Early swelling response to phytohemagglutinin is lower in older toads

The effects of age on performance of life-history traits are diverse, but a common outcome is senescence, an irreversible deterioration of physical and physiological capabilities of older individuals. Immune response is potentially bound to senescence. However, little is known about immune response ageing in amphibians. In this work, we test the hypothesis that amphibian early immune response is reduced in older individuals. To this end, we captured adult natterjack toads (Epidalea calamita) and inoculated them with phytohemagglutinin, an innocuous protein that triggers a skin-swelling immune response whose magnitude is directly proportional to the ability of the individual to mount an immune response. We measured early swelling immune response (corresponding to an innate-response stage) hourly, for six hours, and we calculated the area under the curve (AUC) for each individual’s time series, as a measure of immune response magnitude incorporating time. We estimated toad age by means of phalanx skeletochronology. Swelling and AUC decreased with age. Therefore, in accordance with our predictions, early immune response seems subject to senescence in these toads. Reduced ability to get over infections due to senescence of immune respose might be—together with a worse functioning of other organs and systems—among the causes of lower survival of older specimens.

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Individual variability in life-history traits drives population size stability

Current Zoology ◽

10.1093/czoolo/58.2.358 ◽

2012 ◽

Vol 58 (2) ◽

pp. 358-362 ◽

Cited By ~ 6

Author(s):

Ned A. Dochtermann ◽

C. M. Gienger

Keyword(s):

Life History ◽

Life History Traits ◽

Individual Variability ◽

Population Variation ◽

Sceloporus Undulatus ◽

Natural Systems ◽

Size Stability ◽

Population Sizes ◽

The Individual ◽

Dynamics Of Populations

Abstract Understanding how population sizes vary over time is a key aspect of ecological research. Unfortunately, our understanding of population dynamics has historically been based on an assumption that individuals are identical with homogenous life-history properties. This assumption is certainly false for most natural systems, raising the question of what role individual variation plays in the dynamics of populations. While there has been an increase of interest regarding the effects of within population variation on the dynamics of single populations, there has been little study of the effects of differences in within population variation on patterns observed across populations. We found that life-history differences (clutch size) among individuals explained the majority of the variation observed in the degree to which population sizes of eastern fence lizards Sceloporus undulatus fluctuated. This finding suggests that differences across populations cannot be understood without an examination of differences at the level of a system rather than at the level of the individual [Current Zoology 58 (2): 358–362, 2012].

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Detrimental impacts of toxic Microcystis aeruginosa from Vietnam on life history traits of Daphnia magna

Journal of Vietnamese Environment ◽

10.13141/jve.vol8.no1.pp56-61 ◽

2016 ◽

Vol 8 (1) ◽

pp. 56-61

Author(s):

Thi My Chi Vo ◽

Thanh Luu Pham ◽

Thanh Son Dao

Keyword(s):

