Ss. Crawford et Ek. Balon, ALTERNATIVE LIFE-HISTORIES OF THE GENUS LUCANIA .3. AN ECOMORPHOLOGICAL EXPLANATION OF ALTRICIAL (L-PAPVA) AND PRECOCIAL (L-GOODEI) SPECIES, Environmental biology of fishes, 41(1-4), 1994, pp. 369-402
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.