Lifetime Fitness, Sex-Specific Life History, and the Maintenance of a Polyphenism
Abstract
Polyphenisms-alternative morphs produced through plasticity-can reveal the evolutionary and ecological processes that initiate and maintain diversity within populations. We examined lifetime fitness consequences of two morphs in a polyphenic population of Arizona tiger salamanders using a 27-year data set with 1,317 adults and 6,862 captures across eight generations. Larval salamanders develop into either an aquatic paedomorph that retains larval traits and stays in its natal pond or a terrestrial metamorph that undergoes metamorphosis. To evaluate the adaptive significance of this polyphenism, we compared lifetime reproductive success of each morph and assessed how life-history strategies and spatiotemporal variation explained fitness. We found sex-specific differences in lifetime fitness between morphs. For males, paedomorphs had more reproductive opportunities than metamorphs when we accounted for the potential mating advantage of larger males. For females, in contrast, metamorphs had higher estimated egg production than paedomorphs. Life-history strategies differed between morphs largely because the morphs maximized different ends of the trade-off between age at first reproduction and longevity. Spatiotemporal variation affected larval more than adult life-history traits, with little to no effect on lifetime fitness. Thus, environmental variation likely explains differences in morph production across time and space but contributes little to lifetime fitness differences between morphs and sexes. Our long-term study and measures of lifetime fitness provide unique insight into the complex selective regimes potentially acting on each morph and sex. Our findings motivate future work to examine how sex-specific selection may contribute to the maintenance of polyphenism.
Local Knowledge Graph (24 entities)
Related Works
Items connected by shared entities, co-authorship, citations, or semantic similarity.
Data from: Lifetime fitness, sex-specific life history, and the maintenance of a polyphenism
The role of environmental variation in mediating fitness trade-offs for an amphibian polyphenism
Larval growth in polyphenic salamanders: making the best of a bad lot
Polyphenism predicts actuarial senescence and lifespan in tiger salamanders
Data from: Individual life histories: Neither slow nor fast, just diverse
Carry-over effects of larval food stress on adult energetics and life history in a nectar-feeding butterfly
Fish Passage Restoration Stream Habitat Restoration Guidelines: Final Draft
Some Factors Historically Affecting The Distribution and Abundance of Fishes In The Gunnison River
Chubs in the Tub: Colorado's Native Aquatic Species Restoration Facility
Cited By (12 times, 10 in Knowledge Hub)
Effects of elevation on salamander life strategies
Females know best: dispersal polymorphism maintained by sex-specific foraging
Polyphenism predicts actuarial senescence and lifespan in tiger salamanders
Climate mediates the trade-offs associated with phenotypic plasticity in an amphibian polyphenism
The role of environmental variation in mediating fitness trade-offs for an amphibian polyphenism
Cross-trophic-level dynamics in aquatic ecosystems and their application across ecological contexts
Efficacy and Uses of PIT Tag Telemetry in Salamanders From the Western USA: ,<i> Aneides vagrans </i>, <i> Ensatina eschscholtzii </i>, and <i> Ambystoma mavortium </i>
Effects of a range-shifting caddisfly on life histories of a top predator in high elevation ponds
Morph and Sex differences in prey selectivity of tiger salamanders (<i> Ambystoma mavortium nebulosum </i>)
Morph- and sex-specific differences in corticosterone of Arizona tiger salamanders (<i>Ambystoma mavortium nebulosum</i>)
References (93)
8 in Knowledge Hub, 85 external
