Demographic responses of Virginia opossums to limitation at their northern boundary

2004 ◽  
Vol 82 (7) ◽  
pp. 1126-1134 ◽  
Author(s):  
L Leann Kanda ◽  
Todd K Fuller
Keyword(s):  
Life History ◽  
Survival Rate ◽  
Demographic Data ◽  
Survival Rates ◽  
Life History Strategy ◽  
Didelphis Virginiana ◽  
Winter Survival ◽  
Life History Strategies ◽  
Physiological Limit ◽  
Virginia Opossum

The precise response of a population at its distributional edge to the limiting extrinsic factor should be mediated by the demography of the species. We applied this principle to understanding the northern distributional potential of the Virginia opossum (Didelphis virginiana Kerr, 1792). We reviewed the literature for demographic data that we then used to build model populations. Juvenile over-winter survival was adjusted to determine the survival necessary for a stable population. To put the results in the context of life-history strategy and ecological niche, we built models for two other medium-sized mammals with similar distributions, the raccoon (Procyon lotor (L., 1758)) and the muskrat (Ondatra zibethicus (L., 1766)). Northern raccoon populations may sustain juvenile winter survival rates of <0.50 because adult females live to reproduce in multiple years. Muskrat juveniles may need a winter survival rate of only 0.40 in average years because reproduction is very high. In contrast, young northern opossums need a survival rate of 0.81 over winter to compensate for low prewinter survival. Raccoons and muskrats, through different life-history strategies, should be able to expand their northern distribution to the winter-induced physiological limit. However, opossum populations should fail before the average individual physiological limit is reached.

Effect of time of day, time of year, and life history strategy on time budgeting in juvenile Atlantic salmon, Salmo salar

1999 ◽  
Vol 56 (12) ◽  
pp. 2397-2403 ◽  
Author(s):  
Sveinn K Valdimarsson ◽  
Neil B Metcalfe
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Life History Strategy ◽  
Time Of Day ◽  
Life History Strategies ◽  
Foraging Efficiency ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Time Of Year

Traditionally, behavioural studies on juvenile Atlantic salmon, Salmo salar, have been conducted during the day in summer. It is known that Atlantic salmon become nocturnal in winter, but very little is known about their behaviour at that time. Therefore, observations in a seminatural stream were carried out during the day and night, from February to June, comparing diel and seasonal differences in behaviour between fish adopting alternative life history strategies. The results showed a general trend for more activity in spring than in winter, and the fish were found to be foraging at surprisingly low light levels. There were differences in relative feeding rate between the life history strategies; the early migrant fish foraged mostly during the day whereas the delayed migrant fish did more foraging at night. There is some evidence that the early migrant fish made fewer feeding attempts over the winter, which is surprising, since they grow faster over that period. This suggests differences in foraging efficiency, which could contribute to the separation into these two life history strategies.

Life History Strategies

2018 ◽  
pp. 95-126
Author(s):  
Marco Del Giudice
Keyword(s):  
Life History ◽  
Individual Differences ◽  
Life History Theory ◽  
Human Life ◽  
Life History Strategy ◽  
Current Theory ◽  
Life History Strategies ◽  
Extended Model ◽  
Life History Variation ◽  
Basic Model

The chapter introduces the basics of life history theory, the concept of life history strategy, and the fast–slow continuum of variation. After reviewing applications to animal behavior and physiology, the chapter reviews current theory and evidence on individual differences in humans as manifestations of alternative life history strategies. The chapter first presents a “basic model” of human life history–related traits, then advances an “extended model” that identifies multiple cognitive-behavioral profiles within fast and slow strategies. Specifically, it is proposed that slow strategies comprise prosocial/caregiving and skilled/provisioning profiles, whereas fast strategies comprise antisocial/exploitative and seductive/creative profiles. The chapter also reviews potential neurobiological markers of life history variation and considers key methodological issues in this area.

scholarly journals RETRACTED ARTICLE: Novel life history strategy in a deep sea fish challenges assumptions about reproduction in extreme environments

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Randal A. Singer ◽  
Jon A. Moore ◽  
Edward L. Stanley
Keyword(s):  
Life History ◽  
Deep Sea ◽  
Extreme Environments ◽  
Life History Strategy ◽  
Deep Ocean ◽  
Homogeneous System ◽  
Life History Strategies ◽  
Life History Trait ◽  
Retracted Article ◽  
Sea Fish

