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1.
Mare Haider Silvia Dorn Claudio Sedivy Andreas Müller 《Biological journal of the Linnean Society. Linnean Society of London》2014,111(1):78-91
Within the genus Osmia, the three subgenera Osmia, Monosmia, and Orientosmia form a closely‐related group of predominantly pollen generalist (‘polylectic’) mason bees. Despite the great scientific and economic interest in several species of this clade, which are promoted commercially for orchard pollination, their phylogenetic relationships remain poorly understood. We inferred the phylogeny of 21 Osmia species belonging to this clade by applying Bayesian and maximum likelihood methods based on five genes and morphology. Because our results revealed paraphyly of the largest subgenus (Osmia s.s.), we synonymized Monosmia and Orientosmia under Osmia s.s. Microscopical analysis of female pollen loads revealed that five species are specialized (‘oligolectic’) on Fabaceae or Boraginaceae, whereas the remaining species are polylectic, harvesting pollen from up to 19 plant families. Polylecty appears to be the ancestral state, with oligolectic lineages having evolved twice independently. Among the polylectic species, several intriguing patterns of host plant use were found, suggesting that host plant choice of these bees is constrained to different degrees and governed by flower morphology, pollen chemistry or nectar availability, thus supporting previous findings on predominantly oligolectic clades of bees. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 78–91. 相似文献
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Oskar Wasielewski Tatiana Wojciechowicz Karol Giejdasz Natraj Krishnan 《Insect Science》2015,22(4):512-520
The effects of enhanced UV‐B radiation on the oogenesis and morpho‐anatomical characteristics of the European solitary red mason bee Osmia bicornis L. (Hymenoptera: Megachilidae) were tested under laboratory conditions. Cocooned females in the pupal stage were exposed directly to different doses (0, 9.24, 12.32, and 24.64 kJ/m2/d) of artificial UV‐B. Our experiments revealed that enhanced UV‐B radiation can reduce body mass and fat body content, cause deformities and increase mortality. Following UV exposure at all 3 different doses, the body mass of bees was all significantly reduced compared to the control, with the highest UV dose causing the largest reduction. Similarly, following UV‐B radiation, in treated groups the fat body index decreased and the fat body index was the lowest in the group receiving the highest dose of UV radiation. Mortality and morphological deformities, between untreated and exposed females varied considerably and increased with the dose of UV‐B radiation. Morphological deformities were mainly manifested in the wings and mouthparts, and occurred more frequently with an increased dose of UV. Cell death was quantified by the Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay (DNA fragmentation) during early stages of oogenesis of O. bicornis females. The bees, after UV‐B exposure exhibited more germarium cells with fragmented DNA. The TUNEL test indicated that in germarium, low doses of UV‐B poorly induced the cell death during early development. However, exposure to moderate UV‐B dose increased programmed cell death. In females treated with the highest dose of UV‐B the vast majority of germarium cells were TUNEL‐positive. 相似文献
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The foraging and nesting performance of bees can provide important information on bee health and is of interest for risk and impact assessment of environmental stressors. While radiofrequency identification (RFID) technology is an efficient tool increasingly used for the collection of behavioral data in social bee species such as honeybees, behavioral studies on solitary bees still largely depend on direct observations, which is very time‐consuming. Here, we present a novel automated methodological approach of individually and simultaneously tracking and analyzing foraging and nesting behavior of numerous cavity‐nesting solitary bees. The approach consists of monitoring nesting units by video recording and automated analysis of videos by machine learning‐based software. This Bee Tracker software consists of four trained deep learning networks to detect bees that enter or leave their nest and to recognize individual IDs on the bees’ thorax and the IDs of their nests according to their positions in the nesting unit. The software is able to identify each nest of each individual nesting bee, which permits to measure individual‐based measures of reproductive success. Moreover, the software quantifies the number of cavities a female enters until it finds its nest as a proxy of nest recognition, and it provides information on the number and duration of foraging trips. By training the software on 8 videos recording 24 nesting females per video, the software achieved a precision of 96% correct measurements of these parameters. The software could be adapted to various experimental setups by training it according to a set of videos. The presented method allows to efficiently collect large amounts of data on cavity‐nesting solitary bee species and represents a promising new tool for the monitoring and assessment of behavior and reproductive success under laboratory, semi‐field, and field conditions. 相似文献
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- Wild bees are important pollinators for agricultural crops and solitary species such as Osmia bicornis are particularly suitable for pollination management. Wild bees share floral resources with managed honey bees and may be exposed to emerging infectious diseases. Although studies have explored the prevalence of pathogens in solitary wild bee species, data regarding the impact of pathogens on solitary bee health are lacking.
