The Effect of Conspecific Interactions on Metamorphosis in Bufo Americanus

Abstract

Toad tadpoles (genus Bufo) form large, socially interacting premetamorphic and post—metamorphic swarms. Within premetamorphic aggregates tadpoles compete, and larger tadpoles negatively affect the growth of smaller ones. We hypothesized that increased conspecific interaction during development could facilitate metamorphic synchrony, and therefore we tested the effects of the level of conspecific interaction on the means and variances of the number of days to metamorphosis and mass at metamorphosis. Bufo americanus tadpoles were randomly assigned to three interaction treatments: Isolated cups, Partially Interacting aquaria (screened partitions), and Fully Interacting aquaria (no partitions). Food and density were held constant across treatments. Our results demonstrated: (1) increased conspecific interaction may increase variation in the number of days to metamorphosis, therefore decreasing metamorphic synchrony, and (2) increased interaction increases mass at metamorphosis. See full-text article at JSTOR