Data from: Patterns and drivers of intraspecific variation in avian life history along elevational gradients: a meta-analysis

Using three analytical methods, we found that fecundity declined at higher elevations due to smaller clutches and fewer reproductive attempts per year. By contrast, elevational differences in traits associated with parental investment or survival varied among studies. High-elevation populations had shorter and later breeding seasons, but longer developmental periods implying that temporal constraints contribute to reduced fecundity.

Analyses of clutch size data, the trait for which we had the largest number of population comparisons, indicated no evidence that phylogenetic history constrained species-level plasticity in trait variation associated with elevational gradients. The magnitude of elevational shifts in life-history traits were largely unrelated to geographic (altitude, latitude), intrinsic (body mass, migratory status), or habitat covariates.

Meta-population structure, methodological issues associated with estimating survival, or processes shaping range boundaries could potentially explain the nature of elevational shifts in life-history traits evident in this data set. We identify a new risk factor for montane populations in changing climates: low fecundity will result in lower reproductive potential to recover from perturbations, especially as fewer than half of the species experienced higher survival at higher elevations.

Usage notes

Avian Life History Trait Dataset Core dataset upon which the study was based. Details of contents described in the ReadMe file. ALHTDataset.csv ALHTTreesFile File containing 500 phylogenetic trees for the taxa included in tests of phylogenetic signal in responses of clutch size to elevational differences as described in the README file associated with the main data file.