Life history predicts risk of species decline in a stochastic world

Department of Ecology and Evolutionary Biology, Rice University, Houston, TX 77005, USA.
Proceedings of the Royal Society B: Biological Sciences (Impact Factor: 5.05). 03/2012; 279(1738):2691-7. DOI: 10.1098/rspb.2012.0185
Source: PubMed


Understanding what traits determine the extinction risk of species has been a long-standing challenge. Natural populations increasingly experience reductions in habitat and population size concurrent with increasing novel environmental variation owing to anthropogenic disturbance and climate change. Recent studies show that a species risk of decline towards extinction is often non-random across species with different life histories. We propose that species with life histories in which all stage-specific vital rates are more evenly important to population growth rate may be less likely to decline towards extinction under these pressures. To test our prediction, we modelled declines in population growth rates under simulated stochastic disturbance to the vital rates of 105 species taken from the literature. Populations with more equally important vital rates, determined using elasticity analysis, declined more slowly across a gradient of increasing simulated environmental variation. Furthermore, higher evenness of elasticity was significantly correlated with a reduced chance of listing as Threatened on the International Union for Conservation of Nature Red List. The relative importance of life-history traits of diverse species can help us infer how natural assemblages will be affected by novel anthropogenic and climatic disturbances.

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Available from: Amy E. Dunham, Dec 20, 2013
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    • "In a highly anthropogenic world, with alarming climate change predictions and limited funding for conservation , it is vital to develop more accurate and case-specific frameworks to prioritize conservation actions and aid mitigation. Differences in species extinction risk have been partially attributed to variation in biological traits (Pearson et al., 2014;Van Allen et al., 2012). Indeed, habitat preferences, ecological traits and demographic characteristics have been successfully used to predict species' extinction risk (e.g.Cardillo et al., 2005;Davies et al., 2004;Lee and Jetz, 2011;Pearson et al., 2014). "
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    • "The link between ELHT of species and their responses to disturbance has resulted in an increasing number of authors investigating the use of biological attributes, alone or combined, for evaluating species vulnerability to environmental changes (Davies et al., 2000; Cardillo et al., 2008; Dalgleish et al., 2010; Angert et al., 2011). This has confirmed the value of multiple combinations of biological attributes to predict species occurrence and relative abundance within communities or habitats (Newbold et al., 2013), or their endangered status (Murray et al., 2011; Cardillo et al., 2008; Anderson et al., 2011; Allen et al., 2012). However, studies investigating the links between combinations of biological attributes and inter-specific variations in temporal demographic response to perturbations are still sparse (Olden et al., 2006; Pocock, 2010). "
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