Life History ◽

Daphnia Magna ◽

Microcystis Aeruginosa ◽

Life History Traits ◽

Scientific Information ◽

Reproductive Age ◽

Viet Nam ◽

Negative Effects ◽

The Individual ◽

Population Rate

In this study, we tested the long-term and negative effects of microcystin-producing cyanobacterium Microcystis aeruginosa from Vietnam on Daphnia magna under the laboratory conditions. The test organisms were fed with mixtures of green alga Scenedesmus armatus and toxic M. aeruginosa at different ratios (10% Microcystis + 90% Scenedesmus, 50% Microcystis + 50% Scenedesmus, 100% Microcystis, and 100% Scenedesmus) for over a period of 21 days. The life history traits of the organisms such as, survival, maturation, fecundity were daily recorded. Besides, the intrinsic population rate of D. magna in each treatment was also calculated based on the survivorship, the reproductive age and the clutch size of the animals. The results showed that survival, maturation and reproduction of the D. magna fed with 10, 50 and 100% M. aeruginosa was impaired. Additionally, the intrinsic population rate of the exposed D. magna was lower than that of the control. This study evidenced the adverse effects of toxic M. aeruginosa on both the individual and intrinsic population levels of D. magna. To our knowledge, this is the first report on the chronically detrimental impacts of toxic M. aeruginosa isolated from Vietnam on D. magna and contributed the scientific information on the severe influences of toxic cyanobacteria world wide. Trong bài viết này, chúng tôi nghiên cứu ảnh hưởng xấu mãn tính của loài vi khuẩn lam Microcystis aeruginosa có khả năng sản sinh độc tố microcysin từ Việt Nam lên Daphnia magna trong điều kiện phòng thí nghiệm. Sinh vật thí nghiệm được cho ăn với hỗn hợp tảo lục Scenedesmus armatus và M. aeruginosa có độc ở các tỷ lệ khác nhau (10% Microcystis + 90% Scenedesmus, 50% Microcystis + 50% Scenedesmus, 100% Microcystis, và 100% Scenedesmus) trong thời gian 21 ngày. Các đặc điểm vòng đời của sinh vật bao gồm sức sống, sự thành thục, sức sinh sản được theo dõi hàng ngày. Bên cạnh đó, tỷ lệ phát triển quần thể của D. magna trong từng lô thí nghiệm cũng được tính toán dựa vào sức sống, tuổi sinh sản và kích cỡ sinh sản của sinh vật. Kết quả cho thấy, sức sống, tuổi thành thục và sự sinh sản của D. magna cho ăn với 10, 50 và 100% M. aeruginosa bị ảnh hưởng xấu. Bên cạnh đó, tỷ lệ phát triển quần thể của D. magna trong lô phơi nhiễm thấp hơn so với đối chứng. Nghiên cứu này chứng minh ảnh hưởng xấu của M. aeruginosa có độc lên cả hai mức độ cá thể và quần thể của D. magna. Theo hiểu biết của chúng tôi, đây là báo cáo đầu tiên về ảnh hưởng xấu mãn tính của M. aeruginosa có độc phân lập từ Việt Nam lên D. magna and đóng góp thêm thông tin khoa học cho những ảnh hưởng nghiêm trọng của vi khuẩn lam có độc trên khắp thế giới.

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Sympatric versus allopatric evolutionary contexts shape differential immune response in Biomphalaria / Schistosoma interaction

10.1101/378034 ◽

2018 ◽

Author(s):

Anaïs Portet ◽

Silvain Pinaud ◽

Cristian Chaparro ◽

Richard Galinier ◽

Nolwenn M. Dheilly ◽

...

Keyword(s):

