Variability in life-history and ecological traits is a buffer against extinction in mammals

• Published in: Ecology letters 2013-02, Vol.16 (2), p.242-251
• Main Authors: González-Suárez, Manuela, Revilla, Eloy
• Format: Article
• Language: English
• Subjects: Age Factors; Animal and plant ecology; Animal populations; Animal, plant and microbial ecology; Animals; Biological and medical sciences; Body Weight; Comparative studies; Conservation biology; Endangered Species; Extinction; Extinction, Biological; Female; Fundamental and applied biological sciences. Psychology; General aspects; Human influences; intraspecific variation; Life cycles; Litter Size; Male; Mammalia; Mammals; Mammals - physiology; PanTHERIA; Population Density; Red List; taxonomically informed regression; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; vulnerability
• ISSN: 1461-023X; 1461-0248
• DOI: 10.1111/ele.12035

Anthropogenic degradation of the world's ecosystems is leading to a widespread and accelerating loss of biodiversity. However, not all species respond equally to existing threats, raising the question: what makes a species more vulnerable to extinction? We propose that higher intraspecific variability may reduce the risk of extinction, as different individuals and populations within a species may respond differently to occurring threats. Supporting this prediction, our results show that mammalian species with more variable adult body masses, litter sizes, sexual maturity ages and population densities are less vulnerable to extinction. Our findings reveal the role of local variation among populations, particularly of large mammals, as a buffering mechanism against extinction, and emphasise the importance of considering trait variation in comparative analyses and conservation management.