Amphibian Metamorphosis: Growth Rate, Predation Risk, and the Optimal Size at Transformation

1986 ◽  
Vol 128 (3) ◽  
pp. 319-341 ◽  
Author(s):  
Earl E. Werner
Keyword(s):  
Growth Rate ◽  
Predation Risk ◽  
Optimal Size ◽  
Amphibian Metamorphosis

scholarly journals Relationship between habitat distribution, growth rate, and plasticity in congeneric larval dragonflies

2005 ◽  
Vol 83 (8) ◽  
pp. 1128-1133 ◽  
Author(s):  
S J McCauley
Keyword(s):  
Growth Rate ◽  
Predation Risk ◽  
Growth Rates ◽  
Lepomis Macrochirus ◽  
Negative Relationship ◽  
Activity Level ◽  
Activity Levels ◽  
Habitat Distribution ◽  
Invertebrate Predators ◽  
The Relationship

The relationship between habitat distribution, growth rate, and plasticity was examined in the larvae of three species of dragonfly in the genus Libellula L., 1758. Growth rates were compared under three conditions: in the absence of predation risk, in the presence of sunfish (Lepomis macrochirus Rafinesque, 1819; Pisciformes: Centrachidae), and in the presence of invertebrate predators. I assessed how the habitat distributions of the three species of dragonfly, specifically how commonly they occur with fish, were related to growth rates and to the level of growth plasticity under different levels of perceived predation risk. There was a negative relationship between growth rate and the frequency with which species coexist with sunfish. Growth-rate plasticity was limited and does not appear to be important in determining the ability of species to coexist with alternative top predator types. Only one species exhibited growth-rate plasticity, decreasing growth in response to the predator with which it most commonly coexists but not to the species which poses the greatest predation risk. A comparison of growth rates and activity levels in the presence and absence of these predators suggests that growth and activity level parallel each other in these species.

scholarly journals Designing of Parking Spaces on Parking Taking into Account the Parameters of Design Vehicles

Computation ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 71
Author(s):  
Miroslava Mikusova ◽  
Jamshid Abdunazarov ◽  
Joanna Zukowska ◽  
Juraj Jagelcak
Keyword(s):  
Growth Rate ◽  
Small Towns ◽  
Optimal Number ◽  
Transportation Infrastructure ◽  
Optimal Size ◽  
Parking Space ◽  
Optimal Parameters ◽  
Passenger Cars ◽  
Parking Place

Nowadays, in all cities, there is an acute problem of a lack of parking spaces. The number of vehicles is constantly increasing not only in big cities and megacities, but also in small towns of the country, and there are not enough parking places—the pace of solving the problem is several times slower than the growth rate of transport among citizens. The paper is dedicated to the determination of an optimal size of a parking place for design vehicles in a parking space as an element of roads. In the example of passenger cars and trucks, the optimal number of parking places is presented. The results of the research on the dimensioning of parking spaces serve as recommendations and can be used for the design of objects of transportation infrastructure. According to the research, authors introduce the term “design vehicle” and provide its definition. They also figure out optimal parameters for each design vehicle and recommend a special template for designing parking places.

scholarly journals FORECASTING CHANGES IN THE STRUCTURE OF ASSETS AND CAPITAL OF AGRICULTURAL ENTERPRISES

2021 ◽  
Vol 6 (2) ◽  
pp. 52-57
Author(s):  
Nataliia Barabash ◽  
Tetiana Pashkuda
Keyword(s):  
Growth Rate ◽  
Agricultural Sector ◽  
Maximum Level ◽  
Management Policy ◽  
Optimal Size ◽  
Working Capital ◽  
Agricultural Enterprises ◽  
Study Results ◽  
Land Relations ◽  
Retained Earnings

