Animals 2011, 1(2), 205-241; doi:10.3390/ani1020205
Article

Aquatic Biodiversity in the Amazon: Habitat Specialization and Geographic Isolation Promote Species Richness

1 Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504, USA 2 The Nature Conservancy and Museum of Comparative Zoology, Harvard University, MA 02138, USA 3 Museo de Historia Natural, Universidad Nacional de San Marcos, Lima, Peru 4 Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
* Author to whom correspondence should be addressed.
Received: 22 February 2011; in revised form: 21 April 2011 / Accepted: 22 April 2011 / Published: 29 April 2011
(This article belongs to the Special Issue Evolutionary Aspects of Taxonomic Diversity Patterns)
PDF Full-text Download PDF Full-Text [1524 KB, Updated Version, uploaded 3 May 2011 12:15 CEST]
The original version is still available [1526 KB, uploaded 2 May 2011 11:29 CEST]
Simple Summary: The immense rainforest ecosystems of tropical America represent some of the greatest concentrations of biodiversity on the planet. Prominent among these are evolutionary radiations of freshwater fishes, including electric eels, piranhas, stingrays, and a myriad of small-bodied and colorful tetras, cichlids, and armored catfishes. In all, the many thousands of these forms account for nearly 10% of all the vertebrate species on Earth. This article explores the complimentary roles that ecological and geographic filters play in limiting dispersal in aquatic species, and how these factors contribute to the accumulation of species richness over broad geographic and evolutionary time scales.
Abstract: The Neotropical freshwater ichthyofauna has among the highest species richness and density of any vertebrate fauna on Earth, with more than 5,600 species compressed into less than 12% of the world’s land surface area, and less than 0.002% of the world’s total liquid water supply. How have so many species come to co-exist in such a small amount of total habitat space? Here we report results of an aquatic faunal survey of the Fitzcarrald region in southeastern Peru, an area of low-elevation upland (200–500 m above sea level) rainforest in the Western Amazon, that straddles the headwaters of four large Amazonian tributaries; the Juruá (Yurúa), Ucayali, Purús, and Madre de Dios rivers. All measures of fish species diversity in this region are high; there is high alpha diversity with many species coexisting in the same locality, high beta diversity with high turnover between habitats, and high gamma diversity with high turnover between adjacent tributary basins. Current data show little species endemism, and no known examples of sympatric sister species, within the Fitzcarrald region, suggesting a lack of localized or recent adaptive divergences. These results support the hypothesis that the fish species of the Fitzcarrald region are relatively ancient, predating the Late Miocene-Pliocene (c. 4 Ma) uplift that isolated its several headwater basins. The results also suggest that habitat specialization (phylogenetic niche conservatism) and geographic isolation (dispersal limitation) have contributed to the maintenance of high species richness in this region of the Amazon Basin.
Keywords: freshwater fishes; geodispersal; species diversity; species richness; stream capture; tropical rainforest; vicariance

Article Statistics

Load and display the download statistics.

Citations to this Article

Cite This Article

MDPI and ACS Style

Albert, J.S.; Carvalho, T.P.; Petry, P.; Holder, M.A.; Maxime, E.L.; Espino, J.; Corahua, I.; Quispe, R.; Rengifo, B.; Ortega, H.; Reis, R.E. Aquatic Biodiversity in the Amazon: Habitat Specialization and Geographic Isolation Promote Species Richness. Animals 2011, 1, 205-241.

AMA Style

Albert JS, Carvalho TP, Petry P, Holder MA, Maxime EL, Espino J, Corahua I, Quispe R, Rengifo B, Ortega H, Reis RE. Aquatic Biodiversity in the Amazon: Habitat Specialization and Geographic Isolation Promote Species Richness. Animals. 2011; 1(2):205-241.

Chicago/Turabian Style

Albert, James S.; Carvalho, Tiago P.; Petry, Paulo; Holder, Meghan A.; Maxime, Emmanuel L.; Espino, Jessica; Corahua, Isabel; Quispe, Roberto; Rengifo, Blanca; Ortega, Hernan; Reis, Roberto E. 2011. "Aquatic Biodiversity in the Amazon: Habitat Specialization and Geographic Isolation Promote Species Richness." Animals 1, no. 2: 205-241.

Animals EISSN 2076-2615 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert