CALL EVOLUTION IN NEOBATRACHUS (ANURA, MYOBATRACHIDAE) - SPECULATIONSON TETRAPLOID ORIGINS

Four species of the Australian burrowing frog Neobatrachus are tetrapl oid and another six are diploid. The origins of the tetraploids are un known. I describe advertisement calls of all 10 species and compare th ose of diploids and tetraploids. Calls of diploids can all be easily d istinguished. All four tetraploids have calls with low pulse numbers a nd low pulse rates: broadly similar to calls of the diploid N. fulvus. The calls of N. kunapalari differ in three properties from those of t he other three tetraploid species, N. aquilonius, N. centralis, and N. sudelli. I examined four models to account for call evolution in this genus. Calls of tetraploids may be unaltered from those of their dipl oid parents, have a forced change imposed by cell characteristics asso ciated with doubling of the chromosome set, have evolved from an inter action (reproductive character displacement) with diploid parents, or have a hybrid structure derived from an allotetraploid origin. Under e ach model, I offer predictions of relationships of Neobatrachus specie s that must be further tested with an adequate phylogenetic analysis b ased on independent characters.