ABSTRACT

The earliest stages of life can be the most vulnerable. This is when vast changes occur, as a new individual proceeds through a program of development from a single cell to a multicellular organism with tissues and organs. Differentiation into muscles, sense organs, nervous tissue, and blood all takes place while the embryo is unable to move independently to escape a difficult environment or avoid predation. Beach-spawning fishes oviposit in the intertidal zone, a highly variable environment that is ruled by tidal cycles of inundation and air exposure. Placing one of the most vulnerable stages of life in this zone of constant change is a deliberate choice that deserves some careful examination. This chapter focuses on the effects of beach spawning on the early life of the many diverse species of fishes with these amphibious embryos.