Marine latitudinal diversity gradients: Tests of causal hypotheses
AUTOR(ES)
Roy, Kaustuv
FONTE
The National Academy of Sciences
RESUMO
Latitudinal diversity gradients are first-order expressions of diversity patterns both on land and in the oceans, although the current hypotheses that seek to explain them are based chiefly on terrestrial data. We have assembled a database of the geographic ranges of 3,916 species of marine prosobranch gastropods living on the shelves of the western Atlantic and eastern Pacific Oceans, from the tropics to the Arctic Ocean. Western Atlantic and eastern Pacific diversities are similar, and the diversity gradients are strikingly similar despite many important physical and historical differences between the oceans. This shared diversity pattern cannot be explained by: (i) latitudinal differences in species range-length (Rapoport’s rule); (ii) species-area effects; or (iii) recent geologic histories. One parameter that does correlate significantly with diversity in both oceans is solar energy input, as represented by average sea surface temperature. If this correlation is causal, sea surface temperature is probably linked to diversity through some aspect of productivity. In this case, diversity is an evolutionary outcome of trophodynamic processes inherent in ecosystems, and not just a byproduct of physical geographies.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=19899Documentos Relacionados
- Surface tension gradients: feasible model for gliding motility of Myxococcus xanthus.
- Bacteria are not too small for spatial sensing of chemical gradients: An experimental evidence
- A model for reading morphogenetic gradients: autocatalysis and competition at the gene level.
- Latitudinal gradients of species richness in the deep-sea benthos of the North Atlantic
- Preference behavior of silver catfish, Rhamdia quelen, juveniles in waters with pH gradients: laboratory experiments