Habitat split, defined as human-induced disconnection between habitats used by different life history stages of a species, is a strong factor negatively affecting the richness of Brazilian Atlantic Forest amphibians. Here, the disconnection between streams and forest fragments is shown to reduce the proportion of species with aquatic larvae in local communities.3205878 Becker, C.G., Fonseca, C.R., Haddad, C.F.B., Batista, R.F., Prado, P.I., (2007) Science, 318, p. 1775Cannatella, D.C., (2008) Science, 320, p. 874. , www.sciencemag.org/cgi/content/full/320/5878/874cComulada, W.S., Weiss, R.E., (2007) Biometrics, 63, p. 610Dobson, A.J., (2002) An Introduction to Generalized Linear Models, , Chapman & Hall/CRC, New York, ed. 2McCullagh, P., Nelder, J.A., (1989) Generalized Linear Models, , Chapman & Hall/CRC, New York, ed. 2www.R-project.org, R Development Core Team, R Version 2.6.1 R Foundation for Statistical Computing, Vienna, 2007www.cran.r-project.org, B. Bolker, bbmle: Tools for general maximum likelihood estimation R package, Version 0.8.2, 2008SYSTAT, SYSTAT for Windows, version 10.2.01 Richmond, CA, 2002SAS Institute Inc, SAS/STAT, version 8.3 Cary, NC, 2001Zou, G., (2004) Am. J. Epidemiol, 159, p. 702Spiegelman, D., Hertzmark, E., (2005) Am. J. Epidemiol, 162, p. 199An alternative approach to test the influence of habitat split, habitat loss, and habitat fragmentation on the proportion of amphibian species with aquatic larvae is the use of a Poisson multiple regression model with a robust error variance implemented in the module Proc Genmod in SAS (9, This method, which assumes a log link and a binomial distribution, has proven to perform better than logistic regression when frequencies are considerably high and sample sizes are small (10, 11, In our data set, the proportions of species aquatic larvae in communities are high (minimum, 0.47, maximum, 0.80, and the number of independent data points is limited (N, 12 sites, The response variable is defined by the number of species with aquatic larvae (number of events) and by the total species richness number of trials, The full model contained the three landscape variables and their higher-order interactions as explanatory variablesthe minimal adequate model was estabBlank, S., Seiter, C., Bruce, P., (1999) Resampling Stats in Excel, , Arlington, VAMelnick, R., Johnson, B., Hill, K., (2001) Ecology and Design: Frameworks for Learning, , Island Press, Washington, DCWe thank K. R. Zamudio and G. Ganade for critically reviewing previous versions of the manuscript and J. Fox and E. M. Wendland for assistance in the statistical analyses. C.G.B. received a scholarship from the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP: 04/13132-3). C.R.F. and C.F.B.H. received fellowships from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq: 305428/2005-5, 302512/2005-5). This project was supported by the Programa de Pesquisas em Caracterização, Conservação e Uso Sustentável da Biodiversidade do Estado de São Paulo da Fundação de Amparo à Pesquisa do Estado de São Paulo (BIOTA/FAPESP 01/13341-3 and 02/08558-6) and Universidade do Vale do Rio dos Sinos