- We carried out experiments examining whether the solitary bee species O. bicornis is susceptible to infection with the emerging pathogen Nosema ceranae and recorded the impact of exposure on survival.
- The results obtained indicate that N. ceranae may be able to infect O. bicornis but its impact on host fitness is negligible: survival rates did not differ between control and inoculated bees, although male survival was marginally lower after infection. To explore the possible field‐relevance of our findings, we collected wild bees near an infected and a non‐infected hive and showed that N. ceranae was shared between managed and wild bees, although only the in presence of infected honey bees.
- The findings of the present study show that O. bicornis is susceptible to pathogen spillover and could act as a potential reservoir host for N. ceranae in pollinator networks. Additional studies on this species incorporating sublethal effects, multiple infections and other interacting stressors are warranted.
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The free-swimming early larval stages of Argulus foliaceus (Linneaus) (Branchiura) are studied using digital video, light microscopy, and SEM. We analyze and document the mode of swimming in the hatching stage of A. foliaceus and the subsequent juvenile stages with fully developed thoracopods. We present new observations and an analysis of the functional morphology of a cleaning behavior in the first stage. This stage swims very efficiently using the large exopods of the second antennae in concert with the mandibular palp (naupliar limbs), while the subsequent stages use the now developed thoracopods for propulsion. This posterior shift in propulsion is similar to--but independent from--what is seen in other crustaceans. The hatching stage has previously been referred as a \"metanauplius\" but as the first and second maxillae are developed and active, and buds of all four thoracopods are present, it is too advanced to be included in the naupliar phase. The hooks of the first antennae and the distal hooks of the maxillae are demonstrated to function not only as attachment organs (to the host), but also to play a significant role in the cleaning of the naupliar swimming appendages. A digital video-based analysis of the swimming mode is provided. The larval swimming pattern is generally similar to that of other crustaceans such as Branchiopoda and Cirripedia, but autapomorphies of the Branchiura include the following: 1) While actively swimming, the naupliar appendages are almost straight during the recovery stroke and 2) they have a relatively small deflection during movement ( approximately 25 degrees or approximately 35 degrees for mandible and second antenna respectively), 3) the larval mandible has a uniramous palp which is the retained exopod. The morphological implications of the transition from the possibly nonfeeding pelagic, or free-swimming, first larval stage to the feeding, parasitic second stage are discussed and compared with other crustaceans. 相似文献
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Yuichi Mochizuki 《Invertebrate reproduction & development.》2017,61(3):189-199
Postembryonic developmental stages of an endoparasitic pycnogonid, Ammothella biunguiculata in Izu Peninsula, Japan are described. Eleven stages were identified beginning with a protonymphon larva attached to the male oviger. We found endoparasitic individuals in the host actinian from the second to tenth instar, and forms in the ninth stage to adult were found free-living. This indicates a transition from being endoparasitic to free-living during the ninth to tenth instar stages. The first instar protonymphon attached to the adult male oviger has a gland duct on the anterior margin of each chelifore scape which completely disappears with the second instar. The disappearance of the chelifore gland duct coincides with the beginning of an endoparasitic stage in the development of this species. Although the larval morphology and the postembryonic development of pycnogonids have been summarized by several authors, the present study concludes that much remains to be learnt. 相似文献
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G. Guerao R. Simoni S. Cannicci K. Anger 《Invertebrate reproduction & development.》2013,57(2):100-109
