A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Asian elephants exhibit post-reproductive lifespans
Tekijät: Chapman SN, Jackson J, Htut W, Lummaa V, Lahdenperä M
Kustantaja: BMC
Julkaisuvuosi: 2019
Journal: BMC Evolutionary Biology
Tietokannassa oleva lehden nimi: BMC EVOLUTIONARY BIOLOGY
Lehden akronyymi: BMC EVOL BIOL
Artikkelin numero: ARTN 193
Vuosikerta: 19
Numero: 1
Sivujen määrä: 11
ISSN: 1471-2148
eISSN: 1471-2148
DOI: https://doi.org/10.1186/s12862-019-1513-1
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/43467790
Tiivistelmä
Background The existence of extended post-reproductive lifespan is an evolutionary puzzle, and its taxonomic prevalence is debated. One way of measuring post-reproductive life is with post-reproductive representation, the proportion of adult years lived by females after cessation of reproduction. Analyses of post-reproductive representation in mammals have claimed that only humans and some toothed whale species exhibit extended post-reproductive life, but there are suggestions of a post-reproductive stage for false killer whales and Asian elephants. Here, we investigate the presence of post-reproductive lifespan in Asian elephants using an extended demographic dataset collected from semi-captive timber elephants in Myanmar. Furthermore, we investigate the sensitivity of post-reproductive representation values to availability of long-term data over 50 years. Results We find support for the presence of an extended post-reproductive stage in Asian elephants, and that post-reproductive representation and its underlying demographic rates depend on the length of study period in a long-lived animal. Conclusions The extended post-reproductive lifespan is unlikely due to physiological reproductive cessation, and may instead be driven by mating preferences or condition-dependent fertility. Our results also show that it is crucial to revisit such population measures in long-lived species as more data is collected, and if the typical lifespan of the species exceeds the initial study period.
Background The existence of extended post-reproductive lifespan is an evolutionary puzzle, and its taxonomic prevalence is debated. One way of measuring post-reproductive life is with post-reproductive representation, the proportion of adult years lived by females after cessation of reproduction. Analyses of post-reproductive representation in mammals have claimed that only humans and some toothed whale species exhibit extended post-reproductive life, but there are suggestions of a post-reproductive stage for false killer whales and Asian elephants. Here, we investigate the presence of post-reproductive lifespan in Asian elephants using an extended demographic dataset collected from semi-captive timber elephants in Myanmar. Furthermore, we investigate the sensitivity of post-reproductive representation values to availability of long-term data over 50 years. Results We find support for the presence of an extended post-reproductive stage in Asian elephants, and that post-reproductive representation and its underlying demographic rates depend on the length of study period in a long-lived animal. Conclusions The extended post-reproductive lifespan is unlikely due to physiological reproductive cessation, and may instead be driven by mating preferences or condition-dependent fertility. Our results also show that it is crucial to revisit such population measures in long-lived species as more data is collected, and if the typical lifespan of the species exceeds the initial study period.
Ladattava julkaisu This is an electronic reprint of the original article. |