The relationship between pathogen life history traits and metapopulation dynamics

Hosts diverge widely in how, and how well, they defend themselves against infection and immunopathology. Why are hosts so heterogeneous? Both epidemiology and life history are commonly hypothesized to influence host immune strategy, but the relationship between immune strategy and each factor has commonly been investigated in isolation. Here, we show that interactions between life history and epidemiology are crucial for determining optimal immune specificity and sensitivity. We propose a demographically-structured population dynamics model, in which we explore sensitivity and specificity of immune responses when epidemiological risks vary with age. We find that variation in life history traits associated with both reproduction and longevity alters optimal immune strategies–but the magnitude and sometimes even direction of these effects depends on how epidemiological risks vary across life. An especially compelling example that explains previously-puzzling empirical observations is that depending on whether infection risk declines or rises at reproductive maturity, later reproductive maturity can select for either greater or lower immune specificity, potentially illustrating why studies of lifespan and immune variation across taxa have been inconclusive. Thus, the sign of selection on the life history-immune specificity relationship can be reversed in different epidemiological contexts. Drawing on published life history data from a variety of chordate taxa, we generate testable predictions for this facet of the optimal immune strategy. Our results shed light on the causes of the heterogeneity found in immune defenses both within and among species and the ultimate variability of the relationship between life history and immune specificity.

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Capture technique and fish personality: angling targets timid bluegill sunfish, Lepomis macrochirus

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f2011-019 ◽

2011 ◽

Vol 68 (5) ◽

pp. 749-757 ◽

Cited By ~ 80

Author(s):

Alexander D.M. Wilson ◽

Thomas R. Binder ◽

Keegan P. McGrath ◽

Steven J. Cooke ◽

Jean-Guy J. Godin

Keyword(s):

Life History ◽

Individual Differences ◽

Life History Traits ◽

Lepomis Macrochirus ◽

Open Water ◽

Wild Fish ◽

Bluegill Sunfish ◽

In The Wild ◽

The Relationship ◽

Capture Technique

Size-selective harvesting associated with commercial and recreational fishing practices has been shown to alter life history traits through a phenomenon known as fishing-induced evolution. This phenomenon may be a result of selection pathways targeting life-history traits directly or indirectly through correlations with behavioral traits. Here, we report on the relationship between individual differences in behavior and capture technique (beach seining versus angling) in wild-caught juvenile bluegill sunfish ( Lepomis macrochirus ). Both fish caught by using a seine net (seined) and fish caught by using a lure (angled) were individually tested under standardized laboratory conditions for their boldness, water-column use, and general activity. Observed inter-individual differences in boldness were strongly correlated with method of capture in the wild. Fish caught by angling were more timid and had fewer ectoparasites than fish caught using a seine net. However, this relationship did not carry over to an experiment in a large outdoor pool with seine-caught, individually tagged wild fish, where bolder individuals were more likely to be angled in open water away from refuges than more timid individuals, based on their previously assessed boldness scores. Our study is both novel and important, as it describes the relationship between capture technique and boldness in a natural population and underscores the potential risk of sampling biases associated with method of animal capture for behavioral, population, and conservation biologists.

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The Relationship between Diaspore Characteristics with Phylogeny, Life History Traits, and Their Ecological Adaptation of 150 Species from the Cold Desert of Northwest China

The Scientific World JOURNAL ◽

10.1155/2014/510343 ◽

2014 ◽

Vol 2014 ◽

pp. 1-19 ◽

Cited By ~ 2

Author(s):

Hui-Liang Liu ◽

Dao-Yuan Zhang ◽

Shi-Min Duan ◽

Xi-Yong Wang ◽

Ming-Fang Song

Keyword(s):

Life History ◽

Life History Traits ◽

Northwest China ◽

Biological Characteristics ◽

Ecological Adaptation ◽

Gurbantunggut Desert ◽

Cold Desert ◽

Dispersal Syndromes ◽

Gurbantünggüt Desert ◽

The Relationship

Diaspore characteristics of 22 families, including 102 genera and 150 species (55 represented by seeds and 95 by fruits) from the Gurbantunggut Desert were analyzed for diaspore biological characteristics (mass, shape, color, and appendage type). The diaspore mass and shape were significantly different in phylogeny group (APG) and dispersal syndromes; vegetative periods significantly affected diaspore mass, but not diaspore shape; and ecotypes did not significantly affect diaspore mass and shape, but xerophyte species had larger diaspore mass than mesophyte species. Unique stepwise ANOVA results showed that variance in diaspore mass and shape among these 150 species was largely dependent upon phylogeny and dispersal syndromes. Therefore, it was suggested that phylogeny may constrain diaspore mass, and as dispersal syndromes may be related to phylogeny, they also constrained diaspore mass and shape. Diaspores of 85 species (56.67%) had appendages, including 26 with wings/bracts, 18 with pappus/hair, 14 with hooks/spines, 10 with awns, and 17 with other types of appendages. Different traits (mass, shape, color, appendage, and dispersal syndromes) of diaspore decided plants forming different adapted strategies in the desert. In summary, the diaspore characteristics were closely related with phylogeny, vegetative periods, dispersal syndromes, and ecotype, and these characteristics allowed the plants to adapt to extreme desert environments.

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Duration of snow cover and its influence on life-history variation in yellow-bellied marmots

Canadian Journal of Zoology ◽

10.1139/z91-244 ◽

1991 ◽

Vol 69 (7) ◽

pp. 1755-1758 ◽

Cited By ~ 68

Author(s):

Dirk Van Vuren ◽

Kenneth B. Armitage

Keyword(s):

Life History ◽

Snow Cover ◽

Life History Traits ◽

Growing Season ◽

Snow Melt ◽

Life History Variation ◽

Intrapopulation Variation ◽

Young Of The Year ◽

Access To Food ◽

The Relationship

We evaluated the relationship between growing-season phenology, as indicated by time of snow melt, and intrapopulation variation in reproduction and growth of yellow-bellied marmots. The time of snow melt explained significant proportions of the variation in frequency of reproduction (78%), litter size (79%), and estimated body mass of young of the year (68%), but not growth rate. We suggest that the duration of snow cover, through its effect on the length of the growing season, influences habitat quality; marmots living at localities with prolonged snow cover have a shorter season of access to food. The variation in life-history traits is attributed to phenotypic plasticity and not to local genetic variation.

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Urban tolerance of birds changes throughout the full annual cycle

10.32942/osf.io/9m8wj ◽

2021 ◽

Author(s):

Corey Thomas Callaghan ◽

William Kirkham Cornwell ◽

Ailstair G. B. Poore ◽

Yanina ◽

Federico Morelli

Keyword(s):

Life History ◽

Annual Cycle ◽

Life History Traits ◽

Linear Models ◽

Bird Species ◽

Breeding Period ◽

Continuous Measure ◽

Night Time ◽

Annual Variability ◽

The Relationship

Aim: Our objective was to quantify urban tolerance for North American birds across the full annual cycle. We tested (1) whether intra-annual variability of urban tolerance differed between migrants and residents and (2) whether intra-annual variability of urban tolerance was phylogenetically conserved. We then assessed how the relationship between ecological and life history traits and urban tolerance differed both across the year and between migrants and residents.Location: North America.Taxon: Birds.Methods: We integrated a large citizen science dataset of observations for 237 bird species, remotely-sensed VIIRS night-time lights data, and trait data on each species. We estimate, for each species and each month of the year, a continuous measure of urban tolerance (i.e. the median of their distribution of observations across an urbanization gradient). We then use phylogenetic linear models to assess the relationship between this measure of urban tolerance and various life history and ecological traits.Results: There was a distinct drop in the overall urban tolerance scores corresponding with the breeding period; this pattern was more pronounced for migrants compared to residents. Migrants also had greater intra-annual variability than resident species. We also found that the strength of the relationships between ecological and life history traits and urban tolerance was highly seasonal for most traits considered, and some divergent patterns were noted between migrants and residents. Main conclusions: The urban tolerance of birds greatly changed throughout the annual cycle, with different patterns for migrants and residents. Compared to residents, migrants showed more intra-annual variability of urban tolerance with a drop in the average urban tolerance score during the breeding season. Together, our results suggest that urban tolerance is a function of both species and season, and they highlight the importance of considering the dynamic nature of birds’ use of urban ecosystems throughout the full annual cycle.

