Examining costs of induced and constitutive immune investment in Tenebrio molitor

Central to the conceptual basis of ecological immunity is the notion that immune effector systems are costly to produce, run, and/or maintain. Using the mealworm beetle, Tenebrio molitor, as a model we investigated two aspects of the costs of innate immunity. We conducted an experiment designed to identify the cost of an induced immune response, and the cost of constitutive investment in immunity, as well as potential interactions. The immune traits under consideration were the encapsulation response and prophylactic cuticular melanization, which are mechanistically linked by the melanin-producing phenoloxidase cascade. If immunity is costly, we predicted reduced longevity and/or fecundity as a consequence of investment in either immune trait. We found a measurable longevity cost associated with producing an inducible immune response (encapsulation). In contrast to other studies, this cost was expressed under ad libitum feeding conditions. We found no measurable costs for constitutive investment in immunity (prophylactic investment in cuticular colour).     

Cuticular melanisation and immune response in a butterfly: local adaptation and lack of correlation

1. Despite growing knowledge on the relationship between ecological variables and individual immune function, data on the spatial variability of immune defence in invertebrate natural populations are scarce. 2. Here, we use replicated populations of the butterfly Lycaena tityrus from different altitudes to investigate genetic variation in the melanin‐based encapsulation response. As high‐ and low‐altitude populations differ in cuticular pupal melanisation, we further tested for any associations between pupal melanisation and parasite resistance. 3. Although pupal melanisation was higher at higher compared with lower altitudes (and at a higher compared with a lower rearing temperature), any obvious relations to the encapsulation response were absent. Further phenotypic correlations within groups were significant in one out of four cases only, suggesting that in L. tityrus encapsulation operates largely independent of cuticular melanisation. 4. A significant interaction between altitude and temperature indicated that high‐altitude animals show a stronger melanisation response than low‐altitude ones at the lower temperature and vice versa, indicating local adaptation to different climates.     

Invertebrate communities delineate hydro-ecoregions and respond to anthropogenic disturbance in East-Amazonian streams

Many tropical regions lack models predicting the biological and environmental conditions expected in any given area, thus precluding the implementation of reference condition-based water policies. We focused on streams of French Guiana, and tested two predictions: geomorphology determines ecological sub-regions that have typical invertebrate communities, and diversity declines as anthropogenic pressure increases. Sixty-five stream sites were sampled for benthic invertebrates and physical–chemical variables across various watersheds. We used the Self-Organizing Map algorithm (neural network) to model relationships between invertebrate communities and environmental variables. Sites characterized by invertebrate communities clustered into two major subsets matching French Guiana’s hydro-ecoregions: the coastal alluvial plain characterized by recent sediment and low elevations, and the Guiana Shield characterized by an eroded rocky substrate and dense rainforests. Changes in community composition, and to a lesser extent taxonomic richness within each sub-region revealed ecological impacts of gold mining and logging, further clustering hydro-ecoregions into subsets of reference and impaired sites. Further analyses would, however, be needed to identify tipping points between natural and disturbed states, especially in remote headwater streams where gold mining had the harsher impact upon freshwater diversity, making upstream communities resembling the most downstream impacted ones.     

Impacts of introduced common wasps (Vespula vulgaris) on experimentally placed mealworms in a New Zealand beech forest

An introduced social wasp Vespula vulgaris may compete with native birds for honeydew and invertebrates in New Zealand forests. Experimentally hidden mealworms (Tenebrio molitor) persisted longer at two sites following wasp poisoning that at two sites where wasps were not poisoned. Mealworms persisted longer in the morning than in the afternoon within all study sites. An unusually low mealworm removal rate during a morning trial before wasp poisoning heavily influences the results of this experiment but we have no ecological reason to ignore it. Wasps may therefore be having a heavy impact on invertebrate abundance on very short time scales (within a day following dawn emergence). They may also remove cached food items that would otherwise be retrieved by the South Island robin (Petroica australis australis) during cold or dark feeding conditions.     

