Toward the Knowledge of the Evolutionary Biology of Phalangopsid Crickets (Orthoptera: Grylloidea: Phalangopsidae): Data, Questions and Evolutionary Scenarios

-The Phalangopsidae are one of the most important cricket families of the world, both in terms of taxa number and ecological diversity. Although they can be directly observed in the field and easily raised in laboratories, few data are yet available on their biology. In this paper, the present state of the systematics of Phalangopsidae is briefly indicated, and available data are given on their habitats and acoustic and mating behavior (mainly on the basis of my observations in the field). The methodological framework recently developed in comparative biology is used to analyze the evolution of phalangopsid biological characteristics in reference to phylogeny (ancestral state and evolutionary changes). Evolutionary scenarios based on my phylogenetic studies are proposed. In particular, the evolution of the habitats and mating behavior of Central American Amphiacustae is analyzed. Evolutionary changes of habitat could be the consequence of the exploitation of a new resource, or of geographical expansion. Moreover, the evolutionary potentialities of members of a clade appear constrained by the characteristics of its ancestral habitat (exaptations). Our data finally support the conservatism hypothesis of ecological evolutionary change (Funk and Brooks 1990). The scenarios constructed for morphological structures involved in acoustic and mating behavior show that their evolution is complex and probably the result of several factors. Data at hand do not allow to test the role of predation, and suggest that the habitat could influence the acoustic and mating behavior by modifying the structure of interindividual interactions. It is hypothesized that the physical structure and spatial distribution of habitat could be most important.