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Life history traits and ecological conditions influencing the symbiotic relationship between the flatworm Stylochoplana pusilla and host snail Monodonta labio

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315415001009 ◽

2015 ◽

pp. 1-6

Author(s):

Yuta Fujiwara ◽

Tomoya Iwata ◽

Jotaro Urabe ◽

Satoshi Takeda

Keyword(s):

Growth Rate ◽

Life History ◽

Life History Traits ◽

Isotope Analysis ◽

Survival Rates ◽

Mantle Cavity ◽

Tide Pool ◽

Host Snail ◽

Juvenile Stages ◽

The Relationship

Clarification of the life-history traits of a symbiont and its host is necessary to evaluate the relationship between them.Stylochoplana pusilla, a polyclad, inhabits the mantle cavity of the eulittoral snailMonodonta labio. This study elucidated the life-history traits ofS. pusillarelative to those ofM. labioin a tide pool, which retained seawater, and a boulder shore, which was dry at low tide, in Mutsu Bay, northern Japan, from 2010 to 2012. In these habitats,S. pusillawas semelparous with a 1-year life cycle; it reproduced in midsummer and inhabited the shell ofM. labioexcept for the early juvenile stages, which were planktonic. More juvenileS. pusillanewly settled on hosts in the tide pool than on the boulder shore, however, their survival rate was higher on the boulder shore compared with the tide pool. The growth rate of juvenileS. pusillawas higher in the tide pool than on the boulder shore. The higher growth rate ofS. pusillaat the tide pool suggested that they were more actively feeding. Stable isotope analysis showed thatS. pusillaacquired food resources outside the host snail both in the tide pool and on the boulder shore. Thus, it was likely thatS. pusillaengaged in feeding outside the host snails but resulted in lower survival rates at the tide pool. These results suggest thatS. pusillais semi-free living and usesM. labioas a refuge in the eulittoral zone for protection against desiccation.

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Lifetime cancer prevalence and life history traits in mammals

Evolution Medicine and Public Health ◽

10.1093/emph/eoaa015 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 187-195 ◽

Cited By ~ 6

Author(s):

Amy M Boddy ◽

Lisa M Abegglen ◽

Allan P Pessier ◽

Athena Aktipis ◽

Joshua D Schiffman ◽

...

Keyword(s):

Life History ◽

Litter Size ◽

San Diego ◽

Life History Theory ◽

Life History Traits ◽

Mammalian Species ◽

Cancer Prevalence ◽

Trade Offs ◽

Common Diagnosis ◽

The Relationship

Abstract Background Cancer is a common diagnosis in many mammalian species, yet they vary in their vulnerability to cancer. The factors driving this variation are unknown, but life history theory offers potential explanations to why cancer defense mechanisms are not equal across species. Methodology Here we report the prevalence of neoplasia and malignancy in 37 mammalian species, representing 11 mammalian orders, using 42 years of well curated necropsy data from the San Diego Zoo and San Diego Zoo Safari Park. We collected data on life history components of these species and tested for associations between life history traits and both neoplasia and malignancy, while controlling for phylogenetic history. Results These results support Peto’s paradox, in that we find no association between lifespan and/or body mass and the prevalence of neoplasia or malignancy. However, a positive relationship exists between litter size and prevalence of malignancy (P = 0.005, Adj. R2 = 0.212), suggesting that a species’ life history strategy may influence cancer vulnerabilities. Lastly, we tested for the relationship between placental invasiveness and malignancy. We find no evidence for an association between placental depth and malignancy prevalence (P = 0.618, Adj. R2 = 0.068). Conclusions Life history theory offers a powerful framework to understand variation in cancer defenses across the tree of life. These findings provide insight into the relationship between life history traits and cancer vulnerabilities, which suggest a trade-off between reproduction and cancer defenses. Lay summary Why are some mammals more vulnerable to cancer than others? We test whether life history trade-offs may explain this variation in cancer risk. Bigger, longer-lived animals do not develop more cancer compared to smaller, shorter-lived animals. However, we find a positive association between litter size and cancer prevalence in mammals.

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