Digital imaging approaches for phenotyping whole plant nitrogen and phosphorus response in Bracbypodium distacbyon

This work evaluates the phenotypic response of the model grass （Brachypodium distacbyon （L.） P. Beauv.） to nitrogen and phosphorus nutrition using a combination of imaging techniques and destructive harvest of shoots and roots. Reference line Bd21-3 was grown in pots using 11 phosphorus and 11 nitrogen concentrations to establish a dose-response curve. Shoot biovolume and biomass, root length and biomass, and tissue phosphorus and nitrogen concentrations increased with nutrient concentration. Shoot biovolume, estimated by imaging, was highly correlated with dry weight （R2 〉 0.92） and both biovolume and growth rate responded strongly to nutrient availability. Higher nutrient supply increased nodal root length more than other root types. Photochemical efficiency was strongly reduced by low phosphorus concentrations as early as 1 week after germination, suggesting that this measurement may be suitable for high throughput screening of phosphorus response. In contrast, nitrogen concentration had little effect on photochemical efficiency. Changes in biovolume over time were used to compare growth rates of four accessions in response tonitrogen and phosphorus supply. We demonstrate that a time series image-based approach coupled with mathematical modeling provides higher resolution of genotypic response to nutrient supply than traditional destructive techniques and shows promise for high throughput screening and determina- tion of genomic regions associated with superior nutrient use efficiency.     

Genealogy and phylogeography of Cyprinid fish Labeo rohita （Hamilton, 1822） inferred from ATPase 6 and 8 mitochondrial DNA gene analysis

ATPase 6/8 gene （842 bp） of mitochondrial DNA was sequenced in Labeo rohita samples （n = 253） collected from nine rivers belonging to four river basins; Indus, Ganges, Brahmaputra and Mahanadi. Analysis revealed 44 haplotypes with high haplotype diversity （Hd） 0.694 and low nucleotide diversity （π） 0.001. The within population variation was larger （83.44%） than among population differences （16.56%）. The mean Fsv value （0.166; P 〈 0.05） for overall populations revealed moderate level of genetic structuring in the wild L. rohita populations. The haplotype network presented a single clade for wild L. rohita population, from different rivers. Negative values for Fu＇s index （Fs）, mismatch distribution analysis indicated period of expansion in L. rohita population. The time after recent expansion was estimated for each population, between 0.042 to 0.167 mya. The pattern of Isolation by Distance （IBD） was not significant （r = -0.113, P 〈 0.287）, when all the sampling locations were compared （Mantel test）, however, when an outlier （Indus, Brahmaputra and Mahanadi） was removed from the whole population set, a clear positive correlation between pairwise Fsv and geographic distance （Km） was seen. The analysis of data demonstrated that ATPase6/8 gene polymorphism is a potential marker to understand genetic population structure of wild L. rohita existing in different rivers. The study identified population substructure in wild L. rohita with common ancestral origin [Current Zoology 60 （4）： 460--471, 2014].     

Male size does not correlate with fertilization success in two bufonid toads that show size-assortative mating

We examined sexual size dimorphism （SSD）, mating pattem, fertilization efficiency and female reproductive traits in two bufonid toads （Bufo gargarizans and Duttaphrynus melanostictus） to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gar- garizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficieneies on average were higher in B. gargarizans （95%） than in D. melanostictus （91%）. Though differing in the degree of SSD, body size, breeding season, clutch size, egg size and fertilization efficiency, the two toads were similar in four aspects： （1） both showed size-assortative mating; （2） females did not tradeoff egg size against egg number; （3） male size, clutch size and clutch dry mass were greater in male-larger than in female-larger pairs after accounting for female snout-vent length （SVL）; and （4） the ratio of male to female SVL did not affect fertilization efficiency. Our data show that： （1） a female preference for large males is likely not important in terms of egg fertilization success; （2） a male preference for large females is likely important because larger females are more fecund; and （3） size-assortative mating arises from a male preference for large females. Our study demonstrates that male size is not always important for egg fertilization success in anurans that show size-assortative mating.     