Abstract The deep ocean is frequently assumed to be a homogeneous system lacking the same diverse life history strategies found in shallower waters. However, as our methods for exploring the deep ocean improve, common assumptions about dispersal, reproduction and behavior are constantly being challenged. Fishes exhibit the most diverse reproductive strategies among vertebrates. Understanding life history strategies in deep-sea environments is lacking for many species of fishes. Here, we report a novel reproductive strategy where a fish (Parazen pacificus) provides parental care via mouth brooding. This behavior is observed from a specimen collected with eggs present in the buccal cavity, along with other specimens exhibiting pre-brooding morphologies. This is the first description of this unique life history trait in a deep-sea fish and fills in a gap in the larval literature for this family of fishes and prompts further investigation into other novel reproductive modes of deep-sea fauna.

scholarly journals Corticosterone, testosterone and life-history strategies of birds

2010 ◽  
Vol 277 (1697) ◽  
pp. 3203-3212 ◽  
Author(s):  
Michaela Hau ◽  
Robert E. Ricklefs ◽  
Martin Wikelski ◽  
Kelly A. Lee ◽  
Jeffrey D. Brawn
Keyword(s):  
Life History ◽  
Body Mass ◽  
Breeding Season ◽  
Life History Traits ◽  
Survival Rates ◽  
Life History Strategies ◽  
Adult Survival ◽  
Tropical Species ◽  
Published Data ◽  
Season Length

Steroid hormones have similar functions across vertebrates, but circulating concentrations can vary dramatically among species. We examined the hypothesis that variation in titres of corticosterone (Cort) and testosterone (T) is related to life-history traits of avian species. We predicted that Cort would reach higher levels under stress in species with higher annual adult survival rates since Cort is thought to promote physiological and behavioural responses that reduce risk to the individual. Conversely, we predicted that peak T during the breeding season would be higher in short-lived species with high mating effort as this hormone is known to promote male fecundity traits. We quantified circulating hormone concentrations and key life-history traits (annual adult survival rate, breeding season length, body mass) in males of free-living bird species during the breeding season at a temperate site (northern USA) and a tropical site (central Panama). We analysed our original data by themselves, and also combined with published data on passerine birds to enhance sample size. In both approaches, variation in baseline Cort (Cort0) among species was inversely related to breeding season length and body mass. Stress-induced corticosterone (MaxCort) also varied inversely with body mass and, as predicted, also varied positively with annual adult survival rates. Furthermore, species from drier and colder environments exhibited lower MaxCort than mesic and tropical species; T was lowest in species from tropical environments. These findings suggest that Cort0, MaxCort and T modulate key vertebrate life-history responses to the environment, with Cort0 supporting energetically demanding processes, MaxCort promoting survival and T being related to mating success.

scholarly journals Living slow and dying young? Life-history strategy and age-specific survival rates in a precocial small mammal

2004 ◽  
Vol 74 (1) ◽  
pp. 171-180 ◽  
Author(s):  
CORNELIA KRAUS ◽  
DAVID L. THOMSON ◽  
JOACHIM KÜNKELE ◽  
FRITZ TRILLMICH
Keyword(s):  
Life History ◽  
Small Mammal ◽  
Survival Rates ◽  
Life History Strategy ◽  
Young Life

scholarly journals Survival Analysis of Chronic Kidney Disease Patients with Hemodialysis in West Java. Indonesia, Year 2007 - 2018

2020 ◽  
Vol 52 (3) ◽  
pp. 172-179
Author(s):  
Afiatin ◽  
Dwi Agustian ◽  
Kurnia Wahyudi ◽  
Pandu Riono ◽  
Rully M. A. Roesli
Keyword(s):  
Chronic Kidney Disease ◽  
Survival Analysis ◽  
Survival Rate ◽  
Kidney Disease ◽  
Demographic Data ◽  
Survival Rates ◽  
Treatment Quality ◽  
West Java ◽  
Dialysis Treatment ◽  
The Impact

The prevalence of chronic kidney disease on dialysis or CKD5D is increasing with a significant impact on disease burden in many countries. Patients are usually listed in the national renal registries, which report demographic data, incidence, prevalence, and outcome. The survival rate is an important outcome measure to characterize the impact of treatment in the CKD5 patient population in the national and international renal registries. Indonesian Society of Nephrology (InaSN) has the Indonesian Renal Registry program to collect data that was endorsed to monitor dialysis treatment quality in Indonesia. IRR releases an annual report, but there is no survival analysis yet. This study aimed to discover the five-year survival rate of CKD5D patients in West Java between 2007–2018 and its factor based on the IRR database. A retrospective cohort study was performed by gaining all patients' data from the IRR database, then data on all of the patients from West Java province who completed a 5-year follow-up on December 31, 2018. Kaplan-Meier analysis and Cox proportional hazard's model were used to analyze the risk factors. There were 3,199 data included in this study. In total, the 1, 2, 3, 4, and 5 year survival rates are 82%, 70%, 62%, 58%, and 55 %, respectively. Patients whose age is above 55 years and with unknown underlying kidney disease have a worse survival rate with a hazard ratio of 1.28 and 1.50, respectively. Further exploration of IRR data will provide better information on dialysis treatment in Indonesia.

