Longevity Data Research Articles

Improving generation length estimates for the IUCN Red List.

The International Union for the Conservation of Nature (IUCN) Red List classifies species according to their risk of extinction, informing local to global conservation decisions. Here we look to advance the estimation of generation length, which is used as a time-scalar in the Red List as a way of accounting for differences in species’ life-histories. We calculated or predicted generation length for 86 species of antelope following the Rspan approach. We also tested the importance of both allometry (body-mass) and phylogeny (phylogenetic eigenvectors) as predictors of generation length within a Phylogenetic Eigenvector Map (PEM) framework. We then evaluated the predictive power of this PEM and two binning approaches, following a leave-one-out cross-validation routine. We showed that captive and wild longevity data are nonequivalent and that both body-mass and phylogeny are important predictors for generation length (body-mass explained 64% and phylogeny 36% of the partitioned explained variance). Plus, both the PEM, and the binning approach that included both taxonomic rank and body-mass, had good predictive power and therefore are suitable for extrapolating generation length to missing-data species. Therefore, based on our findings, we advise separating captive and wild data when estimating generation length, and considering the implications of wild and captive data more widely in life-history analyses. We also recommend that body-mass and phylogeny should be used in combination, preferably under a PEM framework (as it was less reliant on available reference species and more explicitly accounts for phylogenetic relatedness) or a binning approach if a PEM is not feasible, to extrapolate generation length to missing-data species. Overall, we provide a transparent, consistent and transferable workflow for improving the use of the Rspan method to calculate generation length for the IUCN Red List.

Protein Supplementation Principle for Training: Quality is More Important than Quantity

One of the best benefits of exercise training is to increase physical fitness by preserving muscle health against aging. After exercise, regeneration of new cells after muscle damage helps adaptation of the body against new challenge for survival. This recovery process demands carbon and nitrogen sources for reconstructing new cells in the tissue. It is noteworthy that the cell regenerative process during recovery is part of inflammation program (Tidball, 2005), which generates subjective fatigue feeling and pain. Therefore, providing sufficient protein to challenged muscle in time around workout is crucial in preventing fatigue feeling and ensuring fast recovery. To evaluate the quality of dietary protein source should base on its adsorption efficiency, which is more important than the amount of protein provided. There are many dietary sources, which can be used for protein supplementation. Whey protein isolate is generally considered the best source for training individuals. The main reason is that whey protein can be quickly digested and absorbed in human body. Any delay in protein delivery to challenged muscle will prevent fast recovery for regenerating cells. Therefore, supplementation timing is important for optimal training effect in muscle growth. This is particularly important for both the individuals aged above 70 yrs, when muscle loss is the main concern (Esmarck et al., 2001), and the young individuals under sport training (Cribb & Hayes,2006;Levenhagen et al., 2001). Protein is not only important for individuals under exercise training. It is essential for any individual who has high cell proliferation rate, such as during acute illness and fast growing age. However, how much protein should be taken is an important question in human health. Too little protein intake inhibits growth; yet too much protein intake accelerates aging, in particular, increases cancer mortality (Levine et al., 2014). Recommended dietary allowance of 0.75 gram per kilogram body weight according to WHO and 0.8 gram per kilogram body weight according to USDA for those aged older than 19 yrs are considered maximal (National Research Council [US] Subcommittee on the Tenth Edition of the Recommended Dietary Allowances, 1989). These values are not provided based on human longevity data (all-cause mortality), but nitrogen balance outcomes as indirect evidence. Furthermore, high protein supplementation for elderly in the weight falling phase (> 69 years old) shows increased longevity, but the same supplemented quantity for middle-aged individuals in the weight rising phase (50 ~ 65 years old) is associated with shorter longevity (Levine et al., 2014). A lifespan animal study (Solon-Biet et al., 2014) confirms the causal relationship between protein and longevity. In a human training study, ingestion of only 20 g protein for men weighted -- 86 kg is sufficient to maximally stimulate protein synthesis and albumin protein synthesis after resistance exercise (Moore et al., 2009). Similar result has also been reported with approximately the same protein quantity (0.2 g per kg), which can sustain higher protein synthesis rate for at least 5 hrs above fasted condition (Moore et al., 2009). These results clearly indicate that even for someone who challenges the muscle regularly, protein supplementation does not need to supplement to a level suggested by WHO or USDA. Yet, we must stress again that elderly should be considered as different case. For men aged -- 71 yrs, ingestion of 0.4 g per kg is required to maximally stimulate protein synthesis (Moore et al., 2014).

Longevity summary from 69 years of Estrildidae ringing data in southern Africa

This study focuses on the longevity data accumulated for the family Estrildidae, specifically exploring longevity records for each species using ringing data. Longevity is the minimum age reached by an individual as determined by the time elapsed between initial ringing and last recapture or recovery date. In southern Africa bird ringing started in 1948 and is managed by the South African Bird Ringing Scheme. For estrildids, there are 151 831 ringing records. Approximately 7.0% of those ringed individuals have since been resighted, retrapped or recovered. This family is poorly studied and more research is necessary, particularly as certain estrildid species have been highlighted as data-deficient whilst others are potentially of conservation concern. The South African Bird Ringing scheme (SAFRING) has longevity records for 23 of the 27 southern Africa estrildid species. The maximum longevity record was 10.9 years (Blue Waxbill Uraeginthus angolensis). The overall average longevity for an individual is 3.7 years (SD = 2.5). The low longevity values make sense given the low mass (6.3–22.7 g) of estrildids. Coupled with large clutch sizes of four eggs on average, as well as potentially low surivival, estrildids may counter low longevity by breeding at an early age and double-brooding.

Effects of short-term heat shock and physiological responses to heat stress in two Bradysia adults, Bradysia odoriphaga and Bradysia difformis

Bradysia odoriphaga and Bradysia difformis are devastating pests of vegetable, ornamental crops and edible mushrooms causing significant losses. Temperature may be an important factor restricting their population abundance in the summer. To determine the effects of short-term heat shock on adults, their survival, longevity and fecundity data were collected, and antioxidant responses and heat shock protein expression levels were examined. Our results indicated that the survival rates of Bradysia adults decreased rapidly after heat shock ≥36 °C, and the longevity and reproductive capacities were significantly inhibited, indicating that short-term heat shock had lethal and sub-lethal effects. Moreover, the lipid peroxidation levels of B. difformis and B. odoriphaga increased dramatically at 36 °C and 38 °C, respectively. Four antioxidant enzymes activities of B. odoriphaga were greater than those of B. difformis at 38 °C. Additionally, hsp70 and hsp90 expression levels significantly increased after heat stress, and higher expression levels of B. difformis and B. odoriphaga were discovered at 36 and 38 °C respectively, indicating their different heat tolerance levels. Overall, short-term heat shock (≥36 °C) caused significantly adverse effects on Bradysia adults, indicating that it could be applied in pest control, and antioxidant system and hsp genes played important roles in their heat tolerance levels.

Technical note: PaGELL v.1.5: A flexible parametric program for the Bayesian analysis of longevity data within the context of animal breeding

This technical note presents the program PaGELL v.1.5 (Parametric Genetic Evaluation of Lifespan in Livestock), a flexible software program to analyze (right-censored) longevity data in livestock populations, with a special emphasis on the genetic evaluation of the breeding stock. This software relies on a parametric generalization of the proportional hazard model; more specifically, the baseline hazard function follows a Weibull process and flexibility is gained by including an additional time-dependent effect with the number of change points defined by the user. The program can accommodate 3 different sources of variation (i.e., systematic, permanent environmental, and additive genetic effects) and both fixed and time-dependent patterns (only for systematic and permanent environmental effects). Analyses are performed within a Bayesian context by sampling from the joint posterior distribution of the model, and model fit can be easily determined by the calculation of the deviance information criterion. Although this software has already been used on field data sets, its performance has been double-checked on simulated data set, and results are presented in this technical note. PaGELL v.1.5 was written in Fortran 95 language and, after compiling with the GNU Fortran Compiler v.4.7 and later, it has been tested in Windows, Linux, and MacOS operating systems (both 32- and 64-bit platforms). This program is available at http://www.casellas.info/files/pageII.zip.

