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The south-eastern islands of Indonesia between Bali in the west and Timor in the east define a region that is at the interface of the Asian and Australasian biogeographic regions. Three subspecies of the colubrid snake Dendrelaphis pictus have previously been recognized from the region: Dendrelaphis pictus pictus (Bali and Lombok); D. p. inornatus (Sumba to Timor); and D. p. intermedius (Sumbawa to Alor). A re-examination of Dendrelaphis pictus in this region uses multivariate statistics to examine the geographic variation in head-shield and body measurements within the species. The findings re-interpret the taxonomy, indicating that D. pictus from Bali and Lombok are specifically different from D. inornatus on the remaining islands on the Banda Arc. The populations of D. inornatus on the islands of Sumbawa, Sumba, Sawu, Flores, and Lembata are subspecifically different from those on Roti, Semau, Timor, Alor, and Wetar.
Several head-shield measures are strongly correlated with longitude within D. inornatus , suggesting environmentally triggered selection gradients. However, for many variables, the two subspecies differ significantly in the direction of the trends which suggests the subspecies respond differently to these environmental gradients. There is evidence that Dendrelaphis individuals may be transported through the islands by anthropogenic agencies. 相似文献
Several head-shield measures are strongly correlated with longitude within D. inornatus , suggesting environmentally triggered selection gradients. However, for many variables, the two subspecies differ significantly in the direction of the trends which suggests the subspecies respond differently to these environmental gradients. There is evidence that Dendrelaphis individuals may be transported through the islands by anthropogenic agencies. 相似文献
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Martin J. How Jan M. Hemmi 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2008,194(12):1053-1061
Male and female animals are not always complicit during reproduction, giving rise to coercion. One example of a system that is assumed to involve sexual coercion is the mate herding behaviour of fiddler crabs: males push females towards the home burrow with the goal of forcing copulation at the burrow entrance. We recorded and analysed in detail the courtship behaviour of a North Australian species of fiddler crab Uca elegans. Courtship was composed of four main phases: broadcast waving, outward run, herding and at burrow display. During interactions males produced claw-waving displays which were directed posteriorly towards the female and which varied in timing and structure depending on the courtship phase. We suggest that courtship herding in U. elegans is driven primarily by mate choice for the following reasons, (1) females can evade herding, (2) no other reproductive strategies were observed, (3) males broadcast their presence and accompany courtship with conspicuous claw waves, and (4) the behaviour ends with the female leading the male into the home burrow. As an alternative function for herding in U. elegans we suggest that the behaviour represents a form of courtship guiding, in which males direct complicit females to the correct home burrow. 相似文献
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High levels of polyandry,but limited evidence for multiple paternity,in wild populations of the western rock lobster (Panulirus cygnus) 下载免费PDF全文
Jacqueline Loo Winn Jason Kennington Simon de Lestang Jason How Jonathan P. Evans 《Ecology and evolution》2018,8(9):4525-4533
Polyandry, where multiple mating by females results in the temporal and spatial overlap of ejaculates from two or more males, is taxonomically widespread and occurs in varying frequencies within and among species. In decapods (crabs, lobsters, crayfish, and prawns), rates of polyandry are likely to be variable, but the extent to which patterns of multiple paternity reflect multiple mating, and thus are shaped by postmating processes that bias fertilization toward one or a subset of mated males, is unclear. Here, we use microsatellite markers to examine the frequency of multiple mating (the presence of spermatophores from two or more males) and patterns of paternity in wild populations of western rock lobster (Panulirus cygnus). Our data confirm that >45% of females had attached spermatophores arising from at least two males (i.e., confirming polyandry), but we found very limited evidence for multiple paternity; among 24 clutches sampled in this study, only two arose from fertilizations by two or more males. Single inferred paternal genotypes accounted for all remaining progeny genotypes in each clutch, including several instances when the mother had been shown to mate with two or more males. These findings highlight the need for further work to understand whether polyandry is adaptive and to uncover the mechanisms underlying postmating paternity biases in this system. 相似文献
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Olivier Lefebvre Wai K. Ooi Zhe Tang Md. Abdullah-Al-Mamun Daniel H.C. Chua How Y. Ng 《Bioresource technology》2009,100(20):4907-4910
Microbial fuel cells (MFCs) are considered as a promising way for the direct extraction of biochemical energy from biomass into electricity. However, scaling up the process for practical applications and mainly for wastewater treatment is an issue because there is a necessity to get rid of unsustainable platinum (Pt) catalyst. In this study, we developed a low-cost cathode for a MFC making use of sputter-deposited cobalt (Co) as the catalyst and different types of cathode architecture were tested in a single-chambered air-cathode MFC. By sputtering the catalyst on the air-side of the cathode, increased contact with ambient oxygen significantly resulted in higher electricity generation. This outcome was different from previous studies using conventionally-coated Pt cathodes, which was due to the different technology used. 相似文献
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Mei Wang Yok Moi Khoo Jin Zhou Patrick Casey How Sung Lee 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(5-6):553-557
Cysmethynil, a newly identified small molecule inhibitor of isoprenylcysteine carboxylmethyl transferase (Icmt) is involved in the post-translational modification of CaaX proteins. Cysmethynil causes cell death in many human cancer cells in vitro, and inhibits tumor growth in the xenograft mouse model in vivo. A HPLC method for the quantification of cysmethynil in mouse plasma was developed and validated. The lower limit of quantification of this method was 0.01 μg/ml. Inter- and intra-day variability ranged from 0.38–8.5% and accuracy was between 86% and 98%. This sensitive method was used to quantify cysmethynil in plasma of mice after intraperitoneal dosing for preliminary pharmacokinetic studies. 相似文献
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Neda Naderali Ganesan Vadamalai Yee How Tan Naghmeh Nejat 《Journal of Phytopathology》2014,162(4):264-268
Yellowing symptoms similar to coconut yellow decline phytoplasma disease were observed on lipstick palms (Cyrtostachys renda) in Selangor state, Malaysia. Typical symptoms were yellowing, light green fronds, gradual collapse of older fronds and decline in growth. Polymerase chain reaction assay was employed to detect phytoplasma in symptomatic lipstick palms. Extracted DNA was amplified from symptomatic lipstick palms by PCR using phytoplasma‐universal primer pair P1/P7 followed by R16F2n/R16R2. Phytoplasma presence was confirmed, and the 1250 bp products were cloned and sequenced. Sequence analysis indicated that the phytoplasmas associated with lipstick yellow frond disease were isolates of ‘Candidatus Phytoplasma asteris’ belonging to the 16SrI group. Virtual RFLP analysis of the resulting profiles revealed that these palm‐infecting phytoplasmas belong to subgroup 16SrI‐B and a possibly new 16SrI‐subgroup. This is the first report of lipstick palm as a new host of aster yellows phytoplasma (16SrI) in Malaysia and worldwide. 相似文献