ALTERNATIVE LIFE-HISTORIES OF THE GENUS LUCANIA .3. AN ECOMORPHOLOGICAL EXPLANATION OF ALTRICIAL (L-PAPVA) AND PRECOCIAL (L-GOODEI) SPECIES

Important differences were observed in the early ontogenies of Lucania parva. and Lucania goodei. These differences can be explained in term s of the altricial-precocial model of speciation. Lucania parva can be recognized as an altricial form that produces many eggs with relative ly little yolk investment, compared to the more precocial L. goodei. M any of the differences observed in embryo, larva and juvenile specimen s appear to be related to these differences in gamete investment. Acce lerated developmental rates in the precocial form suggest that paedomo rphosis is an important proximate mechanism in the bifurcation of alte rnative life-history styles in this genus. Some morphological characte ristics, such as vitelline circulation and body shape, may be transfor mations associated with the particular environmental conditions in whi ch the animals must develop and survive. Our observations suggest that these two species in the genus Lucania have followed different ontoge nic trajectories in response to prevailing environmental conditions.