Efficacy of a Targeted Drug Delivery on-Demand Bolus Option for Chronic Pain.

Intrathecal targeted drug delivery systems historically required physician office visits for dose adjustment to manage fluctuating pain. A wireless device now enables patients to supplement their basal intrathecal infusion with a programmed on-demand bolus dose. We sought to quantify the change in oral breakthrough opioid need associated with the use of an intrathecal bolus in comparison to those treated with the basal infusion alone. Demographic, dosage, bolus usage and longevity data were extracted from the historical medical record of 69 patients (18/51 bolus/nonbolus) followed continuously at our center. Medication consumption and Pain Disability Index measures were obtained at baseline and most recent follow-up. Among patients with the bolus option, only 2 (11%; confidence interval [CI] 0% to 26%) continued to require oral opiates to manage breakthrough pain compared to 29 (57%; CI 43% to 71%) without the bolus option. The Pain Disability Index score decreased by 19% in patients with the bolus option and by 25% in those with the basal infusion. Total daily intrathecal opioid intake was 34% lower in the group with the bolus device. Utilizing an intrathecal bolus to treat incident pain was a safe way to manage unpredictable breakthrough pain and may represent a cost-saving opportunity by eliminating the need for oral analgesic medications.

Going beyond life expectancy in assessments of health systems' performance: life expectancy adjusted by perceived health status.

International comparisons of health systems data have been used to guide health policy. Health systems performance is generally evaluated on how different factors contribute to mortality and longevity. Fewer studies scrutinize the factors that determine morbidity in different countries, partly because indicators that assess morbidity on a country level are not as widely available as mortality and longevity data. We introduce a new health status indicator able to combine mortality and morbidity in a single composite measure for each country and gender at a point in time (LEAPHS), yielding the average number of years that men (women) can expect to live in "good" (or better) health. Using the Sullivan method we combine the mortality risk, calculated for specific age and gender groups, with perceived health status for the same age and gender groups, and we estimate how medical care and various socio-economic, environmental and structural, lifestyle, and technological factors affect LEAPHS and life expectancy at birth for a large panel of thirty OECD countries. We find that some variables (alcohol consumption, urbanization) have a significant effect on both LEAPHS and life expectancy, while one variable (the number of hospitals) has a significant effect for both genders on life expectancy only. However, the effects of many other variables (health expenditure per capita, health expenditure per capita squared, GDP growth, and technology) were only significant predictors for LEAPHS. This leads us to conclude that LEAPHS is able to capture the impact of some health determinants not captured by life expectancy at birth. While we believe this new measure may be useful for health economists and statisticians doing cross-country analyses, further comparisons with other measures may be useful.

From den to dust: longevity of three dingoes (Canis lupus dingo) on Fraser Island (K'gari)

The Australian dingo (Canis lupus dingo) is a common and well studied species, yet very little is known about the longevity of free-ranging individuals because most field studies are too short to obtain this information. Fraser Island, off the east coast of Queensland, contains a closed dingo population of high conservation value, and where a portion of them have been captured and subsequently monitored using ear tags and microchips for management purposes since 2002. We use these data to describe the longevity of three individual dingoes, including one female captured, microchipped and ear-tagged as a subadult in February 2003, recaptured and retagged in March 2012, and then found dead in October 2014. Longevity data and other observations demonstrate that wild dingoes can live for at least 13 years and successfully produce litters for at least 10 years. Such life-history data are useful for evaluating the dynamics and stability of dingo populations of conservation concern.

