Early fish development has been described as a continuous process of growth and differentiation. However, comparative studies have long shown that survival, performance, and variability are not consistently distributed across ontogeny, but instead concentrate around discrete developmental transitions (Blaxter, 1988). Building on the concept of saltatory ontogeny proposed by Balon (1979, 2001), we argue that early ontogeny proceeds through a sequence of ontogenetic jumps, each characterized by abrupt changes in functional priorities and energetic demand rather than gradual change. These transitions include cell division and axis formation, massive reorganization during gastrulation, costly task allocation during organogenesis, hatching as the completion of basic functional assembly, activation of integrated systems at mouth opening, the critical energetic transition at first feeding, subsequent refinement of visual, digestive, and locomotor tools, and finally complete metamorphosis. We propose that the capacity of red snapper to cross these ontogenetic jumps successfully is constrained by the egg’s energetic architecture, particularly the balance between endogenous reserves and emerging metabolic demand. In this framework, red snapper larval development is not a race toward size but a sequence of energetic tests in which the efficiency of energy use, rather than absolute energy content, determines how far a larva can progress along its developmental trajectory.