INTEGRATING PHYLOGENETICS AND NICHE MODELING TO ELUCIDATE THE DIVERSIFICATION PROCESSES IN SOUTH AMERICAN GRASSHOPPERS (ACRIDIDAE: MELANOPLINAE)

SCATTOLINI, M. CELESTE; CONFALONIERI, A. VIVIANA; CIGLIANO, MARÍA MARTA

Ilhéus

Congreso; 12th International Congress of Orthopterology; 2016

INTEGRATING phylogenetic hypotheses with geographic and ecological data has revealed new insights on the factors that influence the evolution and distribution of species. The spatial and temporal distribution of a species is shaped by its fundamental niche, which determines the potential distribution. Incorporating environmental and ecological data in a phylogenetic context allows the identification of phylogenetic signals in niche dimensions. These analyses provide a measure of niche similarity between related species, which can be used to build hypotheses on niche and range evolution and help to elucidate radiation mechanisms. Most attempts to infer diversification processes have compared geographic ranges in relation to phylogenies without considering the environmental space occupied. Inclusion of an environmental dimension in these analyses can allow us to assess whether ecologically mediated divergent selection is associated with speciation. The grasshopper genus Scotussa together with the remaining taxa of the Scotussae group are mostly distributed in Brazil, Paraguay, Uruguay and Argentina occurring in the Chacoan and Parana dominions of South America.Contrary to the general pattern observed within the tribe Dichroplini, Scotussa species are highly variable in the structure of their ovipositor valves. Besides, it has been shown an association between the structural changes that occurred in the ovipositor of species of Scotussa with their oviposition habits. However, it was never tested if this association was related to the diversification processes occurred within the genus. In this study, we reanalyze the phylogenetic relationships among species of Scotussa adding new morphological and molecular data and use environmental variables to (1) predict the potential distribution of each species (2) quantify geographical and environmental niche overlap among species, and (3) to analyze niche evolution combining phylogenetic information and georeferenced occurrence records in order to investigate the diversification of the species.