Electrowetting on superhydrophobic natural (Colocasia) and synthetic surfaces based upon fluorinated silica nanoparticles

In this study, we look at alternative coatings to be used in DMF EWOD applications, specifically a natural surface, and synthetic fluorinated silica nanoparticle (FSNP) surfaces. Electrowetting on dielectric (EWOD) is a popular digital microfluidic (DMF) actuation approach, where droplets are moved over a series of electrodes. Hydrophobic coating is required to lower surface friction and enhance droplet movement over the surface. FSNPs are synthesized by a modified Stöber method, with different sizes of nanoparticles (5 to 150nm) and various degrees of fluorination (0 to 90%). These FSNP coatings and natural superhydrophobic surface, Colocasia leaf, were characterized with SEM and tested for their EWOD performance, i.e. EWOD voltage and contact angle change. Colocasia leaf required voltages of >300V for EWOD, whereas the performance of the FSNP coatings with varying nanoparticle sizes and degrees of fluorination show EWOD with voltages as low as 20V. The robustness of the FSNP surfaces was demonstrated by using various organic solvents, and longevity data is also presented.

Backward multiple imputation estimation of the conditional lifetime expectancy function with application to censored human longevity data

The conditional lifetime expectancy function (LEF) is the expected lifetime of a subject given survival past a certain time point and the values of a set of explanatory variables. This function is attractive to researchers because it summarizes the entire residual life distribution and has an easy interpretation compared with the popularly used hazard function. In this paper, we propose a general framework of backward multiple imputation for estimating the conditional LEF and the variance of the estimator in the right-censoring setting. Simulation studies are conducted to investigate the empirical properties of the proposed estimator and the corresponding variance estimator. We demonstrate the method on the Beaver Dam Eye Study data, where the expected human lifetime is modeled with smoothing-spline ANOVA given the covariates information including sex, lifestyle factors, and disease variables.

Tree Mortality in Mature Riparian Forest: Implications for Fremont Cottonwood Conservation in the American Southwest

Abstract. Mature tree mortality rates are poorly documented in desert riparian woodlands. I monitored deaths and calculated annual survivorship probability (Ps) in 2 groups of large (27–114 cm DBH), old (≥40 years old) Fremont cottonwood (Populus fremontii Wats.) in a stand along the free-flowing Yampa River in semiarid northwestern Colorado. Ps = 0.993 year-1 in a group (n = 126) monitored over 2003–2013, whereas Ps = 0.985 year-1 in a group (n = 179) monitored over the same period plus 3 earlier years (2000–2003) that included drought and a defoliating insect outbreak. Assuming Ps was the same for both groups during the 10-year postdrought period, the data indicate that Ps = 0.958 year-1 during the drought. I found no difference in canopy dieback level between male and female survivors. Mortality was equal among size classes, suggesting Ps is independent of age, but published longevity data imply that either Ps eventually declines with age or, as suggested in this study, periods with high Ps are interru...

HRS Expert Consensus Statement on remote interrogation and monitoring for cardiovascular implantable electronic devices.

