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Cited by 15Animal Behavior and ReproductionWildlife Ecology and ConservationInsurance, Mortality, Demography, Risk Management

The DOI matches its Crossref record; 14 of the 14 references it cites were found in a registry or an index; 1 of the 10 sources its claims cite were checked for support.

Sex-specific median life expectancies from ex situ populations for 330 animal species

Open access
Che-Castaldo, Judy P., Byrne, Amy, Perišin, Kaitlyn, Faust, Lisa J.·2019·Scientific Data
DOI 10.1038/sdata.2019.19PMC PMC6484356
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Abstract

We present life expectancy estimates for hundreds of vertebrate species based on carefully vetted studbook data from North American zoos and aquariums. These data include sex-specific median life expectancies as well as sample size and 95% confidence limits for each estimate. Existing longevity data for animals primarily consist of maximum lifespan values, which are single observations rather than statistically derived estimates of longevity. Moreover, all of our estimates are based on the same type of data and calculated using consistent, standardized methods. To derive these estimates, we conducted Kaplan-Meier survival analyses using individual-level demographic data (i.e., records of birth and mortality events) from studbook records for each ex situ population. Our species set represents a range of vertebrate taxa (primarily mammals, birds, amphibians, and reptiles) and diverse life histories. This dataset will have broad utility, not only for informing comparative demographic and life history studies, but also more broadly for any research or conservation application that requires sex- or species-specific life expectancy information.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This paper presents a dataset of sex-specific median life expectancies (MLEs) for 330 animal species or subspecies, derived from vetted North American zoo and aquarium studbooks using Kaplan-Meier survival analysis. It provides MLEs, sample sizes, and 95% confidence limits for ex situ populations, with estimates for 270 female and 258 male populations after excluding insufficient data.

Key findings

  • The dataset includes 330 unique species or subspecies, with female MLE estimates for 270 populations and male MLE estimates for 258 populations.
  • Sample sizes ranged from 41 individuals (female Madagascar buttonquail) to 1,425 individuals (male Caribbean flamingo); mean sample size was 254.1 (±209.4 SD) for female MLEs and 242.1 (±198.7 SD) for male MLEs.
  • Most MLEs came from survival analyses conducted in the past 5 years: 309 of 330 records were from 2014–2018, with the remainder from 2010–2013.
  • The dataset also includes overall MLEs based on all studbook data, plus sex-specific MLEs, sample sizes, and 95% confidence limits; two columns flag whether male or female estimates failed at least one of five data quality tests.

Methods

  • Individual-level demographic data were obtained from validated studbooks for ex situ populations in North American zoos and aquariums, primarily Association of Zoos and Aquariums (AZA) member institutions and collaborating non-member institutions.
  • Age-specific survival probabilities were estimated using non-parametric Kaplan-Meier survival analysis, handling right censoring and left truncation; analysis start age was set at 365 days, and time windows typically began in 1980 or later.
  • MLE was calculated as the age at which survival probability equaled 0.5 via linear interpolation, then divided by 365 to yield years; 95% log-transformed confidence intervals were calculated, and calculations were implemented in PopLink version 2.4.

Limitations

  • The paper states that lifespan likely differs between ex situ and in situ settings, so the dataset may only approximate expected longevity for wild animals; existing large-scale wild lifespan datasets mostly contain maximum longevity values and are not comparable with these MLEs.
  • The paper states that individual studbook databases cannot all be shared, and that MLE estimates start at 365 days, excluding individuals that did not survive to their first birthday; users should interpret MLEs as typical life expectancy after surviving the first year.
  • The paper states that estimates failing any of five data quality tests are marked “Data deficient” and may still be reported, but it recommends excluding those values from formal analysis for the most reliable results; the text also makes evident that sex-specific MLEs were not available for all populations.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/sdata.2019.19

Cites

14 of 14 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

1 of 10 cited sources checked · 0 supported · 0 flagged · accuracy not yet measured

  • Findingown data

    In total, the dataset included entries for 330 unique species or subspecies.

    “In total, our dataset included entries for 330 unique species or subspecies.”
    Quote in the paperSubstantial claim
  • Findingown data

    Some populations had sufficient demographic data to reliably estimate MLE only for the overall population or only for one sex.

    “Some populations had sufficient demographic data to reliably estimate MLE only for the overall population or only for one sex.”
    Quote in the paperNot a substantial claim
  • Findingown data

    The longevity estimates are derived from studbooks for animal populations in North American zoos and aquariums.