Immune Response ◽

Life History ◽

Schistosoma Mansoni ◽

Local Adaptation ◽

Cellular Response ◽

Life History Traits ◽

Immune Cell ◽

Helminth Parasites ◽

Geographic Variations ◽

Host Parasite

AbstractSelective pressures between hosts and their parasites can result in reciprocal evolution or adaptation of specific life history traits. Local adaptation of resident hosts and parasites should lead to increase parasite infectivity/virulence (higher compatibility) when infecting hosts from the same location (in sympatry) than from a foreign location (in allopatry). Analysis of geographic variations in compatibility phenotypes is the most common proxy used to infer local adaptation. However, in some cases, allopatric host-parasite systems demonstrate similar or greater compatibility than in sympatry. In such cases, the potential for local adaptation remains unclear. Here, we study the interaction between Schistosoma and its vector snail Biomphalaria in which such discrepancy in local versus foreign compatibility phenotype has been reported. Herein, we aim at bridging this gap of knowledge by comparing life history traits (immune cellular response, host mortality, and parasite growth) and molecular responses in highly compatible sympatric and allopatric Schistosoma/Biomphalaria interactions originating from different geographic localities (Brazil, Venezuela and Burundi). We found that despite displaying similar prevalence phenotypes, sympatric schistosomes triggered a rapid immune suppression (dual-RNAseq analyses) in the snails within 24h post infection, whereas infection by allopatric schistosomes (regardless of the species) was associated with immune cell proliferation and triggered a non-specific generalized immune response after 96h. We observed that, sympatric schistosomes grow more rapidly. Finally, we identify miRNAs differentially expressed by Schistosoma mansoni that target host immune genes and could be responsible for hijacking the host immune response during the sympatric interaction. We show that despite having similar prevalence phenotypes, sympatric and allopatric snail-Schistosoma interactions displayed strong differences in their immunobiological molecular dialogue. Understanding the mechanisms allowing parasites to adapt rapidly and efficiently to new hosts is critical to control disease emergence and risks of Schistosomiasis outbreaks.Author summarySchistosomiasis, the second most widespread human parasitic disease after malaria, is caused by helminth parasites of the genus Schistosoma. More than 200 million people in 74 countries suffer from the pathological, and societal consequences of this disease. To complete its life cycle, the parasite requires an intermediate host, a freshwater snail of the genus Biomphalaria for its transmission. Given the limited options for treating Schistosoma mansoni infections in humans, much research has focused on developing methods to control transmission by its intermediate snail host. Biomphalaria glabrata. Comparative studies have shown that infection of the snail triggers complex cellular and humoral immune responses resulting in significant variations in parasite infectivity and snail susceptibility, known as the so-called polymorphism of compatibility. However, studies have mostly focused on characterizing the immunobiological mechanisms in sympatric interactions. Herein we used a combination of molecular and phenotypic approaches to compare the effect of infection in various sympatric and allopatric evolutionary contexts, allowing us to better understand the mechanisms of host-parasite local adaptation. Learning more about the immunobiological interactions between B. glabrata and S. mansoni could have important socioeconomic and public health impacts by changing the way we attempt to eradicate parasitic diseases and prevent or control schistosomiasis in the field.

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Mind the gap: extending the conceptual model of river island development to different environmental conditions and tree species

10.5194/egusphere-egu21-1588 ◽

2021 ◽

Author(s):

Walter Bertoldi ◽

Angela M. Gurnell

Keyword(s):

Time Series ◽

Life History ◽

Conceptual Model ◽

Life History Traits ◽

Aerial Images ◽

Alnus Incana ◽

Field Observations ◽

Flood Disturbance ◽

Tagliamento River ◽

Growing Conditions

We present recent results of field observations on an island braided reach of the middle Tagliamento River, Italy, where riparian vegetation survival and establishment depends on an unstable balance between vegetation growth and flood disturbance. We combined field observations and information extracted from aerial images, airborne lidar data, and river flow time series for the period 1986-2017 to investigate the changing spatial distribution of woody vegetation and the associated changes in river topography. We also explored the role of Alnus incana (a member of the Betulaceae family), in an environment dominated by the Salicaceae family (e.g. Populus nigra).We observed that gaps between established islands and/or floodplain offer shelter to vegetation, supporting higher colonisation success and different vegetation-landform evolution pathways.In particular, A. incana predominantly grows in lines along channel, island and floodplain edges, bordering wooded areas dominated by P. nigra. Given their association with floodplain and island edges and the relationship of taller (older) trees with more elevated surfaces, A. incana in the study reach appears to complement the physical engineering of the dominant species, P. nigra. This suggests that P. nigra may facilitate colonisation by alder but then both species trap sediments to aggrade channel edges and bar surfaces and build island and floodplain landforms.Time sequences of aerial images in combination with the flood disturbance time series allowed us to interpret vegetation dynamics and to identify the fate of sexual and asexual reproduction strategies by observing vegetation expansion from lines of young plants and shrubs and from uprooted deposited trees and pioneer islands, respectively. Field observations are then generalized to extend a conceptual model of island development.Growing conditions, disturbance energy, and time (window of opportunity) between major floods are the main controls on vegetation colonization. These vary among rivers, among reaches along the same river and locally, as in the investigated gaps, allowing different tree species with different life history traits (e.g. Populus nigra, Alnus incana) to engineer local river landforms in different and complementary ways.Although the conceptual model is inspired by observations on the Tagliamento River, consideration of species life history traits and the joint influences of growing conditions, disturbance energy and windows of opportunity provide a framework that may be applied to other temperate rivers where trees drive landform development.

