Humidity levels drive reproductive modes and phylogenetic diversity of amphibians in the Brazilian Atlantic Forest

Author(s)

da Silva, Fernando Rodrigues ^[1] ; Almeida-Neto, Mario ^[2] ; Mendonca do Prado, Vitor Hugo ^[3] ; Baptista Haddad, Celio Fernando ^[3] ; Rossa-Feres, Denise de Cerqueira ^[4]

Affiliation

^[1] Univ Fed Sao Carlos, UFSCar, Dept Ciencias Ambientais, BR-18052780 Sorocaba, SP - Brazil

^[2] Univ Fed Goias UFG, Dept Ecol, Inst Ciencias Biol, BR-74001970 Goiania, Go - Brazil

^[3] UNESP, Dept Zool, Inst Biociencias, BR-13506900 Rio Claro, SP - Brazil

^[4] Univ Estadual Paulista, Dept Zool & Bot, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Journal of Biogeography; v. 39, n. 9, p. 1720-1732, SEP 2012.
• Web of Science Citations: 31

Abstract

Aim The diversity of reproductive modes among amphibians constitutes a striking example of how differences in the biology of species provide important explanations for species distribution patterns on a broad scale. We hypothesize that sites with a higher humidity level will support more modes of reproduction than drier sites and will consequently exhibit a higher phylogenetic diversity. Furthermore, if there is a gradient in the tolerance of reproductive modes to desiccation, there will be a nested pattern in the composition of reproductive modes among sites. Location Twenty-seven forest sites in the Brazilian Atlantic Forest. Methods Through a path analysis approach, we evaluated the direct and indirect effects of the humidity level on the number of reproductive modes, as well as the relative importance of both variables on amphibian phylogenetic diversity. A nestedness analysis was used to quantify the extent to which the compositions of both species and reproductive modes in drier sites correspond to subsets of those in sites with higher annual precipitation. Results We found that the reproductive modes present in drier sites are non-random subsets of those present in sites with higher humidity levels. Because reproductive modes are phylogenetically conserved among amphibians, sites with a greater number of reproductive modes supported greater phylogenetic diversity. Sites with high precipitation throughout the year provided suitable environmental conditions for a larger number of reproductive modes, whereas sites with low precipitation and typical seasonal climates supported only those reproductive modes specialized to resist desiccation. Main conclusions Our results show that humidity-related variables are key environmental factors related to both the richness of reproductive modes and phylogenetic diversity. Our results support the hypothesis that the higher phylogenetic diversity found in moister sites reflects differences in the tolerance to desiccation among different reproductive modes. Given that reproductive modes are associated with susceptibility to desiccation, their incorporation into explanatory models may trigger a significant advance in the understanding of the mechanisms regulating the species richness and composition of amphibian communities. (AU)

• FAPESP's process: 08/50928-1 - Speciation of frogs in high-altitude environments
• Grantee: Célio Fernando Baptista Haddad
• Support type: Research Projects - Thematic Grants
• FAPESP's process: 11/20677-0 - Species diversity and coexistence: what is the role of these components in the morphological variation within South American hilid frogs?
• Grantee: Vitor Hugo Mendonça do Prado
• Support type: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 04/04820-3 - Fauna and flora from forest fragments in the northwest region of São Paulo State: the basis to biodiversity conservational studies
• Grantee: Orlando Necchi Junior
• Support type: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 06/51534-1 - Use of forest remnants by anurans in the North-east region of the State of São Paulo
• Grantee: Vitor Hugo Mendonça do Prado
• Support type: Scholarships in Brazil - Doctorate