An experimental analysis of mate choice in the wren: a monomorphic, polygynous passerine

Male wrens (Troglodytes troglodytes) construct nests that areused in their display to females. Previous work has suggestedthat the number of vacant nests may be used as a mate choicecue. Correlational data from 1992 confirmed that females appearedto be assessing die number of vacant nests on a male's territoryand preferentially mating with males with more nests. Male taillengdi was also correlated widi mating success. In 1993 thenumbers of nests on territories was experimentally manipulated,the female setdement patterns confirmed that die number of vacantnests did mediate mate choice. Male tail length failed to explainadditional variance in mating success when die variance explainedby the experimental manipulation was removed, suggesting diatdie original correlation arose because both tail length andmating success were correlated widi a confounding variable.The structure of the vegetation in a male's territory influencedmating success. This appeared to be due to nests surviving betterin territories widi dense vegetation. Males on territories inwhich nests survive well had longer tails. Male-male competitionfor good territories may explain die observed effects of malemorphology on mating success. Furdier analysis of die nest choicedata showed diat all nests had an equal chance of being usedby a female. The fact diat all nests had an equal probabilityof being chosen by a female means diat each additional nestbuilt by a male wren results in die same increase in matingsuccess. This suggests diat die benefits to males of nest buildingincrease linearly. The number of nests on a territory will beaffected by various factors such as predation pressure, nestbuilding rate, and vegetation structure. The information diatfemales are getting by assessing such a signal is discussed.     

不同光学异构体组成的氯氰菊酯对敏感及抗性家蝇的神经电生理学研究

采用敏感家蝇(Musca domestica vicina L.)及由5种不同光学异构体组成的氯氰菊酯选育的抗性家蝇中胸足离体标本,观测五种药剂对足感觉神经纤维冲动发放的影响。各种异构体组成的氯氰菊酯均可引起感觉神经纤维发放的增加,然后逐渐降低,直至完全阻断。以阻断时间和加药剂量为参数,求出神经敏感度。结果表明：五种药剂作用于敏感家蝇的神经敏感度与室内生物测定的LD₅₀值(μg/头)无相关性,而与供试药剂中反α体与顺α体的比例有关,反α体所占比例越多的药物,神经敏感度越高。抗性家蝇的神经敏感度与敏感 家蝇相比大幅度下降,可以认为神经敏感度降低是家蝇对氯氰菊酯产生抗性的主要机制。抗性家蝇中,氯氰菊酯品系(RC₁)的抗生水平最高,但它的神经敏感度较其它抗性品系也高,由此推测,RC₁,的抗性机制与其它晶系有所不同。     

Separation of multiple forms of acidic glutathione S-transferase isozymes in a susceptible and a resistant strain of house fly,Musca domestica (L.)

The acidic glutathione S-transferases from a CSMA (susceptible) strain and a Cornell-R (resistant) strain of houseflies were purified and separated utilizing affinity chromatography followed by chromatofocusing. Nine fractions were isolated from each house fly strain. Fraction 1 had the highest 1-chloro-2,4-dinitrobenzene vs. 1,2-dichloro-4-nitrobenzene ratio (CDNB/DCNB ratio) in both strains and the ratio of all the other fractions tended to decrease as the isoelectrical points decreased except for fractions 4 and 9. Most fractions from the CSMA strain had higher CDNB conjugation activities than the fractions from the Cornell-R strain, but all the fractions from the CSMA strain had lower DCNB conjugation activities than fractions from the Cornell-R strain. Steady-state kinetics of all the fractions were examined. The Km values obtained from both strains ranged from 0.36 to 1.12 mM, while the Vmax value ranged from 3.0 to 32.6 μmol/min/mg. In the 100,000 g supernatant, the CDNB specific activities in the CSMA strain was about 1/3 of the activity in the Cornell-R strain but it was about 1.5-fold following affinity chromatography. The specific activity for DCNB measured in the CSMA strain was only 1/5 of the activities of the Cornell-R strain in the 100,000 g supernatant, but was about the same after affinity chromatography. The difference was due to the selectivity of the affinity column used in the current study. © 1995 Wiley-Liss, Inc.     

Sex ratios of Spalangia endius (Hymenoptera: Pteromalidae), in relation to current theory

Abstract. 1. Spulungiu endius Walker is a solitary parasitoid of house fly puparia.
2. The sex and size of S.endius was not related to host size.
3. In the laboratory the mean sex ratio of all offspring of nine groups, each comprising twenty females, was consistently female-biased (x = 83.5%, range 79–87%). The sex ratio in the field was less female-biased and showed greater fluctuation (61–75%). This may be a consequence of females laying male eggs before mating, some females remaining unmated, possible shorter adult life expectancy in the field than in the laboratory, and, perhaps, the presence of conspecific females.
4. The sex ratio of offspring of individual females varied from 66% to 100% females, and males were deposited early in the oviposition sequence.
5. Although a large number of fly puparia died before adult flies or parasitoids emerged (64.5%; n = 5874), there was no differential mortality of either sex.
6. Our results fit no general sex ratio hypothesis and we conclude that (i) the genetic nature of sex ratios in these insects needs careful examination, and (ii) the prevalence of female-biased sex ratios in solitary parasitoids needs investigation.     

