Posted by on 2014/07/18

The big disparities in species richness among evolutionary lineages have been fascinating and challenging scientists since Darwin’s time. Although geographical factors have been traditionally thought to promote speciation, the importance of ecological interactions as one of the drivers of diversification has been underscored. For example, is it possible to wonder that food quality might influence patterns of diversification in coral reefs? A new study conducted in Brazil and Australia shows that this is an important aspect to account for when looking at the evolution of coral reef fishes. The evolutionary relationships of four major reef fish groups were used to test if differences in the number of species among lineages match predictions of “density-dependent” diversification. According to this concept, as ecological niche-space (in this case food resources) become increasingly occupied, fewer opportunities for speciation occur. To test this idea, the authors assessed whether niche shifts toward usage of relatively low energy/protein food resources, such as algae, detritus, sponges and corals were accompanied by rapid diversification in fish lineages. Interestingly, the predictions were met in most groups, suggesting that ecological opportunity may play an important role in the evolution of diverse groups such as reef fishes. The full study ‘Diet and Diversification in the Evolution of Coral Reef Fishes’ has been published by

PLoS ONE.

Posted in: Publications, Research