Preferences of female American goldfinches (Carduelis tristis) for natural and artificial male traits

We conducted two experiments to determine mating preferencesof female American goldfinches (Carduelis tristis). In the firstexperiment, females were allowed to choose among four naturallyvarying males. In the second, females chose among four maleswearing either orange, blue, yellow, or no color bands. In experiment1, females performed more courtship with males that had significantlybrighter bills and were brighter overall. In experiment 2, femalespreferred males wearing orange bands over unhanded males. Blue-bandedmales ranked second and yellow third, but neither was preferredsignificantly more often than the unbanded males. A female'spreference for a particular band color was weakly associatedwith her own bill and plumage measures; females with brighterthroat feathers and yellower bills preferred orange bands toblue bands. The results suggest that female preferences fororange and yellow may be functional and that females may alsohave aesthetic preferences.     

The influence of carotenoid acquisition and utilization on the maintenance of species-typical plumage pigmentation in male American goldfinches (Carduelis tristis) and northern cardinals (Cardinalis cardinalis).

Birds display a tremendous variety of carotenoid-based colors in their plumage, but the mechanisms underlying interspecific variability in carotenoid pigmentation remain poorly understood. Because vertebrates cannot synthesize carotenoids de novo, access to pigments in the diet is one proximate factor that may shape species differences in carotenoid-based plumage coloration. However, some birds metabolize ingested carotenoids and deposit pigments that differ in color from their dietary precursors, indicating that metabolic capabilities may also contribute to the diversity of plumage colors we see in nature. In this study, we investigated how the acquisition and utilization of carotenoids influence the maintenance of species-typical plumage pigmentation in male American goldfinches (Carduelis tristis) and northern cardinals (Cardinalis cardinalis). We supplemented the diet of captive goldfinches with red carotenoids to determine whether males, which are typically yellow in color, were capable of growing red plumage. We also deprived cardinals of red dietary pigments to determine whether they could manufacture red carotenoids from yellow precursors to grow species-typical red plumage. We found that American goldfinches were able to deposit novel pigments in their plumage and develop a striking orange appearance. Thus, dietary access to pigments plays a role in determining the degree to which goldfinches express carotenoid-based plumage coloration. We also found that northern cardinals grew pale red feathers in the absence of red dietary pigments, indicating that their ability to metabolize yellow carotenoids in the diet contributes to the bright red plumage that they display.     

Carotenoid-based ornaments of female and male American goldfinches (Spinus tristis) show sex-specific correlations with immune function and metabolic rate

Conspicuous ornamentation has been linked to immunological and physiological condition in males of many species. In species where both sexes are ornamented, it is unclear whether the signal content of ornaments differs between males and females. We examined the immunological and physiological correlates of carotenoid-based bill and plumage ornamentation in American goldfinches Spinus tristis, a species in which bright orange bills are sexually monomorphic but yellow plumage is sexually dimorphic during the breeding season. Because bill color is dynamic over short periods while plumage color is static over longer time frames, we tested whether these signals have the potential to provide temporal information about immunity and condition. In both sexes, bill color (but not plumage color) was negatively related to leukocyte differential, a measure of recent stress, while plumage color (but not bill color) was positively related to resting metabolic rate. In females, bill color also positively correlated with immunoglobulin Y, a component of acquired immunity, while plumage color positively predicted natural antibody levels, a component of innate immunity. In males, neither bill color nor plumage color predicted immune function, suggesting that the mechanisms underlying these signals vary with sex. Our results demonstrate that dynamic signals such as bill coloration do not merely reflect the same information provided by static signals but that these two classes of signal provide information about different temporal aspects of phenotypic quality. Furthermore, our results indicate that a signal expressed in both sexes has the potential to provide different information depending on the sex of the bearer.     

Polymorphic microsatellite loci from the American goldfinch (Carduelis tristis) and their cross‐amplification in a variety of passerine species

Cardueline finches have become important models in studies of sexual selection. Here I describe eight polymorphic microsatellite loci isolated from the American goldfinch (Carduelis tristis) that are useful in parentage and heterozygosity studies. The number of alleles per locus ranged from eight to 38 based on 252 goldfinches. The markers are polymorphic in at least four other Cardueline finch species, and several amplify in nonfinch passerines including red‐winged blackbird (Agelaius phoeniceus), black‐throated blue warbler (Dendroica caerulescens) and tufted titmouse (Baeolophus bicolor), indicating they should be useful in paternity and population studies of a variety of species.     