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Sixteen tests were conducted with four antimicrobial agents that are routinely incorporated into lepidopterous larval diets for bacterial and fungal inhibition. The agents tested in all possible combinations were benomyl, chlortetracycline, sorbic acid, and methyl P-hydroxybenzoate. Those combinations that contained benomyl and sorbic acid in the formula were effective in complete microbial suppression during the larval portion of the 35-day testing period. Insect development in plastic cups of test diets with benomyl and sorbic acid averaged 97 and 93% pupation and adult emergence, respectively. The 12 tests that did not contain benomyl and sorbic acid were contaminated with some of the following fungi: Aspergillus niger, A. flavus, Rhizopus nigricans, Cladosporium, Fusarium, yeasts, or the bacterium, Bacillus subtilis. Microorganisms in Heliothis spp. larvae from mass-rearing diets were tested, examined, and identified. Bacteria recovered from laboratory-reared Heliothis larvae included Pseudomonas aeruginosa, P. maltophilia, Micrococcus luteus, α-hemolytic Streptococcus, Serratia marcescens, and S. rubidaea. Tests were conducted with sensi-discs for the selection of antimicrobials to arrest contamination in the larval digestive systems. 相似文献
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Tommaso Russo Domitilla Pulcini Emiliano Bruner Stefano Cataudella 《Journal of morphology》2009,270(1):83-96
Demersal fishes have complex life cycles that involve an ontogenetic change in morphology, physiology, and behavior, as their pelagic larval stages colonize benthic habitats. The developmental transition between larvae and juveniles leads to very complex processes of morphogenesis and differentiation. These processes primarily determine changes in external morphology, which is shaped by selective pressures to optimize performance for basic activities such as swimming, escape from predators, and feeding. Fishes have provided fertile grounds for ecomorphological investigations throughout ontogeny, as the role of changing morphology in inducing ontogenetic niche shifts is not always clear. In this framework, some studies have demonstrated that certain species undergo gradual changes, whereas other species experience threshold effects in their ecomorphological relationships during ontogeny. In this study, the intraspecific allometry of the dusky grouper was examined. Geometric morphometric tools were used to quantify shape changes through the development, and a modular approach was also applied to analyze the pattern of covariation between three distinct blocks (head, trunk, and tail). For this purpose, a two‐block Partial Least Square was computed. This method reveals that the pattern of changes in the overall body shape is the result of the modularized changes of these blocks. J. Morphol., 2009. © 2008 Wiley‐Liss, Inc. 相似文献
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R. M. Koedijk A. Folkvord A. Foss K. Pittman S. O. Stefansson S. Handeland A. K. Imsland 《Journal of fish biology》2010,76(1):1-6
Atlantic cod Gadus morhua larvae reached four‐fold (at low larval density) to 11 fold higher body mass (high larval density) at 50 days post hatch (dph) when fed zooplankton rather than enriched rotifers. A short period (22–36 dph) of dietary change affected larval growth positively if changed from enriched rotifers to natural zooplankton and negatively if prey type changed vice versa. Overall survival did not differ between the two larval groups at low larval density, but at high density the rotifer group had a higher overall survival (10·8% v. 8·9%). Long‐term growth was affected significantly by larval diet in favour of the zooplankton diet; juveniles reached a 23% higher mass in a 12 week growth period. No difference in growth performance was found between juveniles fed natural zooplankton during the larval period for 36, 22 or 14 days, but all these juveniles performed significantly better compared with the rotifer‐fed group. These findings suggest that optimal diet during a short period in the larval period can result in improved growth in both the larval and juvenile period. Improved rotifer quality may, therefore, hold a large potential for growth improvement in this species. 相似文献
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Black rhinoceros diet and browse availability was investigated in Augrabies Falls (AFNP), Karoo (KRNP) and Vaalbos National Parks (VNP) in South Africa. Rhino tracks were followed and 18,804 standard bite volumes recorded. Browse availability of each plant species was recorded by measuring 14,800 plants and calculating reachable browse volume. The diet comprised 51, 53 and 41 plant species in AFNP, KRNP and VNP, respectively, but three species accounted for more than 65% of the diet in each park, making diet less diverse than available browse in AFNP and KRNP. Browse availability explained 14%, 15% and 52% of diet selection in AFNP, KRNP and VNP, with consumption of most plant species significantly different from availability. A few plant species were so highly preferred that browsing intensities were unsustainable, while some common species were totally rejected. Pressure on the eaten browse averaged 4.4%, 14.5% and 1.3% annually of the volume in AFNP, KRNP and VNP. In the dry season, there was a two to sevenfold increase in browsing pressure on species with actively photosynthesizing tissues. A few key species, including Monechma and Zygophyllum species, were identified as potential early warning indicators of black rhino browsing impact. 相似文献
