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1.
J Anim Ecol ; 93(2): 183-195, 2024 02.
Article in English | MEDLINE | ID: mdl-38192015

ABSTRACT

Understanding how different organisms cope with changing temperatures is vital for predicting future species' distributions and highlighting those at risk from climate change. As ectotherms, butterflies are sensitive to temperature changes, but the factors affecting butterfly thermoregulation are not fully understood. We investigated which factors influence thermoregulatory ability in a subset of the Mediterranean butterfly community. We measured adult thoracic temperature and environmental temperature (787 butterflies; 23 species) and compared buffering ability (defined as the ability to maintain a consistent body temperature across a range of air temperatures) and buffering mechanisms to previously published results from Great Britain. Finally, we tested whether thermoregulatory ability could explain species' demographic trends in Catalonia. The sampled sites in each region differ climatically, with higher temperatures and solar radiation but lower wind speeds in the Catalan sites. Both butterfly communities show nonlinear responses to temperature, suggesting a change in behaviour from heat-seeking to heat avoidance at approximately 22°C. However, the communities differ in the use of buffering mechanisms, with British populations depending more on microclimates for thermoregulation compared to Catalan populations. Contrary to the results from British populations, we did not find a relationship between region-wide demographic trends and butterfly thermoregulation, which may be due to the interplay between thermoregulation and the habitat changes occurring in each region. Thus, although Catalan butterfly populations seem to be able to thermoregulate successfully at present, evidence of heat avoidance suggests this situation may change in the future.


Subject(s)
Butterflies , Animals , Butterflies/physiology , Body Temperature Regulation , Temperature , Hot Temperature , Ecosystem , Climate Change
2.
J Insect Conserv ; 25(4): 611-628, 2021.
Article in English | MEDLINE | ID: mdl-34127906

ABSTRACT

Abstract: The Duke of Burgundy butterfly (Hamearis lucina) is known to have specific habitat requirements for its larval foodplants. However, no studies have yet investigated whether these preferences vary over time or in relation to climate, and there is a paucity of data on whether management on reserves can replicate preferred conditions. Here, we build upon existing research to confirm which characteristics Duke of Burgundy prefer for their larval foodplants, whether preferences remain consistent across years, and whether conservation management on reserves can replicate these conditions. Fieldwork was carried out at Totternhoe Quarry Reserve, a chalk grassland site in Bedfordshire, UK. Confirming previous research, we found that large Primula plants in dense patches were chosen for oviposition, but that once chosen there was no preference to lay eggs on a plant's largest leaf. Chosen foodplants were also more sheltered and in closer proximity to scrub than their controls. However, at a finer scale, we found little evidence for any preference based on differences in microclimate, or vegetation height immediately surrounding the plants. This suggests features that alter microclimatic conditions at a larger scale are relatively more important for determining the suitability of oviposition sites. Nearly all preferences remained consistent over time and did not vary between years. Management of scrub on the reserve was able to reproduce some preferred habitat features (high plant density), but not others (large plant size). Implications for insect conservation: The consistency of findings across years, despite inter-annual variation in temperature, rainfall and number of adults, indicates that the Duke of Burgundy is conservative in its foodplant choice, highlighting its need for specific habitat management. Targeted management for foodplants could form part of a tractable set of tools to support Duke of Burgundy numbers on reserves, but a careful balance is needed to avoid scrub clearance leaving plants in sub-optimal conditions.