Plant Finding and Acceptance Behaviors of Anasa tristis (DeGeer)

Finding and acceptance behaviors of Anasa tristis were investigated using plants that are suitable (pumpkin) or unsuitable (cucumber, coleus) for development. A. tristis found plants in the absence of non-contact cues. Plant finding is enhanced by olfaction and vision. A. tristis found suitable and unsuitable plants equally well. The importance of olfaction in plant acceptance is suggested by intense antennation while on plant and change in behavior on pumpkin and coleus after removal of antennae. Insects on suitable and unsuitable plants dab the surface, contact the plant surface with the labium and insert stylets. Post ingestive effects are important for plant acceptance and rejection. Ingesting water and some nutrients from plants unsuitable for development can be important in extending the time available to move between resource patches.     

Experimental infection of American winter flounder (Pseudopleuronectes americanus) with Glugea stephani (Microsporida)

Young-of-the-year Pseudopleuronectes americanus were captured in Sandy Hook Bay, New Jersey and maintained in aquaria at 16–19° C for 115 days in 1982 and 127 days in 1983. Half of them were experimentally exposed to Glugea stephani and the others were sham exposed. During the course of these experiments fish from both groups died as a result of G. stephani infection, demonstrating Glwgea -induced mortality in this species. Infections were found in both control and experimentally exposed fish. Mortality of Glwgea -infected fish in the exposed group was 63% while that in the controls was 28.5%.     

Watermelon seedling growth and mortality as affected by Anasa tristis (Heteroptera: Coreidae)

Adult squash bugs, Anasa tristis (De Geer), were confined on seedling watermelon plants at densities of zero, one, two, and four per plant. Squash bugs were allowed to feed on the plants until plants died or reached 30 cm in height. Number of leaves and length of plant vine were recorded at 2- or 3-d intervals. Seedling foliage, stems, and roots were harvested and dried after plants reached 30 cm in height. Growth of seedlings was regressed on number of squash bugs and results indicated that an increasing density of squash bugs feeding on seedlings resulted in a significant reduction in plant growth. Additionally, increased density of squash bugs resulted in reduced weight of foliage and root dry biomass. Seedling mortality increased as the density of squash bugs increased.     

Male mate choice in the chameleon grasshopper (Kosciuscola tristis)

In many species, males can increase their fitness by mating with the highest quality females. Female quality can be indicated by cues, such as body size, age and mating status. In the alpine grasshopper Kosciuscola tristis, males can be found riding on subadult females early in the season, and as the season progresses, males engage in fights over ovipositing females. These observations suggest that males may be competing for females that are either unmated (early season) or sperm‐depleted (late season). We thus hypothesised that male K. tristis may be choosy in relation to female mating status, and specifically, we predicted that males prefer females that are unmated. We conducted behavioural experiments in which males were given the choice of two females, one mated and one unmated. Contrary to our prediction, males did not mate preferentially with unmated females. However, copulation duration with unmated females was, on average, 24 times the length of copulation with mated females. While female K. tristis can reject mates, we did not observe any evidence of overt female choice during our trials. Females may gain additional benefits from mating multiply and may therefore not readily reject males. While our experiment cannot definitively disentangle female from male control over copulation duration, we suggest that males choose to invest more time in copula with unmated females, perhaps for paternity assurance, and that male mate assessment occurs during copulation rather than beforehand.     

Monitoring wild greenfinch (Carduelis chloris) for Salmonella enterica typhimurium

The identification and monitoring of emerging infectious diseases in free living wild birds is a challenge to wildlife biologists. In this study, a non-invasive methodology for identifying salmonellosis in wild garden birds was developed. We focussed on greenfinch, Carduelis chloris, which were found to have a seasonal pattern in the occurrence of Salmonella Typhimurium DT 56(v). Principal components analysis of biometric data indicated that low fat and low weight could be useful indicators of Salmonella positive greenfinch. A combination of biometrics taken from live birds, faecal analysis, and behavioural observations provide an effective and efficient system for identifying the presence of salmonellosis within greenfinch.     