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Estimation of Fitness of Normal and Stylopized Paddy Pest, White Leafhopper Cofana spectra (Distant) (Hemiptera: Cicadellidae), in West Bengal, India through Correlation of Life History Traits

International Journal of Insect Science ◽

10.4137/ijis.s13029 ◽

2014 ◽

Vol 6 ◽

pp. IJIS.S13029

Author(s):

Sangita Mitra ◽

Rupa Harsha ◽

Niladri Hazra ◽

Abhijit Mazumdar

Keyword(s):

Life History ◽

Life History Traits ◽

West Bengal ◽

Principal Component ◽

Relative Importance ◽

Regression Analyses ◽

Morphometric Measurements ◽

History Of ◽

The Difference ◽

The Individual

The assessment of the morphological and reproductive features of white rice leafhopper Cofana spectra (Distant) was carried out using selected characters that bear importance in determining the fitness at the individual and population levels. Morphometric measurements of the individuals reared in the laboratory as normal and stylopized with the strepsipteran parasitoid, Halictophagus australensis Perkins, were recorded and analyzed. A t-test was performed to justify whether parasitization by H. australensis affected the traits. Correlations and regression analyses were carried out to deduce the difference in relative importance of the morphological features in the life history of C. spectra and their variation because of stylopization by H. australensis. A principal component analysis (PCA) was applied on the morphometric data to further substantiate the difference observed in the traits. In case of stylopized white leafhopper (WLH), fecundity was inhibited almost completely irrespective of seasons. The effect of stylopization on the life history traits of C. spectra has been noted that supports its possible use in biocontrol.

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Life-history traits of the spiny dogfish Squalus acanthias in the Adriatic Sea

Scientific Reports ◽

10.1038/s41598-019-50883-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Giada Bargione ◽

Fortunata Donato ◽

Mario La Mesa ◽

Carlotta Mazzoldi ◽

Emilio Riginella ◽

...

Keyword(s):

Life History ◽

Life History Traits ◽

Adriatic Sea ◽

Growth Parameters ◽

Sampling Period ◽

Squalus Acanthias ◽

Spiny Dogfish ◽

The North ◽

Size At Sexual Maturity ◽

The Individual

Abstract Pivotal life history traits concerning age structure and reproduction of the spiny dogfish (Squalus acanthias, Linnaeus 1758) were investigated in the Adriatic Sea from mid February 2012 to mid July 2013 and in 2016. The whole sample consisted of 176 females and 150 males, ranging between 217–1025 mm and 219–875 mm, respectively. The individual age, which was estimated using a cross-sectioning technique of the second dorsal-fin spine, ranged from 0 to 13+ years for females and from 0 to 9+ years for males. Based on the length-at-age estimates, the Gompertz growth parameters were L∞ = 1130 mm, k = 0.18 and L∞ = 920 mm, k = 0.24 for females and males, respectively. The size at sexual maturity (L50) was 659 mm for females and 575 mm for males, corresponding to 7.5 and 5.5 years of age (A50), respectively. Mean biennial fecundity was approximately 11 embryos/female and 12 ripe oocytes/female. Mature males occurred during much of the sampling period, while mature females with nearly full-term embryos were exclusively recorded in May 2013 and July 2016. Monitoring of catches conducted in a sample port of the north Adriatic (Chioggia) over the past 20 years has shown fluctuating trends in landings, with peaks during the summer reproductive season.

