Size, Scaling, and the Evolution of Complex Life Cycles

“…density, desiccation, pre-dation risk and food availability have been shown to significantly affect larval development (Wilbur and Collins, 1973; Werner, 1988; Van Buskirk and McCollum, 2000; Day and Rowe, 2002; Alcobendas, Buckley and Tejedo, 2004; Weitere et al., 2004; Eitam, Blaustein and…”

“Adaptations to environmental factors also occur in less mobile life stages, such as eggs or larvae, as physiological tolerances are often size-specific in fishes (Werner 1988).”

“1989) and because ontogenetic shifts represent the mode of life in 80% of animal taxa (Werner 1988), similar phenomena are likely to occur in many other IGP systems.”

“Like the toads and the butterflies of the world, more than 80% of animals on Earth exhibit an ontogenetic niche shift (Werner, 1988), though not all require dramatic metamorphosis to do so.”

“In many species, individuals grow in size during a significant part of their life (Werner, 1988; Ebenman and Persson, 1988).”

“Since different food types often require different morphologies to be efficiently used, species with an ontogenetic diet shift may face a trade-off between performance early and late in life [38,44].”

“Even though some species, including humans, have direct development, metamorphosis is the dominant life-history strategy in the animal kingdom (Werner 1988).”

“However, growth rate and mortality risk in the larval phase have to be balanced against these variables in the terrestrial phase (Werner, 1986, 1988), and there are no data about growth rate and mortality risk of postmetamorphic Aglyptodactylus.”

“The importance of considering the ecological implications of intraspecific size variation is further justified by the fact that the overwhelming majority of the earth’s taxa exhibit some degree of size/stage structure (Werner 1988).”

“This question is especially relevant when different ontogenetic stages of an animal exhibit different morphologies and use diverse ecological niches and habitats (Werner 1988; Kelleher et al.”

“There is agreement about defining metamorphosis as a sudden drastic change in morphology during postembryonic development which coincides with a change in habitat, lifestyle and mode of feeding or resource requirements (Bishop et al., 2006; Passano, 1961; Werner, 1988).”

“The majority of all animal species fall within these two cat‐ egories, with the exception of most birds and mammals (Werner, 1988; Werner & Gilliam, 1984; Wilbur, 1980).”

“Understanding a species requires comprehending its entire life history, not just the morphological and ecological features attendant to the adult (Werner & Gilliam, 1984; Werner, 1988).”

“As body size governs a majority of individual vital rates such as foraging, consumption, mortality and reproduction (Werner, 1988; Woodward et al., 2005), the change in body size during ontogeny leads to a striking size-dependency of life history.”

“Keywords: metamorphosis, hormones, genetic accommodation, climate change, plasticity THE ROLE OF HORMONES IN METAMORPHOSIS Approximately 80% of animals undergo metamorphosis—the transition from a larval to an adult stage (Figure 1; Werner, 1988).”

“The importance of body size is related to the fact that 80% of all species grow and develop throughout their entire life (Werner, 1998).”

“In marine ecosystems, most fi sh species have life histories with two distinct phases, a dispersive pelagic larval phase and a relatively sedentary benthic juvenile and adult phase (see Werner, 1988, for review).”

“2010; Werner 1988).”

“CLC animals are those that face an abrupt habitat shift as they go through different developmental stages and so they may be exposed to radically different ecological conditions and stressors (Werner, 1988).”

“I note that q is exactly the quantity that is minimized in the well-known ‘minimize l ⁄ g’ rule of Werner & Gilliam (1984), concerning optimal decisions such as niche shifts and timing of metamorphosis (see also Werner, 1988; Ludwig & Rowe, 1990; Houston et al., 1993).”

“In animals, many species - rich groups have complex life cycles, such as amphibians, crustaceans, mollusks, and some of the most species - rich orders of arthropods, including Coleoptera, Hymenoptera, and Lepidoptera ( 11 – 13 ).”

“Ecological transitions, such as migratory birds and fish moving to new biomes or insects and amphibians undergoing metamorphosis, result in new suites of abiotic conditions and biotic interactions for the organisms, separating resources in space and/or time (Wilbur 1980; Werner 1988).”

“Most animals experience indirect development, undergoing metamorphosis that radically alters the phenotypes and function of the larval and adult forms in different ecological settings (Werner, 1988).”

“…size spectra (relationship between mass and abundance) as well as the marine food web interactions and food web structure (Werner & Gilliam, 1984; Werner, 1988; Williams & Martinez, 2000; Dunne et al., 2002; Woodward & Hildrew, 2002; Hartvig et al., 2011; Jacob et al., 2011; Blanchard et al.,…”

“Environmental conditions experienced by unique life stages are particularly disparate among the 80% of species on Earth that exhibit complex life cycles (Werner 1988), wherein distinct life stages often rely on entirely different ecosystems (Wilbur 1980).”

“298 299 Attack rate, as a function of predator size, has been known to be dome shaped (Aljetlawi et al. 2004; 300 Tripet and Perrin, 1994; Werner, 1988).”

“Anurans have a complex life cycle, in which they develop sequentially into distinct morphological forms that are accompanied by changes in ecological niche (Wilbur, 1980; Werner, 1988).”

“The increases in size and improved condition of a fish depend on the availability, quality, and quantity of food (Werner 1988).”

“For most organisms their size, rather than age, determines their fecundity (McGraw & Wulff 1983) and survival probabilities (Werner 1988).”

“Such ontogenetic diet shifts are widespread in nature (Werner 1988; Werner and Gilliam 1984) and influence the conditions for coexistence by altering where in the life cycle density-dependent regulation occurs, which determines whether species can persist together (Schellekens et al. 2010).”

“Fishes change habitats or prey types during their ontogeny, and they are often exposed to the selection pressure on important morphological and behavioral traits at different life stages (Werner 1988).”

“The genetic decoupling hypothesis for the evolution of complex life cycles (Werner 1988; Ebenman 1992; Moran 1994; Aguirre et al.”

“…the phenotypic traits related to fitness that are expressed at different life stages, thereby allowing post-metamorphic stages to evolve independently from pre-metamorphic ones and reducing inter-stage competition (Istock, 1967; Werner, 1988; Ebenman, 1992; Moran, 1994; Ten Brink et al., 2019).”

“Given that over 80% of described animal species have complex life histories ( Werner, 1988 ; Phung et al., 2020 ), and current conservation programs heavily rely on adult information ( Faria et al., 2021 ), our study suggests that neglecting the vulnerability of non-adult stages may lead to a…”

“These life cycles are the ones most common among animals (Werner, 1988; Rumrill et al., 2018; Saltini et al., 2023), and marine invertebrates are no exception to this, encompassing various developmental stages adapted to different ecological roles and environmental conditions (Gibson, 2011; Iwasa…”

“This is especially true for those which undergo dramatic ontogenetic shifts in habitat between juvenile and adult stages (Moll & Brown, 2008 ; Werner, 1988), as this can often lead to differing competitive strategies between life stages (Bissattini et al., 2019).”