Phylogenetic relations among the South American thynnine tiphiid wasps (Hymenoptera)

Abstract. Phylogenetic relationships among the South American thynnine tiphiids are analysed, using previously unused characters from the female head, male and female terminalia, mouthparts and thorax. A new tribe, Scotaenini, is proposed to include the South American genera: Scotaena, Anodontyra, Pseudelaphroptera, Parelaphroptera, Glottynoides, Glottynnus, Rostrynnus and Ornepetes. One genus, Aelurus , is the only neotropical representative of the tribe Rhagigasterini. The remaining South American genera belong to the Thynnini. In addition, keys to and a synonymic checklist of the South American genera are included. One specific synonymy ( Anodontyra interrupta Duran 1941 with A.tricolor Westwood 1835), and one generic synonymy ( Pseudornepetes Duran 1941 with Pseudelaphroptera Ashmead 1903) are proposed. Telephoromyia exsecta Turner is newly transferred to Spilothynnus.     

Effect of tracheosyringeal denervation on call in greenfinch ( Carduelis sinica)

After sections of left or right tracheosyringeal nerve (NXⅡts), greenfinches may repeat everyday calls, with no effect on temporal properties. It is suggested that either side of syrinx may produce sound alone and ipsilateral innervation of NXⅡts for the syringeal muscles. After section of left NXIIts, the bird produces the vocal pattern of partial tone increase, and effects on the sound intensity and sentence length average 1.4 and 2.8 times those after section of right NXIIts, suggesting that the innervation of NXIIts has left side dominance. After bilateral section of NXIIts, the call rhythm in company with expiratory motions is 98-146 times/min,on an average, and lose all sentence types and syllable structure of normal call. But the call spectra produced by tympaniform membrane vibrations without innervation still reserve frequency components similar to the tonic frequency and harmonics of normal calls.     

Aktivit?tsuntersuchungen an Tagziehern(Carduelis carduelis)

Ohne Zusammenfassung     

Effect of tracheosyringeal denervation on call in greenfinch ( Carduelis sinica)

After sections of left or right tracheosyringeal nerve (NXⅡts), greenfinches may repeat everyday calls, with no effect on temporal properties. It is suggested that either side of syrinx may produce sound alone and ipsilateral innervation of NXⅡts for the syringeal muscles. After section of left NXIIts, the bird produces the vocal pattern of partial tone increase, and effects on the sound intensity and sentence length average 1.4 and 2.8 times those after section of right NXIIts, suggesting that the innervation of NXIIts has left side dominance. After bilateral section of NXIIts, the call rhythm in company with expiratory motions is 98-146 times/min,on an average, and lose all sentence types and syllable structure of normal call. But the call spectra produced by tympaniform membrane vibrations without innervation still reserve frequency components similar to the tonic frequency and harmonics of normal calls.     

Effect of tracheosyringeal denervation on call in greenfinch (Carduelis sinica)

After sections of left or right tracheosyringeal nerve (NXIIts), greenfinches may repeat everyday calls, with no effect on temporal properties. It is suggested that either side of syrinx may produce sound alone and ipsilateral innerration of NXIIts for the syringeal muscles. After section of left NXIIts, the bird produces the vocal pattern of partial tone increase, and effects on the sound intensity and sentence length average 1.4 and 2.8 times those after section of right NXIIts, suggesting that the innervation of NXIIts has left side dominance. After bilateral section of NXIIts, the call rhythm in company with expiratory motions is 98–146 times/min, on an average, and lose all sentence types and syllable structure of normal call. But the call spectra produced by tympaniform membrane vibrations without innervation still reserve frequency components similar to the tonic frequency and harmonics of normal calls.     