Antipredator deception in terrestrial vertebrates

Abstract Deceptive antipredator defense mechanisms fall into three categories： depriving predators of knowledge of prey＇s presence, providing cues that deceive predators about prey handling, and dishonest signaling. Deceptive defenses in terrestrial vertebrates include aspects of crypsis such as background matching and countershading, visual and acoustic Batesian mimicry, active defenses that make animals seem more difficult to handle such as increase in apparent size and threats, feigning injury and death, distractive behaviours, and aspects of flight. After reviewing these defenses, I attempt a preliminary evaluation of which aspects of antipredator deception are most widespread in amphibians, reptiles, mammals and birds     

Molecular mechanisms of insect adaptation to plant defense： Lessons learned from a Bruchid beetle

Plants can accumulate, constitutively and/or after induction, a wide variety of defense compounds in their tissues that confer resistance to herbivorous insects. The naturally occurring plant resistance gene pool can serve as an arsenal in pest management via transgenic approaches. As insect-plant interaction research rapidly advances, it has gradually become clear that the effects of plant defense compounds are determined not only by their toxicity toward target sites, but also by how insects respond to the challenge. Insect digestive tracts are not passive targets of plant defense, but often can adapt to dietary challenge and successfully deal with various plant toxins and anti-metabolites. This adaptive response has posed an obstacle to biotechnology-based pest control approaches, which underscores the importance of understanding insect adaptive mechanisms. Molecular studies on the impact of protease inhibitors on insect digestion have contributed significantly to our understanding of insect adaptation to plant defense. This review will focus on exposing how the insect responds to protease inhibitors by both qualitative and quantitative remodeling of their digestive proteases using the cowpea bruchid-soybean cysteine protease inhibitor N system.     

Identification and characterization of genes involved in the jasmonate biosynthetic and signaling pathways in mulberry （Morus notabilis）

Jasmonate （JA） is an important phytohormone regulating growth, development, and environmental response in plants, particularly defense response against herbivorous insects. Recently, completion of the draft genome of the mulberry （Morus notabilis） in conjunction with genome sequencing of silkworm （Bombyx mori） provides an opportuni-ty to study this unique plant-herbivore interaction. Here, we identified genes involved in JA biosynthetic and signaling pathways in the genome of mulberry for the first time, with the majority of samples showing a tissue-biased expression pattern. The analysis of the representative genes 12-oxophy-todienoic acid reductase （OPRs） and jasmonate ZIM-domain （JAZs） was performed and the results indicated that the mulberry genome contains a relatively smal number of JA biosynthetic and signaling pathway genes. A gene encoding an＆amp;nbsp;important repressor, MnNINJA, was identified as an alternative splicing variant lacking an ethylene-responsive element binding factor-associated amphiphilic repression motif. Having this fundamental information wil facilitate future functional study of JA-related genes pertaining to mulberry-silkworm interactions.     

Evolution of deceit by worthless donations in a nuptial gift-giving spider

Males of the nursery web spider Pisaura mirabil usually offer an insect prey wrapped in white silk as a nuptial gift to facilitate copulation. Males exploit female foraging preferences in a sexual context as females feed on the gift during copula- tion. It is possible for males to copulate without a gift, however strong female preference for the gift leads to dramatically higher mating success for gift-giving males. Females are polyandrous, and gift-giving males achieve higher mating success, longer copulations, and increased sperm transfer that confer advantages in sperm competition. Intriguingly, field studies show that ap- proximately one third of males carry a worthless gift consisting of dry and empty insect exoskeletons or plant fragments wrapped in white silk. Silk wrapping disguises gift content and females are able to disclose gift content only after accepting and feeding on the gift, meanwhile males succeed in transferring sperm. The evolution of deceit by worthless gift donation may be favoured by strong intra-sexual competition and costs of gift-construction including prey capture, lost foraging opportunities and investment in silk wrapping. Females that receive empty worthless gifts terminate copulation sooner, which reduces sperm transfer and likely disadvantages males in sperm competition. The gift-giving trait may thus become a target of sexually antagonistic co-evolution, where deceit by worthless gifts leads to female resistance to the trait. We discuss factors such as female mating rate and intensity of sperm competition that may shape the evolution of male deception, and how ecological factors may influence the evolution and maintenance of worthless gifts as an evolutionarily stable alternative mating strategy by frequency dependent selection     