    “Specifically, our longevity estimates are derived from studbooks for animal populations in North American zoos and aquariums.”
    Quote in the paperSubstantial claim
  • Study design and conductown data

    The studbook data were vetted by population biologists advising each ex situ population.

    “These data are carefully vetted by population biologists working with each population, and we then used them to estimate Kaplan-Meier survival curves and to calculate MLE for each species (see Methods).”
    • Also stated in: § Technical Validation · plain
      “First, each studbook was vetted by the population biologist who was advising the ex situ population (see Methods).”
    Quote in the paperSubstantial claim
  • Premisecitation

    Studbooks contain individual-level demographic information for all animals in the population.

    “The studbooks contain individual-level demographic information (e.g., birthdates, reproduction events, and death dates when applicable) for all animals in the population11.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] Ballou, J. D. et al. In Wild mammals in captivity: Principles and techniques for zoo management (eds Kleiman D. G., Thompson K. V. & Baer C. K. ) Ch. 19. (University of Chicago Press, 2010).

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one. 15
  • Probably not a substantial claim. 24

  • It may state two separate claims as one.

    Premisecitation

    Existing large-scale datasets on animal lifespans from wild populations mostly consist of maximum longevity values, and therefore are not comparable with the median life expectancy estimates.

    “Unfortunately, existing large-scale datasets on animal lifespans from wild populations7–9 mostly consist of maximum longevity values, and therefore are not comparable with our median life expectancy estimates.”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [7] Carey, J. R. & Judge, D. S. Longevity Records: Life Spans of Mammals, Birds, Amphibians, Reptiles, and Fish. (Odense University Press, 2000).
    • cites [8] de Magalhaes, J. P. & Costa, J. A database of vertebrate longevity records and their relation to other life-history traits. J Evol Biol 22, 1770–1774 (2009). source
    • cites [9] Tacutu, R. et al. Human Ageing Genomic Resources: New and updated databases. Nucleic Acids Res 46, D1083–D1109 (2018). source

      The AnAge section (page unavailable) describes a large animal-longevity database whose entries contain maximum longevity values, including values from wild specimens; mortality parameters are available only for some entries. It does not establish that large-scale datasets from wild populations generally consist mostly of maximum values, nor does it discuss comparison with median life expectancy estimates. (LLM, conf=0.82)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Findingown data

    The mean sample size across species was 254.1 (±209.4 SD) individuals for female MLEs, and 242.1 (±198.7 SD) individuals for male MLEs.

    “The mean sample size across species was 254.1 (±209.4 SD) individuals for female MLEs, and 242.1 (±198.7 SD) individuals for male MLEs.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingreasoning

    The analysis time windows were typically from 1980 or later to the present.

    “The resulting analysis time windows were typically from 1980 or later to the present.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    The dataset includes over 300 vertebrate species, primarily mammals and birds but also reptiles and amphibians.

    “Our dataset includes over 300 vertebrate species, which primarily consist of mammals and birds but also include a number of reptiles and amphibians (see Data Records).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    Excluding estimates based on insufficient studbook data, the dataset contained estimates of female MLE for 270 populations and of male MLE for 258 populations.

    “Excluding the estimates based on insufficient studbook data, our dataset contained estimates of female MLE for 270 populations and of male MLE for 258 populations.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Findingown data

    The smallest analysis that still produced a sex-specific MLE estimate included 41 individuals (female Madagascar buttonquail), whereas the largest included 1425 individuals (male Caribbean flamingo).

    “In terms of sample sizes, the smallest analysis that still produced a sex-specific MLE estimate included 41 individuals (for female Madagascar buttonquail), whereas the largest included 1425 individuals (for male Caribbean flamingo).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingnone given

    The authors are unable to share all of the individual studbook databases from which the MLE estimates are derived.

    “Unfortunately, we are unable to share all of the individual studbook databases from which our MLE estimates are derived.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Findingown data

    The studbook data used to calculate MLEs represented thousands of animals in AZA member institutions and other collaborating institutions, the majority located in the United States.

    “The studbook data used to calculate MLEs represented thousands of animals in AZA member institutions and other collaborating institutions, the majority of which are located in the United States.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingnone given

    The full MLE dataset has been deposited in figshare.

    “The full MLE dataset has been deposited in figshare (Data Citation 1).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingreasoning

    Values marked as Data deficient were included in the dataset because it may still be informative to know that life expectancy was attempted to be evaluated for those species.