3.
J Dent Res ; 99(11): 1221-1227, 2020 10.
Article in English | MEDLINE | ID: mdl-32609569

ABSTRACT

Orofacial clefts and their management impose a substantial burden on patients, on their families, and on the health system. Under the current standard of care, affected patients are subjected to a lifelong journey of corrective surgeries and multidisciplinary management to replace bone and soft tissues, as well as restore esthetics and physiologic functions while restoring self-esteem and psychological health. Hence, a better understanding of the dynamic interplay of molecular signaling pathways at critical phases of palate development is necessary to pioneer novel prenatal interventions. Such pathways include transforming growth factor-ß (Tgfß), sonic hedgehog (Shh), wingless-integrated site (Wnt)/ß-catenin, bone morphogenetic protein (Bmp), and fibroblast growth factor (Fgf) and its associated receptors, among others. Here, we summarize commonly used surgical methods used to correct cleft defects postnatally. We also review the advances made in prenatal diagnostics of clefts through imaging and genomics and the various in utero surgical corrections that have been attempted thus far. An overview of how key mediators of signaling that drive palatogenesis are emphasized in the context of the framework and rationale for the development and testing of therapeutics in animal model systems and in humans is provided. The pros and cons of in utero therapies that can potentially restore molecular homeostasis needed for the proper growth and fusion of palatal shelves are presented. The theme advanced throughout this review is the need to develop preclinical molecular therapies that could ultimately be translated into human trials that can correct orofacial clefts at earlier stages of development.


Subject(s)
Cleft Lip , Cleft Palate , Animals , Cleft Lip/genetics , Cleft Lip/surgery , Cleft Palate/genetics , Cleft Palate/surgery , Esthetics, Dental , Female , Hedgehog Proteins , Humans , Palate , Pathology, Molecular , Pregnancy
4.
Proc Biol Sci ; 283(1843)2016 11 30.
Article in English | MEDLINE | ID: mdl-27881743

ABSTRACT

The BA allele of the Drosophila cytochrome P450 gene Cyp6g1 confers resistance to a range of insecticides. It is also subject to intralocus sexual conflict when introgressed into the Canton-S background, whose collection predates the widespread use of insecticides. In this genetic background, the allele confers a pleiotropic fitness benefit to females but a cost to males, and exhibits little sexual dimorphism in conferred insecticide resistance. It is unclear whether these sexually antagonistic effects also exist in current populations that have naturally evolved with insecticides, where genetic modifiers that offset male costs might be expected to evolve. Here, we explore these issues using Drosophila melanogaster caught recently from an Australian population in which the BA allele naturally segregates. While we find increased fecundity in insecticide-resistant BA females and no consistent evidence of fitness costs in males, experimental evolution indicates balancing selection at the locus. We suggest that this apparent discrepancy may be due to reduced investment in reproduction in resistant males. Our results at the population level are consistent with previous work, and suggest that individual-level fitness assays do not always capture sexually antagonistic fitness effects that emerge in a population context.


Subject(s)
Drosophila melanogaster/genetics , Genetic Fitness , Genetic Pleiotropy , Insecticide Resistance/genetics , Sex Characteristics , Alleles , Animals , Australia , Cytochrome P-450 Enzyme System/genetics , Drosophila Proteins/genetics , Female , Fertility , Male
5.
Geobiology ; 13(4): 316-39, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25917609

ABSTRACT

Pre-Cambrian atmospheric and oceanic redox evolutions are expressed in the inventory of redox-sensitive trace metals in marine sedimentary rocks. Most of the currently available information was derived from deep-water sedimentary rocks (black shale/banded iron formation). Many of the studied trace metals (e.g. Mo, U, Ni and Co) are sensitive to the composition of the exposed land surface and prevailing weathering style, and their oceanic inventory ultimately depends on the terrestrial flux. The validity of claims for increased/decreased terrestrial fluxes has remained untested as far as the shallow-marine environment is concerned. Here, the first systematic study of trace metal inventories of the shallow-marine environment by analysis of microbial carbonate-hosted pyrite, from ca. 2.65-0.52 Ga, is presented. A petrographic survey revealed a first-order difference in preservation of early diagenetic pyrite. Microbial carbonates formed before the 2.4 Ga great oxygenation event (GOE) are much richer in pyrite and contain pyrite grains of greater morphological variability but lesser chemical substitution than samples deposited after the GOE. This disparity in pyrite abundance and morphology is mirrored by the qualitative degree of preservation of organic matter (largely as kerogen). Thus, it seems that in microbial carbonates, pyrite formation and preservation were related to presence and preservation of organic C. Several redox-sensitive trace metals show interpretable temporal trends supporting earlier proposals derived from deep-water sedimentary rocks. Most notably, the shallow-water pyrite confirms a rise in the oceanic Mo inventory across the pre-Cambrian-Cambrian boundary, implying the establishment of efficient deep-ocean ventilation. The carbonate-hosted pyrite also confirms the Neoarchaean and early Palaeoproterozoic ocean had higher Ni concentration, which can now more firmly be attributed to a greater proportion of magnesian volcanic rock on land rather than a stronger hydrothermal flux of Ni. Additionally, systematic trends are reported for Co, As, and Zn, relating to terrestrial flux and oceanic productivity.