DavidSlotwiner,MD, FHRS, FACC(Chair),Niraj Varma,MD,PhD, FRCP(Co-chair), JosephG.Akar,MD,PhD, George Annas, JD, MPH, Marianne Beardsall, MN/NP, CCDS, FHRS, Richard I. Fogel, MD, FHRS, Nestor O. Galizio, MD, Taya V. Glotzer, MD, FHRS, FACC, Robin A. Leahy, RN, BSN, CCDS, FHRS, Charles J. Love, MD, CCDS, FHRS, FACC, FAHA, Rhondalyn C. McLean, MD, Suneet Mittal, MD, FHRS, Loredana Morichelli, RN, MSN, Kristen K. Patton, MD, Merritt H. Raitt, MD, FHRS, Renato Pietro Ricci, MD, John Rickard, MD, MPH, Mark H. Schoenfeld, MD, CCDS, FHRS, FACC, FAHA, Gerald A. Serwer, MD, FHRS, FACC, Julie Shea, MS, RNCS, FHRS, CCDS, Paul Varosy, MD, FHRS, FACC, FAHA, Atul Verma, MD, FHRS, FRCPC, Cheuk-Man Yu, MD, FACC, FRCP, FRACP From the Hofstra School of Medicine, North Shore Long Island Jewish Health System, New Hyde Park, New York, Cleveland Clinic, Cleveland, Ohio, Yale University School of Medicine, New Haven, Connecticut, Boston University School of Public Health, Boston, Massachusetts, Southlake Regional Health Centre, Newmarket, Ontario, Canada, St. Vincent Medical Group, Indianapolis, Indiana, Favaloro Foundation University Hospital, Buenos Aires, Argentina, Hackensack University Medical Center, Hackensack, New Jersey, Sanger Heart & Vascular Institute, Carolinas HealthCare System, Charlotte, North Carolina, New York University Langone Medical Center, New York City, New York, University of Pennsylvania Health System, Philadelphia, Pennsylvania, The Arrhythmia Institute at Valley Hospital, New York, New York, Department of Cardiovascular Diseases, San Filippo Neri Hospital, Rome, Italy, University of Washington, Seattle, Washington, VA Portland Health Care System, Oregon Health & Science University, Knight Cardiovascular Institute, Portland, Oregon, Johns Hopkins University, Baltimore, Maryland, Yale University School of Medicine, Yale-New Haven Hospital Saint Raphael Campus, New Haven, Connecticut, University of Michigan Congenital Heart Center, University of Michigan Health Center, Ann Arbor, Michigan, Brigham and Women’s Hospital, Boston, Massachusetts, Veterans Affairs Eastern Colorado Health Care System, University of Colorado, Denver, Colorado, and Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China.

78 * The NHS cannot afford not to implant extended longevity devices to implement the nice guidance on ICD and CRT: modelling the budget impact over 10 years

Introduction: Currently the UK is underpenetrated compared to other developed European countries in terms of implanting cardiac devices, which implies that some eligible patients may not currently be treated. On 25 June 2014, NICE will publish its updated technology appraisal on ICD and CRT and the Final Appraisal Determination (FAD) suggests expanded indications and therefore higher implant rates. Under the NHS Constitution, the guidance will have to be funded by the NHS, but resources are limited. This needs to be resolved. One approach to addressing this is to improve efficiency in the existing system through reducing the number of device replacements due to battery depletion, and use technologies with an increased longevity. Methods & Results: In England, replacement of ICDs and CRT-Ds represent 29% of the total number of procedures. As a result, device longevity (i.e. the number of years the battery is projected to last) is an increasingly important feature of these devices. For patients, the reduction in the number of required interventions has obvious advantages, and for the NHS, there are significant economic savings. A recent study has shown that potential savings of between 29-34% over a 15-year period could be achieved by extending longevity. Based on the methodology from Boriani et al , we have modelled the potential cumulative costs over 10 years for industry-standard and extended longevity battery life devices using real-world battery data for ICDs and CRT-Ds. We used the average longevity described in the NICE FAD (7.1 years for ICD VR and DR,5.8 years for CRT-D), and Boston Scientific real-world longevity data from more than 100,000 ICDs followed in the LATITUDE Patient Management System (13.2 years for ICD VR, 11.5 years for ICD DR, and 9.2 years for CRT-D). Based on 5,589 implant procedures (NHS implants in England in 2012), using devices with extended longevity rather than industry-standard battery longevity could result in potential savings of up to £158 million over 10 years. Based on the current HRG tariff reimbursement of £4,975 per procedure for a cardiac device, and an average device cost of £9,692 (NICE FAD) for an ICD system and £12,293 for a CRT-D system (NICE FAD), this could mean over 9,400 new implants could be funded over a ten-year period. This would significantly increase the number of de novo implants within the NHS, without the need to increase capacity. Conclusion: Up to 70% of patients are now living longer than their de novo devices and are subject to device replacement procedures. Given the impact of such replacements, particularly in light of the financial constraints of the NHS, device longevity is crucial to consider when selecting a device. The NHS would benefit from considering the lifetime cost of the devices in order to make procurement and commissioning decisions.

Limitations of log-rank tests for analysing longevity data in biogerontology.