Linkage of Pgm-3 in the house mouse and homologies of three phosphoglucomutase loci in mouse and man

The discovery of a third phosphoglucomutase locus (Pgm-3) in the house mouse is reported. Three alleles are recognized on the basis of differences in electrophoretic mobility and enzymatic activity. Pgm-3 ^a (fast mobility and high activity) is present in inbred strain C57BL/10J and 24 other strains; Pgm-3 ^b (slow mobility and high activity) is present in LP/Pas and six other strains; and Pgm-3 ^c (no detectable activity in any tissue tested) is present in strain DBA/2J and 14 other strains. Seventy-four recombinant inbred strains derived from progenitors that differed at Pgm-3 were used to study genic linkage. Pgm-3 is on chromosome 9 and is linked to Sep-1, d, Mod-1, and Ltw-3. Gene order and recombination frequencies are estimated as d 3.8±1.8% Pgm-3 2.3±1.2% Mod-1. Substrate specificities and cofactor requirements show that mouse Pgm-1 is homologous with human Pgm-2, mouse Pgm-2 with human Pgm-1, and mouse Pgm-3 with human Pgm-3.This research was supported in part by NIH Research Grant GM18684 from the National Institute of General Medical Sciences to B.A.T. and by grants from NIH A105531-02 and the Volkswagon Foundation to Jan Klein. J.H.N. was a recipient of a Fellowship from the Max-Planck-Gesellschaft, Munich. G.S. and J.K. were supported by funds from the Deutsche Forschungsgemeinschaft.     

Characterization of Polar and Non‐Polar Compounds of House Edible Bird's Nest (EBN) from Johor,Malaysia

This work investigated the polar (PC: protein, amino acid and metabolite) and non‐polar (NPC: fatty acid) compounds and bioactivity characteristics of the EBN harvested from the state of Johor in Malaysia. The electrophoretic gels exhibited 15 protein bands (16–173 kD) with unique protein profile. Amino acids analysis by AccQ?Tag method revealed 18 types of amino acids in EBN. Metabolite profiling was performed using High‐Performance Liquid Chromatography coupled with Quadrupole Time‐of‐Flight Mass Spectrometer (HPLC‐QTOF/MS) technique and a total of 54 compounds belonging to different groups were detected and identified. These findings help to uncover the relation of therapeutic activity of EBN. The EBN was further extracted with AcOEt and BuOH. The AcOEt extract was fractionated into three fractions (F₁?F₃), and the high triglyceride content in F₂ was verified by gC‐FID. The three groups of fatty acids discovered in EBN are 48.43 % of poly‐unsaturated (PUFA), 25.35 % of saturated fatty acids (SFA) and 24.74 % of mono‐unsaturated fat (MUFA). This is the first time to report results ofEBN, BuOH, and AcOEt extracts and of fraction F₂ (TEBN) on their analysis for their antioxidant activities by DPPH, ABTS and catalase assay and for their paraoxonase and anti‐tyrosinase activities. The results showed that TEBN exhibited the significant bioactivity in all assays. These findings suggest that TEBN is a good source for natural bioactive compounds in promoting body vigor. Current work widened the content of EBN especially on the triglyceride and also marked the content of specific location (Johor, Malaysia) of EBN origin.     

Evidence of repertoire sharing and stability despite a high turnover rate in a duetting neotropical wren

In songbirds, the spatial pattern of song sharing among individuals is influenced by the song learning and dispersal strategies within each species. In birds where females and males sing and create joint acoustic displays (duets), the processes defining the patterns of song sharing become more complex as there might be different selection pressures shaping the behaviour of each sex. To provide further insight into the vocal development and the dispersal strategy of duetting tropical species, we investigated the patterns of individual and pair repertoire sharing, as well as the stability of these repertoires, in a colour-marked population of riverside wrens, Cantorchilus semibadius, located in the Osa Peninsula, Costa Rica. Using data collected over a five-year period, we found considerable variation in the sharing levels of phrase and duet type repertoires among neighbouring individuals coupled with a general decline of repertoire sharing as distance increased between birds’ territories. These results are consistent with a pattern predicted in age-restricted learners that establish preferentially near their tutors. Furthermore, we found no evidence of individuals changing their phrase type repertoires over time, including after remating events. Duet type repertoires were also stable when pairs remained together. However, we observed a surprisingly high turnover rate. When individuals remated, even though the majority of the previous duet type repertoire remained, several new duet types were included. Taken together, our findings suggest that riverside wrens might create their individual repertoires by copying their same-sex parent and neighbouring individuals before dispersal. Additionally, we speculate that even though birds were able to create new duet types after changing partners, a substantial portion of their duet type repertoire might also be copied from their parents and neighbouring pairs during the initial critical period of song learning.     

When genes go wild: highly variable internal transcibed spacer1 and conserved mitochondrial DNA haplotypes used to examine the genetic diversity and dispersal pathways of invasive Hylotrupes bajulus in Western Australia

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