Differential selection of North American and Scandinavian conifer browse by northwestern moose (Alces alces andersoni) in winter

Scandinavian moose (Alces alces) eat Scots pine (Pinus sylvestris) in winter. Although North American moose are known to eat conifers such as true firs (Abies spp.) in winter, substantial consumption of pine by moose in North America has not been documented. Here, we document short-term winter preferences of human-habituated northwestern moose (Alces alces andersoni) for branches of mature North American and European conifer species as determined by a cafeteria-style feeding trial. Moose selected for species such as Douglas fir (Pseudotsuga menziesii; from which they took the smallest bite diameters) while avoiding species such as lodgepole pine (Pinus contorta; from which they took the largest bites) and hybrid white spruce (Picea glauca × engelmanii). The amount of species-specific biomass consumed by moose was negatively correlated with bite diameters taken from branches of those species and did not appear to be significantly influenced by differences in twig morphology between species. Our trial suggests that northwestern moose readily consume conifers in winter and, from the species we tested, prefer Douglas fir. While no clear preference existed between Scots pine and lodgepole pine, moose avoided lodgepole pine, but not Scots pine, relative to Douglas fir. Our trial suggests that northwestern moose are more likely to feed on the branches of Douglas fir than pine, which may be of interest to foresters managing conifers within the North American range of moose, particularly where Scots pine are being considered for planting.     

冬枣对不同形态氮素的吸收与利用

以2年生盆栽鲁北冬枣为试材,研究了其对尿素、甘氨酸（Gly）和谷氨酸（Glu）的吸收利用与响应特性．结果表明：3种形态氮均可被冬枣吸收利用,与尿素相比,氨基酸态氮吸收的量较少．若尿素的吸收量以100％计,则叶片对Gly和Glu的相对吸收量分别为28．88％和11．73％,吸收到的氮素主要分配到叶片和枣头枝中;而根对Gly和Glu的相对吸收量则分别为50．48％和42．72％．冬枣吸收尿素、Gly和Glu后,叶片中的谷草转氨酶（GOT）和谷丙转氨酶（GPT）活性提高,可溶性蛋白质含量增加;但不同形态氮素处理对硝酸还原酶（NR）活性的影响存在差异,尿素可显著提高NR活性,Glu对NR活性影响不大,Gly降低了NR活性．与尿素相比,氨基酸态氮能明显提高冬枣果实的着色个数、着色面积以及果实中可溶性固形物含量．     

Dormancy-inducing factors of rubber litter beetle, Luprops tristis (Coleoptera: Tenebrionidae)

Abstract  The effect of photoperiod, temperature, humidity, rainfall and moisture were examined on the annual migration of Luprops tristis (Fabricius, 1801) (Coleoptera: Tenebrionidae) from rubber plantations to shelters, and the induction of 9 months dormancy thereafter. Results confirm the role of rainfall-mediated wetness from summer showers as the cue that induces dormancy in Luprops tristis and provide further proof to the function and significance of moisture in diapause induction in tropical insects. Other factors did not have any significant independent effect on migration and dormancy induction. Reserve food accumulation by teneral adults well ahead of the onset of adverse conditions and the non-return of beetles to the field in short-term favorable conditions strongly indicate that Luprops tristis has evolved the ability to "predict" and avoid adverse conditions and the inheritance of dormancy-regulating factors from the parent generation.     

Review of winter trophic relations of soricine shrews

This paper attempts to review all those factors that affect the winter trophic relations of soricines in northern, Holarctic areas, from physiological and ecological aspects to prey and predators. Winter is generally a time of food scarcity and low temperatures, often accompanied by snow cover. Winter shrews are characterized by decreased metabolic rates, longer periods in the nest, short foraging periods and the subsequent decreased need to forage. In smaller species the diet generally consists of epigean fauna, while in larger species hypogean fauna is also included, the proportions of which vary seasonally. In areas of snow cover their diets are derived from the subnivean fauna, i.e. soil and litter fauna, overwintering on the soil surface, and consist of many insects, especially beetles, arachnids, small vertebrates and carrion. Their predators include owls and, to a lesser extent, weasels and foxes.     

The effect of mobbing vocalizations on risk perception in common mynas (Acridotheres tristis)

Journal of Ethology - Animals emit predator-elicited calls in response to potential predation threats. These vocalizations induce a variety of anti-predator behaviors in conspecific receivers...