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Linking the performance of a data-limited empirical catch rule to life-history traits

ICES Journal of Marine Science ◽

10.1093/icesjms/fsaa054 ◽

2020 ◽

Vol 77 (5) ◽

pp. 1914-1926

Author(s):

Simon H Fischer ◽

José A A De Oliveira ◽

Laurence T Kell

Keyword(s):

Time Series ◽

Life History ◽

Life Histories ◽

Life History Traits ◽

Growth Parameter ◽

Reference Points ◽

Total Allowable Catch ◽

Fish Stocks ◽

Wide Range ◽

Spawning Stock

Abstract Worldwide, the majorities of fish stocks are data-limited and lack fully quantitative stock assessments. Within ICES, such data-limited stocks are currently managed by setting total allowable catch without the use of target reference points. To ensure that such advice is precautionary, we used management strategy evaluation to evaluate an empirical rule that bases catch advice on recent catches, information from a biomass survey index, catch length frequencies, and MSY reference point proxies. Twenty-nine fish stocks were simulated covering a wide range of life histories. The performance of the rule varied substantially between stocks, and the risk of breaching limit reference points was inversely correlated to the von Bertalanffy growth parameter k. Stocks with k>0.32 year−1 had a high probability of stock collapse. A time series cluster analysis revealed four types of dynamics, i.e. groups with similar terminal spawning stock biomass (collapsed, BMSY, 2BMSY, 3BMSY). It was shown that a single generic catch rule cannot be applied across all life histories, and management should instead be linked to life-history traits, and in particular, the nature of the time series of stock metrics. The lessons learnt can help future work to shape scientific research into data-limited fisheries management and to ensure that fisheries are MSY compliant and precautionary.

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Dynamics of Weeds in the Soil Seed Bank: A Hidden Markov Model to Estimate Life History Traits from Standing Plant Time Series

PLoS ONE ◽

10.1371/journal.pone.0139278 ◽

2015 ◽

Vol 10 (10) ◽

pp. e0139278 ◽

Cited By ~ 10

Author(s):

Benjamin Borgy ◽

Xavier Reboud ◽

Nathalie Peyrard ◽

Régis Sabbadin ◽

Sabrina Gaba

Keyword(s):

Time Series ◽

Life History ◽

Markov Model ◽

Hidden Markov Model ◽

Seed Bank ◽

Life History Traits ◽

Hidden Markov ◽

Soil Seed Bank

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Impact of density and sex-dependent larval competition on selected life history traits ofDrosophila melanogaster(Diptera: Drosophilidae)

The Canadian Entomologist ◽

10.4039/tce.2017.56 ◽

2017 ◽

Vol 150 (1) ◽

pp. 87-99

Author(s):

Sohini Singha Roy ◽

Gautam Aditya ◽

Sujay Ghosh

Keyword(s):

Life History ◽

Life History Traits ◽

Larval Density ◽

Adult Survival ◽

Larval Rearing ◽

Individual Level ◽

Adult Body ◽

Rearing Density ◽

Competitive Behaviour ◽

The Individual

AbstractAn assessment of the effects of competitive behaviour and sex on seven selected life history traits ofDrosophila melanogasterMeigen (Diptera: Drosophilidae) was made under precisely regulated larval density. Contrary to the conditions of crowding, as considered in many previous studies, the low scale of density enabled assessment of the life history traits at the individual level with higher precision and low variations. The 0-day-old first instars were reared with the relative density of 1,2, 3, and 4 individuals with optimal food until the adults emerged. The life history traits like age at pupation, age at eclosion, adult body weight, adult body length, wing length, and adult survival were used as response variables. Both the density and sex of the competitors were considered as predictors of the life history traits and a stronger effect was evident in the female sex than in males, which is statistically significant. Result also revealed the effect of competitive behaviour was more intense in case of same sex competitors than of opposite sex. In all instances, the life history traits exhibited a trend of decreasing function with the increasing larval rearing density, in compliance with the norms of density-dependent effects on development ofDrosophilaFallén and similar insects.

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