Geographical gradients in seed mass in relation to climate

Blackwell Publishing Ltd
Publication Type:
Journal Article
Journal Of Biogeography, 2004, 31 (3), pp. 379 - 388
Issue Date:
Full metadata record
Files in This Item:
Filename Description Size
Thumbnail2004000116.pdf136.34 kB
Adobe PDF
To determine whether latitudinal and longitudinal gradients in seed mass are related to variation in climatic features including temperature, solar radiation and rainfall. Location Australia. Methods Seed mass was estimated from over 1600 provenances covering the latitudinal and longitudinal extents of 34 perennial Glycine taxa in Australia. Climatic data were obtained from ANUCLIM 5.1 for collection locations based on long-term meteorological records across Australia. These climatic data were subject to principal components analysis to extract three components as climatic indices. Generalized linear models were used in three separate sets of analyses to evaluate whether seed masslatitude and seed masslongitude relationships persisted after taking climatic variation into account. First, relationships were examined across species in analyses that did not explicitly consider phylogenetic relationships. Secondly, phylogenetic regressions were performed to examine patterns of correlated evolutionary change throughout the Glycine phylogeny. Within-species analysis was also performed to examine consistency across different taxonomic levels. Results Geographical variation in seed mass among species was related primarily to temperature and solar radiation, while rainfall was much less influential upon seed mass. Partialing out the influence of temperature and solar radiation in models resulted in the disappearance of significant seed masslatitude and seed masslongitude relationships. Patterns within species were generally consistent with patterns among species. However, in several species, factors additional to these climatic variables may contribute to the origin and maintenance of geographical gradients in seed mass, as significant seed masslatitude and seed masslongitude relationships remained after controlling for the influence of climatic variables.
Please use this identifier to cite or link to this item: