Metamorphosis and the transition from larvae or embryos to juveniles in
fishes are important in order to answer, for example, questions about:
(1) life-history styles and their modifications in evolutionary
perspective and within current environmental demands; (2) the
development and application of fisheries recruitment models, (3) the use
of ontogenetic scales for interspecific comparisons, (4) the
identification of ontogenetic shifts in resource use, and (5) the
discovery of evolutionary interrelationships of species or genera. This
volume is dedicated to recent studies and reviews of existing knowledge
on this insufficiently-addressed area of ichthyology. Most of the papers
in this volume were presented in Bratislava, Slovakia, at the 1st
International Workshop of the Fish Ontogeny Network of Europe (FONE) in
September 1997, a meeting sponsored in part by the European Commission.
This volume emphasizes an integrated approach to the study of fish
ontogeny, which is a process during which one event is related to
another and everything is related to everything else, encompassing
physiology, morphology, behaviour and niche. Within this comprehensive
perspective, the papers in this volume are grouped along four major
themes: reflections on early ontogeny and metamorphosis,
organism-environment relationships, ontogeny of predator-prey
interactions, and behaviour and ontogeny. Among other issues, the papers
consider topics such as whether one can identify when fish metamorphosis
ends, whether the larva period begins with hatching or with the onset of
exogenous feeding, whether fish ontogeny is `saltatory' or `gradual',
and whether larvae are eliminated in some fishes with direct
development. The keynote paper of this volume reviews the main topics
within contemporary paradigms and the final paper concludes that the
onset of the juvenile period can be identified in some species, but
precision remains problematic, emphasizing the need for further research
in this dynamic area of fish biology.