    “We included these values in our dataset as it may still be informative to know that we have attempted to evaluate life expectancy for those species.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Findingown data

    Most of the MLEs came from survival analyses conducted in the past 5 years (309 of 330 records from 2014-2018), and the remaining were analyzed from 2010-2013.

    “Most of the MLEs came from survival analyses that were conducted in the past 5 years (309 of 330 records were from 2014–2018), and the remaining were analyzed from 2010–2013.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    The paper presents life expectancy estimates for hundreds of vertebrate species based on vetted studbook data from North American zoos and aquariums.

    “We present life expectancy estimates for hundreds of vertebrate species based on carefully vetted studbook data from North American zoos and aquariums.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingown data

    Two additional columns indicated whether the male or female MLE estimates were based on datasets that failed at least one of the five data quality tests.

    “Two additional columns in the dataset indicated whether the male or female MLE estimates were based on datasets that failed at least one of the five data quality tests (Data Deficient = “yes”; see Technical Validation).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Findingown data

    The dataset table included species' common name, scientific name, taxonomic group, sample size, MLE estimates, and lower and upper 95% confidence limits.

    “The table included the species’ common name, scientific name, taxonomic group, sample size, MLE estimates (in years), and the lower and upper 95% confidence limits (in years).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingnone given

    Sex-specific MLEs were estimated based on only the male or female data.

    “We also estimated sex-specific MLEs based on only the male or female data.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingown data

    The last four variables were separated into sex-specific columns: overall MLE estimates, male MLE estimates, and female MLE estimates.

    “The last four variables were separated into sex-specific columns: one set for the overall MLE estimates (those calculated from all studbook data including unknown-sex individuals), one set for male MLE estimates (those calculated from male data only), and one set for female MLE estimates (those calculated from female data only).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    The dataset includes sex-specific median life expectancies, sample size, and 95% confidence limits for each estimate.

    “These data include sex-specific median life expectancies as well as sample size and 95% confidence limits for each estimate.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingnone given

    For each population, an overall MLE estimate was calculated based on the entire studbook dataset, including males, females, and any individuals of unknown sex.

    “For each population, we calculated an overall MLE estimate that is based on the entire studbook dataset, including males, females, and any individuals of unknown sex.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    The MLE estimates are derived using the same data sources and consistent methodology for all species, providing reliable quantitative data on the relative longevity among a diverse set of species.

    “The most powerful use of our dataset will lie in comparative analyses, because our MLE estimates are derived using the same data sources and consistent methodology for all species, providing reliable quantitative data on the relative longevity among a diverse set of species.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductnone given

    Attempts are made to resolve records for any individuals with unknown birth or death dates.

    “Attempts are made to resolve records for any individuals with unknown birth or death dates.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. It may state two separate claims as one.

    Study design and conductreasoning

    If the studbook dataset failed any of the five data quality tests, MLE cannot be reliably estimated and the estimate is marked as being "Data deficient," although a value may still be reported.

    “If the studbook dataset failed any of these tests, MLE cannot be reliably estimated and the estimate is marked as being “Data deficient,” although a value may still be reported.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Study design and conductnone given

    Individuals in the studbook that did not survive to their first birthday were excluded from the survival analyses.

    “Individuals in the studbook that did not survive to their first birthday were excluded from the survival analyses.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Study design and conductown data

    The dataset's estimates for all species are derived from the same type of data and from the same sources, and calculated using consistent, standardized methods.

    “Moreover, all of our estimates are based on the same type of data and calculated using consistent, standardized methods.”
    • Also stated in: § Background & Summary · plain
      “Our dataset also differs from existing longevity data because estimates for all species are derived from the same type of data and from the same sources, and calculated using consistent, standardized methods.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Premisereasoning

    Maximum lifespans are usually single observations and can represent outliers rather than biological tendencies.

    “Maximum lifespans are usually single observations, and therefore can represent outliers rather than biological tendencies.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Study design and conductnone given

    A trained population biologist validates each studbook through automated error checking and discussions with program leaders to ensure all records are accurate and common errors are corrected.

    “As part of this process, the biologist validates each studbook through automated error checking and discussions with program leaders to ensure all records are accurate and common errors are corrected.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Study design and conductnone given

    Studbook records with high uncertainty were excluded from the survival analysis.