Uropygial gland volatiles may code for olfactory information about sex,individual, and species in Bengalese finches Lonchura striata

Over-shadowed by eye-catching vocal and visual signals, chemical communication has long been overlooked in birds. This study aimed at exploring whether volatile composition of the uropygial gland secretion （UGS） of birds was associated with the information about sex, individual and species. By using dichloromethane extraction and gas chromatography-mass spectrometry （GC-MS）, we analyzed the UGS volatiles of domesticated Bengalese finches （ Lonchura striata, Estrildiea） which is also known as white-rumped munias. We characterized 16 volatile molecules from the UGS, including eight n-alkanols, five diesters, an ester, an aldehyde and a fatty acid, and quantified them in terms of GC peak area percentages （relative abundances） . Among these compounds, hexadecanol and octadecanol were major components in both sexes. The former was richer in males than in females and the latter richer in females than in males, suggesting that they might be male and female pheromone candidates, respectively. The high inter-individual variations, in relative abundance, of the UGS volatiles implied that these compounds might carry information about individuality. The similarity between GC profiles of the UGS and wing feather from same individuals indicates that the birds might preen the secretion to their feathers to transmit chemical cues. Additionally, by comparing with three sympatric passerine species, i. e., zebra finches Taeniopygia guttata, yellow-bowed buntings Emberiza chrysophrys and rooks Corvus frugilegus, we found that the composition of C13 - C18 alkanols in the UGS might code for information about species. Our study also showed that quantitative differences （degree） of same UGS volatiles might be the key for the Bengalese finch to code for information about sex and individuality whereas both the kind and degree of UGS constituents could be utilized to code for information about species [ Current Zoology 55 （5）： 357-365, 2009].     

New Replacement Name for Rana paradoxa Mocquard, 1890 with Designations of Lectotypes for Rana paradoxa and Rana conspicil- lata Giinther, 1872： Both Synonymized with Limnonectes kuhlii （Tschudi, 1838） （Dicroglossidae： Dicroglossinae）

Fanged frogs, now called Limnonectes kuhlii, from Borneo are remotely related to true Javanese L. kuhliL For future taxonomy of Bornean fanged frogs, we fix the nomenclatural status of two existing names, Rana conspicillata Giunther, 1872 and Rana paradoxa Mocquard, 1890. Morphological comparison of the type-series revealed heterospecific relationships of the two species. For R. conspicillata, we designate BMNH 1947.2.29.20 as the lectotype, and for R. para doxa, we also designate MNHN 1889.222 as the lectotype and propose a replacement name Limnonectes mocquardi, in order to stabilize their nomenclature.     

Mitochondrial pyruvate dehydrogenase E1 of Nosema bombycis： A marker in Microsporidian evolution

Microsporidia are a group of intracelluar eukaryotic parasites, which can infected almost all animals, including human beings. Till now, no mitochodria but mitosome, a remnant of mitochondria was discovered in this phylum. We present here the mitochondrial pyruvate dehydrogenase El （PDH, including PDHα and PDHβ） of the microsporidian Nosema bombycis, the pathogen of silkworm pebrine. Compared with PDH of microsporidian Encephalitozoon cuniculi and Antonospora locustae, both subunits are eonscrced. The phylogeny indicated that both subunits are mitochondrial. The syntenic maps revealed the subunits organization of NbPDH is distributed in different scaffolds, similar to that of EcPDH but different with AIPDH, and the relationship between phylogeny tree and organization of PDH suggest that the AlPDH subunits organization is the ancestral style of microsporidia, and through the genome evolution, the reshuffling of the chromosome of microsporidia occurred, the adjacent style of ALPDHE1 organization changed, and the two subunits separated and located to different chromosomes in E. cuniculi. For N. bombycis and N. ceranae, they locate to different scaffolds. In order to determine NbPDH subcellular localizations, we prepared the polyclonal antibodies against NbPDH prokaryotic fusion proteins, and adopted the colloidal gold immunological electron microscopy, the expression signals of NbPDH were observed in spores however, the subcellular localization were not definited. In general, through comparison of three mierosporidian PDH molecular phylogeny, subunits organization in chromosomes, localization indicated that PDH is an interesting marker in microsporidia evolution     