Subject(s)
Fossils/microbiology , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Iron/chemistry , Metals/analysis , Sulfides/chemistry , Archaea/metabolism , Bacteria/metabolism , Carbonates/metabolism , Earth, Planet , Evolution, Planetary , Seawater/chemistry
7.
Vet Rec ; 125(4): 83-6, 1989 Jul 22.
Article in English | MEDLINE | ID: mdl-2773237

ABSTRACT

A serological study of antibodies to Ehrlichia risticii was carried out on 10 species of wild and domestic mammals found on or near 21 horse farms in an area of the USA in which Potomac horse fever is endemic. No antibodies were found in 133 peridomestic rodents (Norway rats and house mice), nor in 108 wild rodents (white-footed mice and meadow voles) captured on farms. Three of the six domestic animal species examined, cats, pigs and a goat, showed serological evidence of exposure to E risticii. Seropositive animals were detected on three of the 21 premises. The eight seropositive cats (of 48 cats tested) were on two farms, and the three seropositive pigs (of 14 tested) were all on one farm which lay some 3 km from where the one seropositive goat (of three tested) was found. None of the 79 dogs, 75 cattle and seven sheep tested had antibodies to E risticii. The significance of these findings is discussed in the light of current understanding of the transmission of Potomac horse fever and of the epidemiology of other related ehrlichial diseases.


Subject(s)
Antibodies, Bacterial/analysis , Disease Reservoirs , Ehrlichia/immunology , Horse Diseases/epidemiology , Rickettsiaceae Infections/veterinary , Rickettsiaceae/immunology , Animals , Animals, Domestic/immunology , Animals, Wild/immunology , Female , Horse Diseases/transmission , Horses , Maryland , Rickettsiaceae Infections/epidemiology , Rickettsiaceae Infections/transmission
8.
Poult Sci ; 68(6): 833-5, 1989 Jun.
Article in English | MEDLINE | ID: mdl-2771850

ABSTRACT

A simple quantitative method (moving sticky tape) to monitor house fly populations in commercial caged layer houses was described and compared with a standard monitoring (spot card) method routinely used in egg houses. Numbers of flies counted by the sticky tape method were highly correlated (.78, P = .005) with those obtained with the spot card method. The moving sticky tape method is quicker and easier to use than the spot card method. The moving sticky tape method has been used satisfactorily since 1985 by the authors and cooperating service managers of commercial caged layer houses to monitor house flies in integrated pest management programs. A fixed sticky tape method was also compared with the spot card method; there was no significant correlation between the numbers of flies counted by these two methods.


Subject(s)
Chickens , Diptera , Housing, Animal , Animals , Female , Insect Control/methods
9.
J Am Mosq Control Assoc ; 4(4): 431-5, 1988 Dec.
Article in English | MEDLINE | ID: mdl-2906356

ABSTRACT

A horse-baited trap and a mobile insect sorting table were used to conduct an arthropod survey for potential vectors of Potomac Horse Fever in southern Maryland and northern Virginia. The trap and table worked effectively for the live collection and sorting of haemophagous Diptera such as: Simulium spp., Stomoxys calcitrans, Musca autumnalis, Tabanus spp. and Chrysops spp. during the diurnal collections periods, and Culicoides spp. during the crepuscular periods. The trap was not as convenient for live collection of mosquito species during the nocturnal period. Modifications to the trap design was suggested for mosquito live trapping.