Leadership in dangerous times: Life-history strategy and environmental condition affect preferences for dominant and prestigious leaders

2020 ◽  
Author(s):  
Nan Zhu ◽  
Binbin Chen ◽  
Lei Chang
Keyword(s):  
Life History ◽  
Implicit Association Test ◽  
Life History Strategy ◽  
Relative Strength ◽  
Life History Strategies ◽  
Implicit Association ◽  
Leadership Qualities ◽  
Social Hierarchies ◽  
Strategy Study ◽  
Leadership Preferences

Dominance and prestige, as two distinct status-attaining qualities, are present in modern-day leaders at various levels of social hierarchies to various degrees. From an evolutionary perspective, we speculate that such leadership qualities are implicitly linked to the leadership preferences of followers in the environments where they are more effective or necessary. Moreover, individuals’ life-history strategy might moderate the effect of some contextual factors, such as environmental danger, on leadership preferences of dominant versus prestigious leaders. Three studies tested these hypotheses. In two implicit association test (IAT) experiments, we found that (1) participants implicitly associated danger with dominance, and safety with prestige (Study 1a, N = 32); (2) the relative strength of the implicit association between positive evaluation and prestige is positively correlated with participants’ slow life-history strategy (Study 1b, N = 67). In a third experiment (Study 2, N = 95), self-reported life-history strategy also moderated the effects of experimentally manipulated danger on leadership preferences. The association between dangerous environments and dominant leadership preference was stronger for participants with fast life-history strategies than those with slow life-history strategies.

Physiological Characterization of Hatchery-Origin Juvenile Steelhead Oncorhynchus mykiss Adopting Divergent Life-History Strategies

2011 ◽  
Vol 2 (1) ◽  
pp. 61-71 ◽  
Author(s):  
Kyle C. Hanson ◽  
William L. Gale ◽  
William G. Simpson ◽  
Benjamen M. Kennedy ◽  
Kenneth G. Ostrand
Keyword(s):  
Life History ◽  
Fresh Water ◽  
Gonadosomatic Index ◽  
Life History Strategy ◽  
Life History Strategies ◽  
Migratory Fish ◽  
Physiological Characterization ◽  
Subunit Expression ◽  
Mature Fish

Abstract Smoltification by juvenile Pacific salmonids has been described as a developmental conflict whereby individuals face several life-history decisions. Smoltification occurs as a result of interactions between organismal condition and environmental cues, although some fish may forgo ocean migration and remain in freshwater streams for some time (residualize). We compared the physiological profiles of steelhead that were actively migrating to the ocean (migratory fish) and those that remained in fresh water (residuals) for at least a period of between 2 wk and 3 mo after release from a hatchery facility. In addition, we investigated the physiological characterization of residuals that further differentiated into precocial freshwater residents or parr that will either precocially mature in fresh water or migrate to the ocean in the future. Residuals had higher condition factors and gonadosomatic index than migratory fish and were characterized as less prepared for saltwater due to low levels of gill Na+,K+-ATPase activity and Na+,K+-ATPase α1b-subunit expression. Residuals tended to be males with the highest condition factors. Sex-specific differences are probably reflective of male fish adopting an alternative life-history strategy foregoing outmigration as a result of condition at the time of release. Collection of residuals throughout the fall suggested that residual hatchery fish further diversify into precocially mature fish that will presumably attempt to spawn without ever migrating to the ocean or into parr that will precocially mature or migrate in a future year.

Trait-Based Approach to Fish Ecology

2019 ◽  
pp. 150-160
Author(s):  
Ken H. Andersen
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Life History Strategy ◽  
Somatic Growth ◽  
Population Level ◽  
Historical Background ◽  
Life History Strategies ◽  
Asymptotic Size ◽  
Current State ◽  
Investment In Reproduction

This chapter proposes a shortlist of fish “master” traits and connects these traits to classic life-history strategy thinking. First, it sets the historical background for the current state-of-the-art thinking about fish life history strategies. From there, the chapter explains that the main axes of variation between fish species can be captured by three traits: the asymptotic size; the growth rate coefficient; and the adult–offspring mass ratio strategy. Together, these three traits determine the central demographic parameters: somatic growth rate, investment in reproduction, age at maturation, survival to maturation, mortality, and so on, and from there follows population-level quantities like population growth rate, population structure, fitness, and selection responses. The chapter concludes with a reflection on the trait-based approach and compares it to other methods of assessment.

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