The impact of attractants on pocket gopher trapping

Pocket gophers （Geomyidae） have an extensive impact on both natural and agricultural systems. Trapping is a tech- nique often used to sample and manage these populations. The identification of an attractant that increases capture rates of pocket gophers would greatly assist researchers and pest management professionals alike. Therefore, we tested the attractiveness of four attractants （peanut butter, anise, grapefruit attractant, and carrot） plus a control （no attractant） using uncovered and covered trap sets to determine what impact they have on visitation and capture rates of pocket gophers. We also determined how the impact of cover status and attractants differ across varying weights and gender of pocket gophers. We found no direct effect of any attracrant on visitation and capture rates of pocket gophers, nor on the gender of captured individuals. However, when no attractant was used, the mtmber of pocket gophers captured per 100 trap nights was greater when trap sets were uncovered vs. when covered, and capture rates were generally high and consistent when using peanut butter as an attractant. Additionally, we noted that covered trap sets that were baited with peanut butter yielded heavier pocket gopher captures than uncovered trap sets using this same attractant. This is key, given the difficulty associated with capturing older, more experienced individuals. Combined with data from a previous investigation, this suggests that there is no advantage to using any attractant when utilizing uncovered trap sets, but there is likely some benefit to using peanut butter in covered trap sets [Current Zoology 60 （4）： 472-478, 2014].     

Brain GABA and glutamate levels in workers of two ant species （Hymenoptera： Formicidae）： Interspecific differences and effects of queen presence/absence

Presence of amino acid neurotransmitters gamma-aminobutyric acid （GABA） and glutamate （Glu） in ant brains was reported in very few studies. To learn more about factors influencing GABA and Glu levels in ant brains, we applied high-performance liquid chromatography to measure levels of these compounds in single brains of workers of 2 ant species, Myrmica ruginodis （subfamily Myrmicinae） and Formica polyctena （subfamily Formicinae） taken from queenright/queenless colony fragments and tested in dyadic aggression tests consisting of an encounter with a nestrnate, an alien conspecific or a small cricket. Brain glutamate levels were higher than those of GABA in both tested species. Brain GABA levels （in μmol/brain） and GABA ： Glu ratio were higher in M. ruginodis （a submissive species） than in E polyctena （a dominant, aggressive species） in spite of smaller brain weight of M. ruginodis. Brain glutamate levels （in μmol/brain） did not differ between the tested species, which implies that glutamate concentration （in μmol/mg of brain tissue） was higher in M. ruginodis. Queen absence was associated with increased worker brain GABA levels in E polyctena, but not in M. ruginodis. No significant effects of opponent type were discovered. As GABA agonists enhance friendly social behavior in rodents, we hypothesize that elevated brain GABA levels of orphaned workers of F.polyctena facilitate the adoption of a new queen. This is the first report providing information on GABA and glutamate levels in single ant brains and documenting the effects of queen presence/absence on brain levels of amino acid neurotransmitters in workers of social Hymenoptera.     

Variation in the timing of river entry of Atlantic salmon （Salmo salar L. ） in the Baltic

The timing of river entry in the Atlantic salmon is known to depend on genetic, demographic and environmental factors, but little is known about the relative magnitude of among population and among year variation and covariation in this respect in natural state Atlantic salmon rives. To investigate this, variability in the timing of river entry in three historical Finnish Atlantic salmon populations were analyzed using salmon trap data collected during 1870- 1902. The analyses reveled that 1 ） the timing of river entry differed substantially and consistently among the rivers, and that 2） variation among the rivers was much larger than variation among years. Annual variations were not explained by regional environmental conditions, whereas in one river the timing of the local flood peak was a significant predictor of the timing of river entry. Differences in the timing of salmon entry to geographically closely situated rivers suggests that a regionally fixed opening date for coastal fisheries might not be the best management strategy as it may lead to uneven exploitation of salmon populations from different rivers [ Current Zoology 55 （5） ： 342 - 349, 2009] .