The purpose of the study is to develop methodological approaches to forecasting changes in the structure of assets and capital of agricultural enterprises. Methodology. The information base of the article is presented by scientific works of domestic and foreign scientists. The research is based on scientific methods, among which it is expedient to distinguish: analysis and synthesis, comparison, idealization, and abstraction, as well as systematization and generalization – during the formulation of conclusions as a result of the study. Results. It is established that the agricultural sector of Ukraine has significant potential for further growth, but a number of problems hinder its development. Today, the stimulus is the system of land use and land relations, put into effect by lifting the moratorium on land sales. At present, the consequences of such reforms are unpredictable, as there are no clear and transparent rules of the «game» in the sector. It is found out that the most powerful participants in the agricultural market are agricultural holdings, which determine one of the goals of their activities is the development of infrastructure and expansion of influence in foreign markets. In modern economic conditions, the agricultural sector brings 15-20% of Ukraine's GDP annually, and despite the crisis of recent years, provides the population with high-quality products of its own production. Practical implications. One of the main problems in the implementation of working capital management policy is to determine the required amount and optimal composition, which is able to ensure the continuity of the enterprise, the maximum level of efficiency of funds. These problems are solved by forecasting the structure of working capital and forecasting its optimal amount. The urgency of the issue increases due to the fact that the problem of predicting the optimal size and structure of assets and capital challenges is caused by macroeconomic and macro-financial instability. Value/originality. Methodical approaches to forecasting changes in the structure of assets and capital are considered. It is proposed to use a system of indicators for calculations, including the following: growth rate of production and sales, a growth rate of product prices, projected operating costs, non-current assets at the beginning of the forecast period, projected investment, average depreciation rate of non-current assets, duration of production turnover inventories, the duration of collection of receivables, the average share of retained earnings in total profit from sales, the basic volume of production and sales, registered and annual invested capital of the enterprise.

scholarly journals Estimating Optimal Level of Taxation for Growth Maximization in Asia

2017 ◽  
Vol 4 (3) ◽  
pp. 47 ◽  
Author(s):  
Jeeban Amgain
Keyword(s):  
Growth Rate ◽  
Panel Data ◽  
Optimal Level ◽  
Quadratic Model ◽  
Tax Revenue ◽  
Optimal Size ◽  
Asian Countries ◽  
Growth Maximization ◽  
Quadratic Models ◽  
Unbalanced Panel Data

What level of tax revenue in GDP is suitable for a country to maximize the growth rate in Asia? To address this question, this paper estimates the optimal size of taxes which maximizes growth rate, using Scully and quadratic models, from the unbalanced panel data of 32 Asian countries. Both methods approve that tax revenue around 18 percent of GDP maximizes the growth rate. However, quadratic model provides more consistent result than the Scully model. Most importantly, the findings clearly show the existence of inverse U-shaped relationship between taxes and growth.

Optimal staffing of a forest fire fighting organization

1984 ◽  
Vol 14 (4) ◽  
pp. 589-594
Author(s):  
Yash P. Aneja ◽  
Mahmut Parlar
Keyword(s):  
Growth Rate ◽  
Sensitivity Analysis ◽  
Forest Fire ◽  
Fire Fighting ◽  
Optimal Size ◽  
Fire Occurrence ◽  
Nonlinear Programming Problem ◽  
Fire Growth ◽  
Probability Densities ◽  
Nonnegativity Constraints

This paper deals with finding the optimal size of a forest fire fighting organization. Fire occurrence and fire growth rate are assumed to be random variables with given probability densities. An objective function representing the expected cost is developed by using probabilistic arguments. The resulting nonlinear programming problem with nonnegativity constraints is solved and an extensive sensitivity analysis is presented for cost related and noncost parameters of the problem.

GROWTH RATE VARIATION AMONG PASSERINE SPECIES IN TROPICAL AND TEMPERATE SITES: AN ANTAGONISTIC INTERACTION BETWEEN PARENTAL FOOD PROVISIONING AND NEST PREDATION RISK

Evolution ◽  
2011 ◽  
Vol 65 (6) ◽  
pp. 1607-1622 ◽  
Author(s):  
Thomas E. Martin ◽  
Penn Lloyd ◽  
Carlos Bosque ◽  
Daniel C. Barton ◽  
Atilio L. Biancucci ◽  
...  
Keyword(s):  
Growth Rate ◽  
Predation Risk ◽  
Nest Predation ◽  
Rate Variation ◽  
Food Provisioning ◽  
Antagonistic Interaction ◽  
Passerine Species

Optimal Size of China’s Fiscal Expenditure and Policy Evaluation: 1978-2006

2011 ◽  
Vol 467-469 ◽  
pp. 192-196
Author(s):  
Qun Li Wu
Keyword(s):  
Economic Growth ◽  
Growth Rate ◽  
Public Goods ◽  
Policy Evaluation ◽  
Optimal Size ◽  
Empirical Methods ◽  
Economic Growth Rate ◽  
Development Stages ◽  
Fiscal Expenditure ◽  
Lower Size

