RT Journal Article
T1 Classic hypotheses of area, time, and climatic stability fall short in explaining high tropical species richness
A1 Galván, Sofía
A1 Varela, Sara
A1 Gamboa Jurado-Centurión, Sara
AB AimTropical biodiversity overshadows the number of species inhabiting other regions. Age, area, and stability constitute three classical ideas used to explain the higher richness in these warm and humid zones. In this study, we measured the global dynamics of tropical, arid, temperate, cold, and polar climate zones over the last 5 million years (Ma). We aimed to evaluate whether the age, area, and stability of these climate zones contribute to explain the observed differences in species richness.LocationGlobal land.TaxaAmphibians, birds, and mammals.MethodsWe classified the paleoclimatic layers generated by the PALEO-PGEM climatic emulator—temperature and precipitation for the last 5 Ma at 1000-year intervals—into the main Köppen-Geiger climate zones: tropical, arid, temperate, cold, and polar. We then calculated three variables: age, area, and stability. Age represents the duration that each map cell has remained within its current climate zone since its last change (map cell-based measure). Area quantifies the total extent of each climate zone over time by summing all map cells corresponding to that climate zone (climate zone-based measure). Stability indicates the number of times a given map cell changed between climate zones over time (map cell-based measure). We implemented regression and correlation tests, Structural Equation Models, and decision trees to measure the relationship between these estimates and current global patterns of amphibian, bird, and mammal richness.ResultsOur results indicate that age, area, and stability do not account for the observed differences in species richness among the 5 climate zones.Main ConclusionsNone of these classical hypotheses alone can explain the high vertebrate tropical richness observed. Further investigation, incorporating additional taxa (e.g. invertebrates or plants), or integrating new perspectives (such as the influence of local variations in diversification processes) will provide a more comprehensive understanding of the factors shaping large-scale biodiversity patterns.
PB Wiley
SN 0305-0270
YR 2025
FD 2025-03-26
LK https://hdl.handle.net/20.500.14352/120650
UL https://hdl.handle.net/20.500.14352/120650
LA eng
NO Galván, S., Varela, S., & Gamboa, S. (2025). Classic hypotheses of area, time, and climatic stability fall short in explaining high tropical species richness. Journal of Biogeography, 52(6), e15126. https://doi.org/10.1111/jbi.15126
NO European Research Council
NO MCIN/AEI/10.13039/501100011033/
NO Universidade de Vigo
NO Ministerio de Universidades
NO Next Generation European Union
NO Universidad Complutense de Madrid
NO Xunta de Galici
DS Docta Complutense
RD 19 mar 2026