Carry-over Effects of Size at Metamorphosis in Red-eyed Treefrogs: Higher Survival but Slower Growth of Larger Metamorphs

Biotropica ◽  
2015 ◽  
Vol 47 (2) ◽  
pp. 218-226 ◽  
Author(s):  
Rebecca D. Tarvin ◽  
Catalina Silva Bermúdez ◽  
Venetia S. Briggs ◽  
Karen M. Warkentin
Keyword(s):  
Size At Metamorphosis ◽  
Carry Over

scholarly journals Consequences of life history switch point plasticity for juvenile morphology and locomotion in theTúngara frog

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1268 ◽  
Author(s):  
Julie F. Charbonnier ◽  
James R. Vonesh
Keyword(s):  
Life History ◽  
Laboratory Experiment ◽  
Water Depth ◽  
Aquatic Organisms ◽  
Life Cycles ◽  
Jumping Performance ◽  
Larval Amphibians ◽  
Size At Metamorphosis ◽  
Dry Down ◽  
Carry Over

Many animals with complex life cycles can cope with environmental uncertainty by altering the timing of life history switch points through plasticity. Pond hydroperiod has important consequences for the fitness of aquatic organisms and many taxa alter the timing of life history switch points in response to habitat desiccation. For example, larval amphibians can metamorphose early to escape drying ponds. Such plasticity may induce variation in size and morphology of juveniles which can result in carry-over effects on jumping performance. To investigate the carry-over effects of metamorphic plasticity to pond drying, we studied the Túngara frog,Physalaemus pustulosus, a tropical anuran that breeds in highly ephemeral habitats. We conducted an outdoor field mesocosm experiment in which we manipulated water depth and desiccation and measured time and size at metamorphosis, tibiofibula length and jumping performance. We also conducted a complimentary laboratory experiment in which we manipulated resources, water depth and desiccation. In the field experiment, metamorphs from dry-down treatments emerged earlier, but at a similar size to metamorphs from constant depth treatments. In the laboratory experiment, metamorphs from the low depth and dry-down treatments emerged earlier and smaller. In both experiments, frogs from dry-down treatments had relatively shorter legs, which negatively impacted their absolute jumping performance. In contrast, reductions in resources delayed and reduced size at metamorphosis, but had no negative effect on jumping performance. To place these results in a broader context, we review past studies on carry-over effects of the larval environment on jumping performance. Reductions in mass and limb length generally resulted in lower jumping performance across juvenile anurans tested to date. Understanding the consequences of plasticity on size, morphology and performance can elucidate the linkages between life stages.

Anuran developmental plasticity loss: the cost of constant salinity stress

2015 ◽  
Vol 63 (5) ◽  
pp. 331 ◽  
Author(s):  
Brian D. Kearney ◽  
Phillip G. Byrne ◽  
Richard D. Reina
Keyword(s):  
Developmental Plasticity ◽  
Freshwater Wetlands ◽  
Complex Life Cycle ◽  
Tree Frog ◽  
Salinity Treatment ◽  
Secondary Salinisation ◽  
Elevated Salinity ◽  
Size At Metamorphosis ◽  
Source Populations ◽  
Carry Over

In animals with a complex life cycle, changes in biotic and abiotic conditions during development can alter growth and maturation rates, causing carry-over effects in postmetamorphic phenotypes. In anurans, this developmental plasticity can result in a trade-off between length of larval period and body size at metamorphosis in stressful environments. Secondary salinisation has been identified as a substantial stressor to amphibians; however, little is known about how salinity-induced developmental plasticity differs between anuran populations. We examined differences in survival, time to metamorphosis, size at metamorphosis (mass and snout–vent length) and body condition at metamorphosis in response to elevated salinity in three populations of the brown tree frog (Litoria ewingii). Significant differences in size at metamorphosis between salinity treatments were observed in tadpoles sourced from freshwater wetlands and ephemeral wetlands, with tadpoles showing a reduced mass and snout–vent length at metamorphosis in the higher-salinity treatment. There were no significant differences in metamorphic traits between salinity treatments in tadpoles sourced from a consistently brackish wetland, suggesting either an erosion of developmental plasticity in response to elevated salinity, or the magnitude of salinity required to alter developmental traits is higher in this population. Our results indicate that environmental conditions of source populations need to be considered when studying life-history adaptations in response to environmental change.

scholarly journals Carry-over effects of the larval environment on the post-metamorphic performance of Bombina variegata (Amphibia, Anura)

2020 ◽  
pp. 126-134 ◽  
Author(s):  
Ulrich Sinsch
Keyword(s):  
Body Condition ◽  
Life History Theory ◽  
Developmental Rate ◽  
Independent Effect ◽  
Initial Stimulus ◽  
Breeding Sites ◽  
Size At Metamorphosis ◽  
Permanent Pond ◽  
Bombina Variegata ◽  
Carry Over

Metamorphs of the yellow-bellied toad, Bombina variegata, vary widely in size at metamorphosis in the field. We performed a replicated outdoor mesocosm study to simulate the environmental factor combinations in permanent and ephemeral breeding sites and to quantify their effects on tadpole development (duration of the larval period, metamorph size and body condition). Looking for potential carry-over effects of the larval environment, we quantified locomotor performance of all metamorph phenotypes originating from the mesocosms immediately after metamorphosis under controlled conditions. In contrast to the prediction of life-history theory, tadpoles were unable to adjust developmental rate to water availability, but metamorphs originating from the ephemeral pond treatment were smaller and had a lower body condition than those from the permanent pond treatment. Size-dependent carry-over effects included the length of the first jump following tactile stimulation, burst performance (total length of spontaneous jumps) and endurance (total distance covered in 10 forced jumps). A size-independent effect of larval environment was the prolonged locomotor effort to escape (5.7 consecutive jumps following initial stimulus) of metamorphs from the ephemeral pond treatment compared to same-sized ones (3.7 jumps) from the permanent pond treatment. Thus, we demonstrate that carry-over effects of larval environment on metamorph phenotype and behaviour cause a considerable variation in fitness in the early terrestrial stage of B. variegata. Informed conservation management of endangered populations in the northern range should therefore include the provision of small permanent breeding ponds promoting larger and fitter metamorphs.