Subject(s)
Diptera/classification , Horses/parasitology , Insect Control/instrumentation , Insect Vectors/classification , Animals , Culicidae/classification , Ehrlichia , Equipment Design , Horse Diseases/transmission , Population Surveillance , Rickettsiaceae Infections/transmission , Rickettsiaceae Infections/veterinary
13.
Prog Clin Biol Res ; 178: 213-9, 1985.
Article in English | MEDLINE | ID: mdl-4011615

ABSTRACT

Circadian fluctuation in the spatial distribution of immature Culicoides variipennis (Coq.) was studied in Saltville, Virginia, USA during the summer of 1983. Pupae and early instar larvae (1st and 2nd) were localized above the shoreline in the top cm of mud and displayed little migration from this region during the 24 hr sampling period, however, later instar larvae (3rd and 4th) showed marked migration patterns. Most larval movement was horizontal rather than vertical and was confined to the top cm of mud. Late instar larvae moved towards the water during the day but migrated up above shoreline during the night. Seasonal fluctuation in larval spatial distribution was also studied. Larvae appeared to move progressively downward into the mud during the autumn. However, when the site became frozen the majority of larvae occupied a narrow liquid interface between the ice cover and the frozen mud beneath.


Subject(s)
Ceratopogonidae/physiology , Animals , Ecology , Larva , Seasons , Time Factors , Virginia
17.
Poult Sci ; 60(3): 556-62, 1981 Mar.
Article in English | MEDLINE | ID: mdl-7301725

ABSTRACT

Field trials were conducted in 1974 and 1975 using an encapsulated formulation of methoprene (AltosidTM) applied as a feed additive at rates of 7.5 and 10.0 ppm (AI in feed) to control Musca domestica L. in poultry houses. Only limited inhibition of house fly emergence was obtained. In addition, the percentage of house fly emergence in each trial gradually increased as the season progressed. Comparison bioassays were conducted at the end of the 1975 season between field-pressured strains and lab-reared susceptible strains. Results from the field trials and comparison bioassays indicated that the causes of the poor inhibition were an existing cross-resistance to methoprene followed by an induction of resistance resulting from the continuous exposure to methoprene.


Subject(s)
Chickens , Houseflies/drug effects , Juvenile Hormones/administration & dosage , Methoprene/administration & dosage , Animal Feed , Animals , Housing, Animal
19.
Poult Sci ; 57(6): 1728-32, 1978 Nov.
Article in English | MEDLINE | ID: mdl-751046

ABSTRACT

Roosters from a line artificially selected for high initial antibody response to sheep red blood cells were more resistant to development of populations of Ornitbonyssus sylviarum (Canestrini and Fanzago) than were birds selected for low antibody response. Oral administration of corticosterone to test chickens at doses ranging from 10 to 40 ppm did not affect mite development. The steroid regimen was shown to reduce lymphocyte and testes mass as well as total weight gain. Postmortem measurements were not different for the 2 inbred lines. Analysis of data indicated that antibody competency alone probably was not responsbile for the observed differences in mite populations.


Subject(s)
Antibody Formation , Chickens/immunology , Corticosterone/pharmacology , Mite Infestations/veterinary , Poultry Diseases/immunology , Animals , Antibody Formation/drug effects , Chickens/genetics , Male , Mite Infestations/immunology , Selection, Genetic
20.
Poult Sci ; 57(4): 1088-90, 1978 Jul.
Article in English | MEDLINE | ID: mdl-674069

ABSTRACT

Treatment of normal male Leghorn chickens with doses of estradiol ranging from .1 to 1.0 mg per week caused only a slight increase in resistance to infestation with northern fowl mites. The resistance phenomenon did not increase linearly with estradiol dose. Pullets were initially resistant to mite infestation; however, susceptibility was noted to increase markedly near the time of initial egg-production. These data indicate that sex hormones may be related to mite resistance in chickens, but that estrogen alone is probably not responsible for the difference in mite susceptibility between male and female birds.


Subject(s)
Chickens , Estradiol Congeners/pharmacology , Estradiol/pharmacology , Mite Infestations/veterinary , Oviposition , Poultry Diseases/physiopathology , Animals , Female , Male , Mite Infestations/physiopathology , Sexual Maturation
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