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Sander lucioperca is an organism of growing importance for the aquaculture industry. Nonetheless, the rearing of S. lucioperca larvae is proving to be a difficult task as it is facing a high mortality rate during hatching and the change to exogenous feeding. To gain insight into growth patterns during this period, the authors analysed pikeperch embryos and larvae from 9 days before hatching to 17 days after hatch. Hereby they were able to describe a natural development by using close to natural conditions based on using a direct flow-through supply of lake fresh water on specimens from a local wild population. The results show that between the early embryonic stages a steady growth was visible. Nonetheless, in between hatching and the start of exogenous feeding, a phase of growth stagnation took place. In the following larval stages, an increased growth with large size variations between individual specimens appeared. Both factors are conspicuous as they can indicate a starting point for cannibalism. With this analysis, the authors can provide a fundament to support the upcoming research on S. lucioperca and aid to optimize size-sorting procedures for a higher survival of pikeperch stock in aquaculture. 相似文献
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Nafiseh Sanjarani Vahed Hamid Reza Esmaeili Mojtaba Masoudi Mehregan Ebrahimi 《Journal of morphology》2018,279(6):747-756
The embryonic and early larval development of laboratory reared Zagros tooth‐carp, Aphanius vladykovi Coad, 1988, are described and illustrated. Development and embryogenesis start with the external fertilization of sticky, transparent and spherical telolecithal/macrolecithal eggs with a mean diameter of 1.61± 0.12 mm and it continues with meroblastic/radial cleavage, blastulation/blastula formation, epibolic cell migration during gastrulation and organogenesis resulting in a newly hatched larvae of 5.23 ± 0.09 mm in length with attached yolk sac at about 164 hr (at 24 ± 1°C) after fertilization. 相似文献
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应用二次正交旋转回归组合设计方法,筛选小菜蛾半合成人工饲料配方,以化蛹率为目标函数建立了二次回归模型,通过统计寻优获得的优化配方为:每100g人工饲料中,麦芽5g、蔗糖3.5g、菜叶粉5g、干酪素3g、螺旋藻0.75g。在温度24～26℃,相对湿度60%～70%,光照周期为13L∶11D的条件下,用该优化配方饲养小菜蛾,幼虫期8.45d,蛹期4.5d,初孵幼虫至成虫羽化的历期平均12.95d,化蛹率74.7%,羽化率94.9%,蛹重5.14mg/头,雌虫平均寿命9.5d,雄虫寿命13.5d,每雌产卵量135.67粒。与发芽菜苗饲养相比,存活率和发育速度无显著差异,蛹重和产卵量显著增加。该饲料价格低廉,配制和应用管理方便,饲养过程中不必更换饲料。 相似文献
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ANTHONY HERREL REBECCA JOACHIM BIEKE VANHOOYDONCK DUNCAN J. IRSCHICK 《Biological journal of the Linnean Society. Linnean Society of London》2006,89(3):443-454
It has been documented extensively that body size affects the physiology and musculoskeletal function of organisms. However, less well understood is how body size affects the ecology of organisms through its effects on physiology and performance. We explored the effects of body size on morphology and performance in different ontogenetic classes and sexes of a common Anolis lizard ( A. lineatopus ). Next, we tested whether these morphological and performance differences may affect functional aspects of the diet such as prey size and prey hardness. Our data showed that males, females and juveniles differ significantly in head size, head shape and bite force. Multiple regression models indicated that head shape and bite force are significantly correlated to prey size and hardness. Yet juveniles had relatively large heads and bit disproportionately hard for their size, allowing them to eat prey as large as those of females. However, for a given prey size, males and females ate more robust prey than did juveniles. Additionally, males ate relatively harder prey than did juveniles. These data suggest that: (1) body size affects the dietary ecology of animals through its effect on head size and bite force; (2) changes in head morphology independent of changes in overall size also have important effects on performance and diet. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 443–454. 相似文献
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Liam J. Zarri Sarah B. Mehl Eric P. Palkovacs Nann A. Fangue 《Journal of fish biology》2019,94(5):815-819
We reared white sturgeon Acipenser transmontanus under laboratory conditions and found that a random-forest model containing scute counts and total length predicted age significantly better than total length alone. Scute counts are rapid, inexpensive and non-lethal meristics to gather in the field. This technique could improve age estimates of imperilled sturgeon populations. 相似文献