Search results for "POISON FROG"
showing 6 items of 6 documents
Geographic mosaic of selection by avian predators on hindwing warning colour in a polymorphic aposematic moth
2020
AbstractWarning signals are predicted to develop signal monomorphism via positive frequency-dependent selection (+FDS) albeit many aposematic systems exhibit signal polymorphism. To understand this mismatch, we conducted a large-scale predation experiment in four locations, among which the frequencies of hindwing warning coloration of aposematic Arctia plantaginis differ. Here we show that selection by avian predators on warning colour is predicted by local morph frequency and predator community composition. We found +FDS to be strongest in monomorphic Scotland, and in contrast, lowest in polymorphic Finland, where different predators favour different male morphs. +FDS was also found in Geo…
Mind the gap: Treefalls as drivers of parental trade-offs
2015
Abstract Tree‐fall gaps are small‐scale disturbances whose formation, colonization, and role in forest dynamics are well documented, but whose effects on animal ecology are still greatly overlooked, except for studies comparing species richness of gaps 6+ months old to that in the closed canopy. Other factors associated with the invasion of fresh tree‐fall gaps such as animal breeding adaptations have been largely neglected. I studied the immediate (within hours and days) arrival of the poison frog Dendrobates tinctorius in new tree‐fall gaps to examine the dynamics of their invasion in relation to tadpole rearing. I found that rearing sites are occupied sooner and tadpoles deposited at hig…
Diversity in warning coloration: selective paradox or the norm?
2019
Aposematic theory has historically predicted that predators should select for warning signals to converge on a single form, as a result of frequency-dependent learning. However, widespread variation in warning signals is observed across closely related species, populations and, most problematically for evolutionary biologists, among individuals in the same population. Recent research has yielded an increased awareness of this diversity, challenging the paradigm of signal monomorphy in aposematic animals. Here we provide a comprehensive synthesis of these disparate lines of investigation, identifying within them three broad classes of explanation for variation in aposematic warning signals: …
Pool choice in a vertical landscape: Tadpole‐rearing site flexibility in phytotelm‐breeding frogs
2021
Abstract Many species of Neotropical frogs have evolved to deposit their tadpoles in small water bodies inside plant structures called phytotelmata. These pools are small enough to exclude large predators but have limited nutrients and high desiccation risk. Here, we explore phytotelm use by three common Neotropical species: Osteocephalus oophagus, an arboreal frog that periodically feeds eggs to its tadpoles; Dendrobates tinctorius, a tadpole‐transporting poison frog with cannibalistic tadpoles; and Allobates femoralis, a terrestrial tadpole‐transporting poison frog with omnivorous tadpoles. We found that D. tinctorius occupies pools across the chemical and vertical gradient, whereas A. fe…
Paradox lost: variable colour-pattern geometry is associated with differences in movement in aposematic frogs
2014
Aposematic signal variation is a paradox: predators are better at learning and retaining the association between conspicuousness and unprofitability when signal variation is low. Movement patterns and variable colour patterns are linked in non-aposematic species: striped patterns generate illusions of altered speed and direction when moving linearly, affecting predators' tracking ability; blotched patterns benefit instead from unpredictable pauses and random movement. We tested whether the extensive colour-pattern variation in an aposematic frog is linked to movement, and found that individuals moving directionally and faster have more elongated patterns than individuals moving randomly and…
Mind the gap: Treefalls as drivers of parental trade-offs
2015
Tree-fall gaps are small-scale disturbances whose formation, colonization, and role in forest dynamics are well documented, but whose effects on animal ecology are still greatly overlooked, except for studies comparing species richness of gaps 6+ months old to that in the closed canopy. Other factors associated with the invasion of fresh tree-fall gaps such as animal breeding adaptations have been largely neglected. I studied the immediate (within hours and days) arrival of the poison frog Dendrobates tinctorius in new tree-fall gaps to examine the dynamics of their invasion in relation to tadpole rearing. I found that rearing sites are occupied sooner and tadpoles deposited at higher rates…