    “Second, studbook records with high uncertainty were excluded from the survival analysis.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Interpretationnone given

    Because lifespan likely differs between ex situ and in situ settings, the dataset may only provide approximations of the expected longevity for wild animals.

    “Because lifespan likely differs between ex situ and in situ settings, our dataset may only provide approximations of the expected longevity for wild animals.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Lifespan likely differs between ex situ and in situ settings.

  • Probably not a substantial claim.

    Study design and conductnone given

    Individuals with unknown birthdates, unknown dates of other important events, and/or events at unknown or unrecognized institutions were not included in the calculations.

    “Specifically, individuals with unknown birthdates, unknown dates of other important events (e.g., transfers between institutions, death), and/or events at unknown or unrecognized institutions were not included in the calculations.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Study design and conductreasoning

    The starting age for the survival analysis was set at 365 days.

    “By definition, survivorship is 1.0 at the starting age for the analysis, which we set at age 365 days.”
    • Also stated in: § Usage Notes · plain
      “For accurate interpretation of our dataset, we reiterate that the starting age for our survival analysis was set at 365 days for all species.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Study design and conductown data

    The PopLink program applied five data quality tests to determine whether each studbook contained sufficient data to provide reliable estimates of MLE.

    “Third, the PopLink program applied five data quality tests to determine whether each studbook contained sufficient data to provide reliable estimates of MLE:”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Interpretationreasoning

    Users should interpret the MLE estimates as the typical life expectancy after an animal has survived its first year.

    “Users should interpret our MLE estimates as the typical life expectancy after an animal has survived its first year.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper may give no reason why it holds. It may state two separate claims as one.

    Interpretationnone given

    Mortality in the first year of life can be highly dependent both on life history and on the specific management or animal care strategies at the time and may not be generalizable across settings.

    “This was because mortality in the first year of life can be highly dependent both on life history and on the specific management or animal care strategies at the time and may not be generalizable across settings.”
    Quote in the paperNot a substantial claim
32 of 32

  • The paper relies on this without support.

    Typical studbook errors affecting longevity estimates include entries for life events after a death event, missing death events leading to very old individuals, and duplicated entries for an individual.

    “Typical studbook errors affecting longevity estimates include having entries for life events after a death event, missing death events leading to very old individuals, and duplicated entries for an individual.”

  • The paper relies on this without support.

    Lifespan likely differs between ex situ and in situ settings.

    “Because lifespan likely differs between ex situ and in situ settings, our dataset may only provide approximations of the expected longevity for wild animals.”
2 of 2

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Klein and Moeschberger cited with the wrong reference number

    Minor

    The text identifies Klein and Moeschberger as reference 12, but the reference list assigns their book number 13. Reference 12 is by Ballou et al.

1 of 1

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Metadata

Authors
Che-Castaldo, J. P., Byrne, A., Perišin, K., & Faust, L. J.
Affiliations
Lincoln Park Zoo (US)
ORCID
Che-Castaldo, Judy P.
Venue
Scientific Data
Publisher
Springer Science and Business Media LLC
Published
2019-02-19
Volume
6
Issue
1
Pages
190019-190019
ISSN
2052-4463 (ISSN-L)
DOI
10.1038/sdata.2019.19
PMC
PMC6484356
OpenAlex
W2917264668
Semantic Scholar
7e71e029abb5d5ed72985f2b8226728942fdbfbb
Cited by
15
References
14
Citations by year
2026: 4 · 2025: 1 · 2023: 2 · 2022: 2 · 2021: 1 · 2020: 3 · 2019: 2
Type
data paper
Language
en
Open access
Licence
Locations
  • Scientific Data (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Funders
  • Institute of Museum and Library Services
  • Arcus Foundation
Topics
  • Life Sciences › Agricultural and Biological Sciences › Ecology, Evolution, Behavior and Systematics › Animal Behavior and Reproduction
  • Physical Sciences › Environmental Science › Ecology › Wildlife Ecology and Conservation
  • Social Sciences › Demography › Insurance, Mortality, Demography, Risk Management
Keywords
life expectancy, longevity, ex situ populations, captive animals, vertebrates, mammals, birds, amphibians, reptiles, survival analysis, maximum lifespan
MeSH terms
Amphibians, Animals, Animals, Zoo, Birds, Data Interpretation, Statistical, Female, Life Expectancy, Male, Mammals, Reptiles, Sex Factors, Species Specificity

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