In perspective of maximizing the economic growth rate, this article examines the optimal size of China’s fiscal expenditure with theoretical and empirical methods. Based on exploring the Congested Public Goods Model and the Pure Public Goods Model, we estimate that during the year of 1978-2006 the optimal size of China’s fiscal expenditure is about 20-25% of GDP. According to this criterion, China's fiscal spending policies can be divided into three development stages: (1) the higher size phase (1978-1992); (2) the lower size phase (1993-2000); (3) the optimal size phase (2001-2006)

Influence of food availability, predation risk and initial body size on growth and maturation of Cloeon dipterum (Ephemeroptera: Baetidae)

Zoosymposia ◽  
2016 ◽  
Vol 11 ◽  
pp. 53-64 ◽  
Author(s):  
JAN ŠUPINA ◽  
JINDŘIŠKA BOJKOVÁ ◽  
DAVID S. BOUKAL
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Body Size ◽  
Predation Risk ◽  
Food Availability ◽  
Larval Mortality ◽  
Food Limitation ◽  
Larval Growth ◽  
Influence Of Food ◽  
Cloeon Dipterum

Larval growth and maturation in aquatic insects are phenotypically plastic and can change in response to the amount and quality of resources, or under predation risk. While better food conditions typically lead to faster growth and earlier maturation at larger body size and hence higher fecundity, the effects of predation risk can vary depending on its strength and selectivity with respect to size or stage. Studies on lotic mayflies (Ephemeroptera) have reported two direct and two indirect life history responses to increased predation risk: slower growth rate and later maturation at the same or smaller size, and faster or unaltered growth rate and earlier maturation at smaller body size. However, life history responses of standing water mayflies to predation risk are unknown. To fill this gap, we carried out a full-factorial laboratory experiment to study the influence of food availability (full/reduced) and predation risk (present/absent predator cues) by dragonfly larvae on growth and maturation of larvae of the lentic mayfly Cloeon dipterum. Males and females responded similarly to food limitation and predation risk. Predation risk had no effect on maturation size, larval mortality and metamorphic failure. However, growth rate, number of moults and development time were all affected by predation risk, and its net effect was modified by food availability and initial body size of the larvae. These results suggest that life history responses to suboptimal conditions depend on body size at the onset of such conditions. Finally, a small group of larvae grew at much slower rates and developed much longer than other individuals of similar initial size, possibly due to bet-hedging or inclusion of multiple genotypes in the experiment.

scholarly journals Identifying reliable fitness proxies for growing animals responding to anthropogenic changes

2020 ◽  
Author(s):  
Andrew D. Higginson
Keyword(s):  
Growth Rate ◽  
Mortality Rate ◽  
Predation Risk ◽  
Energy Use ◽  
Metabolic Costs ◽  
Theoretical Predictions ◽  
Increasing Temperature ◽  
The Impact ◽  
The Relationship ◽  
Increase Mortality Rate

ABSTRACTAnthropogenic influences on habitats often affect predation on species by introducing novel predators, supporting additional predators, or reducing animals’ ability to detect or avoid predators. Other changes may reduce the ability of animals to feed, or alter their energy use. An increase in predation risk is assumed to reduce prey populations by increasing mortality, reducing foraging and growth. Often animals don’t appear to have been adversely affected, or may even increase growth rate. However, theoretical predictions that may have been overlooked suggest that optimal foraging rate, mortality rate and growth rate may change in counter-intuitive ways, depending on exactly how predation risk or costs have been increased. Increasing predator density may increase mortality rate when foraging, reduce the safety of refuges, or alter the relationship between vigilance and attack likelihood. Increasing temperature may increase metabolic costs in ectotherms and reduce thermogenesis costs in endotherms, which affects the costs of active foraging and inactivity differently. Here, I review the theory on how predation risk and metabolic costs should affect foraging behaviour, mortality and growth in order to explain the great variation in behavioural responses. I show that in some situations animals may not respond behaviourally even though a change severely affects survival, and the mortality may be a poor metric of the impact of a change on population viability. In other situations a fitness proxy may change dramatically whilst fitness is unaffected due to compensatory changes in behaviour or life history. Other measures may change in a positive way whilst fitness declines. I describe how to identify the situations in the field and thereby make reliable measure of fitness in particular study systems. Overall, this work shows how behavioural theory can help understand the impacts of environmental change and highlights promising directions to better understand and mitigate their effects on ecosystems.

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