Log-rank tests are sometimes used to analyse longevity data when other tests should be preferred. When the experimental design involves more than one factor, some authors perform several log-rank tests with the same data, which increases the risk to wrongly conclude that a difference among groups does exist and does not allow to test interactions. When analysing the effect of a single factor with more than two groups, some authors also perform several tests (e.g. comparing a control group to each of the experimental groups), because post hoc analysis is not available with log-rank tests. These errors prevent to fully appreciate the longevity results of these articles and it would be easy to overcome this problem by using statistical methods devoted to one-way or multi-way designs, such as Cox's models, analysis of variance, and generalised linear models.

A test of the metabolic theory of ecology with two longevity data sets reveals no common cause of scaling in biological times

1. The metabolic theory of ecology (MTE) predicts that biological times should universally scale to body mass M as M0.25. However, support for this prediction came principally from non-phylogenetically controlled studies, whereas more recent analyses, which take the degree of shared ancestry between species into account, have revealed that both length of the gestation period and time to first reproduction do not follow this rule. 2. In the present study, we test this prediction of MTE on maximum longevity using two commonly accessible sources of information in zoology and ecology (AnAge and PanTHERIA data bases) that allow us to assess the scaling relation of longevity in more than 1200 mammalian species. We performed our analyses using both ordinary least square (OLS) and phylogenetic generalized least square (PGLS) regressions to assess the importance of controlling for phylogeny in such analyses. 3. Our results revealed clear discrepancies between analyses using the AnAge and PanTHERIA data bases. The scaling of longevity was consistently higher with the PanTHERIA than with the AnAge data base. However, we found that with both data sets, PGLS models performed better than OLS models, and the scaling exponent of longevity is, in nearly all cases, lower than the exponent of 0.25 predicted by the MTE. In addition, we provided evidence that gestation length and longevity do not scale isometrically (i.e. with a scaling exponent of 1.0) with each other as we would expect if these two life history traits had – perhaps due to the same biological principle – the same scaling exponent. 4. Our findings contradict the MTE and suggest that more complex processes than simple relationships with metabolism or body size control the evolution of longevity. Moreover, they reveal differences in relationships of gestation length and longevity that are probably tightly dependent on phylogeny.

How long does the giant saguaro live? Life, death and reproduction in the desert

Little is known about range-wide mortality patterns and reproductive lifetimes of the keystone Carnegiea gigantea (saguaro, Cactaceae) over its range in the Sonoran Desert. The great geographic variability in reproductive effort has been documented, but variation (likely environmentally driven) across populations in life expectancy is relatively unknown, particularly in relation to reproduction over time across populations, the sustainability of populations and their longevity. Longevity is assessed in six populations characterized by different topographic and climatic conditions. Also, longevity data for an amalgamated dataset representing 50,000 km2 of the northern Sonoran Desert are tabulated. I observe that life expectancy is higher in slower growing populations. For example, the cutoff for the oldest 1% of the population ranges from 127 years in the fastest growing population to 193 years of age in the slowest. Past research has shown that more arid (and slow growing) populations delay reproduction and branching (branches increase reproductive output) to much older ages. However, even with significant delays in reproduction, slower-growing populations may still enjoy reproductive lifetimes that are similar to or greater than their faster-growing (and earlier dying) counterparts in more moist environments.

Evidence from Eight Different Types of Studies Showing that Smaller Body Size is Related to Greater Longevity

Aim: To report findings from various sources indicating that smaller sized humans live longer. Study Design: Collected mortality and longevity data from a variety of diverse studies involving animals and humans. Also collected longevity data from many nations and ethnic groups. Evaluated a broad range of biological parameters that may explain why smaller people live longer. Methodology: Over 145 mortality, life expectancy, and longevity studies were evaluated based on over 5000 papers, reports, and books collected over the last 35 years. Thirty studies were selected for this mini review to provide a balanced variety of findings. Results: Evidence was collected on eight different types of studies. For example, studies were found showing smaller body size is related to greater longevity within the same species. Other studies involved longevity in relation to caloric restriction, male-female height differences, and US ethnic group heights. Other data sources indicated that shorter developed populations have longer life expectancies compared to the tallest populations. Longevity studies showed that shorter people lived longer. Worldwide, centenarians were also found to be short and lean based on their military heights or when adult heights were adjusted for shrinkage. A list of 11 biological factors identified why shorter, lighter bodies survive longer. Conclusions: The evidence indicates that shorter, smaller bodies are healthier and longer-lived when healthful nutrition and lifestyles are followed. Therefore, emphasizing Mini-review Article