Minimizing Carry-Over Effects After Treatment Failure and Maximizing Therapeutic Outcome

2014 ◽  
Vol 222 (3) ◽  
pp. 171-178 ◽  
Author(s):  
Mareile Hofmann ◽  
Nathalie Wrobel ◽  
Simon Kessner ◽  
Ulrike Bingel
Keyword(s):  
Treatment Failure ◽  
Human Subjects ◽  
Subsequent Treatment ◽  
Clinical Samples ◽  
Administration Route ◽  
Healthy Human ◽  
Negative Experiences ◽  
Analgesic Treatment ◽  
Balanced Design ◽  
Carry Over

According to experimental and clinical evidence, the experiences of previous treatments are carried over to different therapeutic approaches and impair the outcome of subsequent treatments. In this behavioral pilot study we used a change in administration route to investigate whether the effect of prior treatment experience on a subsequent treatment depends on the similarity of both treatments. We experimentally induced positive or negative experiences with a topical analgesic treatment in two groups of healthy human subjects. Subsequently, we compared responses to a second, unrelated and systemic analgesic treatment between both the positive and negative group. We found that there was no difference in the analgesic response to the second treatment between the two groups. Our data indicate that a change in administration route might reduce the influence of treatment history and therefore be a way to reduce negative carry-over effects after treatment failure. Future studies will have to validate these findings in a fully balanced design including larger, clinical samples.

Does CBT for Psychosis Have an Impact on Delusions by Improving Reasoning Biases and Negative Self-Schemas?

2018 ◽  
Vol 226 (3) ◽  
pp. 152-163 ◽  
Author(s):  
Stephanie Mehl ◽  
Björn Schlier ◽  
Tania M. Lincoln
Keyword(s):  
Behavioral Therapy ◽  
Theoretical Models ◽  
Self Esteem ◽  
Secondary Outcome ◽  
Intervention Effect ◽  
Produce Change ◽  
Attribution Biases ◽  
Carry Over ◽  
Implicit And Explicit ◽  
Reasoning Biases

Abstract. Cognitive-behavioral therapy for psychosis (CBTp) builds on theoretical models that postulate reasoning biases and negative self-schemas to be involved in the formation and maintenance of delusions. However, it is unclear whether CBTp induces change in delusions by improving these proposed causal mechanisms. This study reports on a mediation analysis of a CBTp effectiveness trial in which delusions were a secondary outcome. Patients with psychosis were randomized to individualized CBTp (n = 36) or a waiting list condition (WL; n = 34). Reasoning biases (jumping to conclusions, theory of mind, attribution biases) and self-schemas (implicit and explicit self-esteem; self-schemas related to different domains) were assessed pre- and post-therapy/WL. The results reveal an intervention effect on two of four measures of delusions and on implicit self-esteem. Nevertheless, the intervention effect on delusions was not mediated by implicit self-esteem. Changes in explicit self-schemas and reasoning biases did also not mediate the intervention effects on delusions. More focused interventions may be required to produce change in reasoning and self-schemas that have the potential to carry over to delusions.

Investigation on the control of multiphase flow behavior in a continuous casting tundish during ladle change

2020 ◽  
Vol 117 (6) ◽  
pp. 619
Author(s):  
Rui Xu ◽  
Haitao Ling ◽  
Haijun Wang ◽  
Lizhong Chang ◽  
Shengtao Qiu
Keyword(s):  
Multiphase Flow ◽  
Flow Behavior ◽  
Rolled Strip ◽  
Impact Zone ◽  
Steel Cleanliness ◽  
Carry Over ◽  
Slag Carry Over ◽  
Hot Rolled ◽  
Turbulence Inhibitor ◽  
The Impact

The transient multiphase flow behavior in a single-strand tundish during ladle change was studied using physical modeling. The water and silicon oil were employed to simulate the liquid steel and slag. The effect of the turbulence inhibitor on the slag entrainment and the steel exposure during ladle change were evaluated and discussed. The effect of the slag carry-over on the water-oil-air flow was also analyzed. For the original tundish, the top oil phase in the impact zone was continuously dragged into the tundish bath and opened during ladle change, forming an emulsification phenomenon. By decreasing the liquid velocities in the upper part of the impact zone, the turbulence inhibitor decreased considerably the amount of entrained slag and the steel exposure during ladle change, thereby eliminating the emulsification phenomenon. Furthermore, the use of the TI-2 effectively lowered the effect of the slag carry-over on the steel cleanliness by controlling the movement of slag droplets. The results from industrial trials indicated that the application of the TI-2 reduced considerably the number of linear inclusions caused by ladle change in hot-rolled strip coils.

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