyologie》2018,34(4):977-980
Here, we report the first occurrence of red cornetfish Fistularia petimba in the north‐eastern Mediterranean Sea. Altogether four specimens were captured; first two in Antalya Bay on 28 October 2016 and 26 November 2016, and the remaining two in ?skenderun Bay on 21 May 2017 during the bottom trawl surveys along the Mediterranean coast of Turkey. All specimens were young and more or less uniform in size (383, 335, 419 and 453 mm standard length). The possibility that F. petimba could become a new potential invader in the Mediterranean as its congeneric F. commersonii is cautioned against. 相似文献
77.
Derya Ürkmez Marta Ostrowska Milena Roszkowska Magdalena Gawlak Krzysztof Zawierucha Reinhardt Møbjerg Kristensen 《Marine Biology Research》2018,14(1):1-16
In this paper, Megastygarctides sezginii sp. nov., a new marine species from the Black Sea (Turkey), is described. Morphological and morphometric studies have revealed that M. sezginii sp. nov. is most similar to M. setoloso Morgan & O’Reilly, 1988, but differs from it through the presence of two types of fibrils, a lack of cuticle granulation, the presence of three lateral projections with fibrils, leg fibrils arranged in transverse stripes and the presence of clumps of fibrils near the clavae. In the studied environment, the new species is frequently found in summer and almost absent in winter. Additionally, a taxonomic key for all Megastygarctides species is presented.
http://zoobank.org/urn:lsid:zoobank.org:pub:53AA1D57-8700-4A18-9099-1CDDBAEB4D3A 相似文献
78.
Methylparaben induces malformations and alterations on apoptosis,oxidant–antioxidant status,ccnd1 and myca expressions in zebrafish embryos 下载免费PDF全文
Perihan Seda Ateş İsmail Ünal Ünsal Veli Üstündağ Ahmet Ata Alturfan Türkan Yiğitbaşı Ebru Emekli‐Alturfan 《Journal of biochemical and molecular toxicology》2018,32(3)
Methylparabens (MP) are widely used as preservatives in cosmetics, pharmacy, and food industry. Although acute toxicity studies in animals indicated that parabens are not significantly toxic, the effects of chronic exposure under sublethal doses are still unknown and the number of related studies is limited. Our aim was to evaluate the effects of MP on the development of zebrafish embryos focusing on development, locomotor activity, oxidant–antioxidant status, apoptosis, and ccnd1 and myca expressions. The expressions of ccnd1 and myca were determined by RT‐PCR. Lipid peroxidation (LPO), nitric oxide (NO), and glutathione‐S‐transferase (GST) activities were determined spectrophotometrically. Apoptosis was determined using acridine orange staining. Locomotor activity was measured using touch‐evoked movement test. MP exposure increased malformations, LPO, apoptosis, ccnd1 and myca expressions, and decreased GST activities and NO levels compared with the control group. Our findings will lead to further understanding of the mechanism of MP toxicity, and merit further research. 相似文献
79.
CYCLIC adenosine-3′,5′-monophosphate (cyclic AMP) acts as a chemotactic factor causing cell aggregation in the slime mould, Dtctyosteltum discoideum1,2. Aggregation in this organism is the link between the growth phase and the second phase of development, in which cells cooperate and differentiate to form a multicellular fruiting body. The finding that cyclic AMP also mediates developmental functions other than chemotaxis3 suggests that regulation of cyclic AMP synthesis and destruction is important in the control of morphogenesis in D. discoideum. 相似文献
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