English

This study was focused on genetic evaluation of longevity in Croatian Simmental cattle using linear and survival models. The main objective was to create a genetic model that is most appropriate to describe the longevity data. Survival analysis, using piecewise Weibull proportional hazards model, used all information on the length of productive life including censored as well as uncensored observations. Linear models considered culled animals only. The relative milk production within herd had a highest impact on cows’ longevity. In comparison of estimated genetic parameters among methods, survival analysis yielded higher heritability value (0.075) than linear sire (0.037) and linear animal model (0.056). When linear models were used, genetic trend of Simmental bulls for longevity was slightly increasing over the years, unlike a decreasing trend in case of survival analysis methodology. Average reliability of bulls’ breeding values was higher in case of survival analysis. The rank correlations between survival analysis and linear models bulls’ breeding values for longevity were ranged between 0.44 and 0.46 implying huge differences in ranking of sires.

Mutation, Condition, and the Maintenance of Extended Lifespan in Drosophila

The evolutionary theory of aging predicts that longevity will decline via drift or age-specific tradeoffs when selection favors early life fitness. Many Drosophila melanogaster populations continually terminated at young adult ages retain surprisingly long postselection lifespans. We compiled three decades of longevity data from the Ives population, demonstrating that postselective longevity was both substantial (30 days) and temporally stable over this period. Recently, alleles with positive pleiotropic effects between adjacent ages, particularly those affecting overall condition, have been integrated into the theory and may explain the extended longevity observed. We experimentally tested this hypothesis by isolating 20 hemiclones from Ives and allowing spontaneous mutations to accumulate (MA) for 35 generations. Fitness and longevity were positively genetically correlated in control females, and both traits declined due to MA. Crucially, MA induced a strong positive genetic correlation between the traits in both sexes, implying that mutations with early-life impacts also reduce late-life survival. Our results suggest that extended postreproductive longevity is actively maintained by selection for early-life fitness via positive pleiotropy and is not a merely a byproduct of exhaustion of genetic variation or weak drift. Thus mutation-selection balance for early fitness may govern variance in longevity in this system: a balance struck remarkably long after selection for continued survival ceases.

Factors affecting lifespan in bird-eating spiders (Arachnida: Mygalomorphae, Theraphosidae) – A multi-species approach

Lifespan is a life-history trait being of utmost importance, as it is frequently closely related to individual fitness. However, interspecific comparisons are relatively rare, being hampered by the high effort to collect longevity data across taxa. We here compiled lifespan data for 85 species of bird-eating spiders (Theraphosidae) held in captivity, based on 2183 individual records from the animal record books of both zoological gardens of Berlin, Germany. Using a data-mining approach we sought for broad patterns of correlations between lifespan and an array of other variables as derived from the literature. We found that the subfamily Eumenophoriinae lived on average longest, followed by the Theraphosinae, Ornithoctinae, Grammostolinae, Selenocosmiinae, Ischnocolinae and finally the Avicularinae. Species inhabiting tropical, more humid and/or low-altitude environments lived longer, suggesting that more predictable environments facilitate the evolution of longer lifespans. Furthermore, large range size, low abundance, sub-terrestrial life-style, and aggressive behavior were all associated with longer lifespans. Evidence for resource allocation trade-offs was revealed as larger spiderling and prosoma size was negatively related to longevity. Our rather rough approach revealed several patterns worth of future investigations, and illustrate the value of zoo records for interspecific comparisons.