Predator-prey body size relationships of cod in a low-diversity marine system

Our knowledge of early evolution of snakes is improving, but all that we can infer about the evolution of modern clades of snakes such as boas (Booidea) is still based on isolated bones. Here, we resolve the phylogenetic relationships of Eoconstrictor fischeri comb. nov. and other booids from the early-middle Eocene of Messel (Germany), the best-known fossil snake assemblage yet discovered. Our combined analyses demonstrate an affinity of Eoconstrictor with Neotropical boas, thus entailing a South America-to-Europe dispersal event. Other booid species from Messel are related to different New World clades, reinforcing the cosmopolitan nature of the Messel booid fauna. Our analyses indicate that Eoconstrictor was a terrestrial, medium- to large-bodied snake that bore labial pit organs in the upper jaw, the earliest evidence that the visual system in snakes incorporated the infrared spectrum. Evaluation of the known palaeobiology of Eoconstrictor provides no evidence that pit organs played a role in the predator–prey relations of this stem boid. At the same time, the morphological diversity of Messel booids reflects the occupation of several terrestrial macrohabitats, and even in the earliest booid community the relation between pit organs and body size is similar to that seen in booids today.

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Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.2103 ◽

2014 ◽

Vol 281 (1797) ◽

pp. 20142103 ◽

Cited By ~ 29

Author(s):

Marlee A. Tucker ◽

Tracey L. Rogers

Keyword(s):

Community Structure ◽

Body Size ◽

Body Mass ◽

Marine Environment ◽

Trophic Level ◽

Marine Mammals ◽

Trophic Position ◽

Trophic Levels ◽

Predator Prey ◽

Terrestrial Mammals

Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial ( n = 51) and marine ( n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities.

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Predator-prey body size relationship in temporary wetlands: effect of predatory insects on prey size spectra and survival

Annales de Limnologie - International Journal of Limnology ◽

10.1051/limn/2016011 ◽

2016 ◽

Vol 52 ◽

pp. 205-216 ◽

Cited By ~ 2

Author(s):

Fabián Gastón Jara

Keyword(s):

Body Size ◽

Prey Size ◽

Temporary Wetlands ◽

Size Spectra ◽

Predator Prey ◽

Size Relationship ◽

Predatory Insects

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Is the scaling of swim speed in sharks driven by metabolism?

Biology Letters ◽

10.1098/rsbl.2015.0781 ◽

2015 ◽

Vol 11 (12) ◽

pp. 20150781 ◽

Cited By ~ 5

Author(s):

David M. P. Jacoby ◽

Penthai Siriwat ◽

Robin Freeman ◽

Chris Carbone

Keyword(s):

Body Size ◽

Ecosystem Functioning ◽

Foraging Ecology ◽

Geometric Model ◽

Predator Prey ◽

Marine Systems ◽

Movement Rates ◽

Scaling Relationship ◽

Model Predictions ◽

Ecological Parameters

The movement rates of sharks are intrinsically linked to foraging ecology, predator–prey dynamics and wider ecosystem functioning in marine systems. During ram ventilation, however, shark movement rates are linked not only to ecological parameters, but also to physiology, as minimum speeds are required to provide sufficient water flow across the gills to maintain metabolism. We develop a geometric model predicting a positive scaling relationship between swim speeds in relation to body size and ultimately shark metabolism, taking into account estimates for the scaling of gill dimensions. Empirical data from 64 studies (26 species) were compiled to test our model while controlling for the influence of phylogenetic similarity between related species. Our model predictions were found to closely resemble the observed relationships from tracked sharks, providing a means to infer mobility in particularly intractable species.

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Predator–prey mass ratio revisited: does preference of relative prey body size depend on individual predator size?

Functional Ecology ◽

10.1111/1365-2435.12680 ◽

2016 ◽

Vol 30 (12) ◽

pp. 1979-1987 ◽

Cited By ~ 16

Author(s):

Cheng‐Han Tsai ◽

Chih‐hao Hsieh ◽

Takefumi Nakazawa

Keyword(s):

Body Size ◽

Mass Ratio ◽

Predator Prey ◽

Predator Size ◽

Prey Mass

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Size-dependent functional response of Xenopus laevis on mosquito larvae

10.7287/peerj.preprints.26575 ◽

2018 ◽

Author(s):

Corey J Thorp ◽

Mhairi E Alexander ◽

James R Vonesh ◽

John Measey

Keyword(s):

Body Size ◽

Xenopus Laevis ◽

Functional Response ◽

Handling Time ◽

Mosquito Larvae ◽

Agricultural Pests ◽

Food Web Structure ◽

Predator Prey ◽

Predator Attack ◽

Considerable Individual Variation

Predators can play an important role in regulating prey abundance and diversity, determining food web structure and function, and contributing to important ecosystem services, including the regulation of agricultural pests and disease vectors. Thus, the ability to predict predator impact on prey is an important goal in ecology. Often predators of the same species are assumed to be functionally equivalent, despite considerable individual variation in predator traits known to be important for shaping predator-prey interactions, like body size. This assumption may greatly oversimplify our understanding of within species functional diversity and undermine our ability to predict predator effects on prey. Here we examine the degree to which predator-prey interactions are functionally homogenous across a natural range of predator body size. Specifically, we quantify the size-dependence of the functional response of African clawed frogs (Xenopus laevis) preying on mosquito larvae (Culex pipiens). Three size classes of predators, small (15-30mm snout-vent length), medium (50-60mm) and large (105-120mm), were presented with five densities of prey to determine functional response type and to estimate search efficiency and handling time parameters generated from the models. The results of mesocosm experiments show that functional response of X. laevis changed with size: small predators exhibited a Type II response, while medium and large predators exhibited Type III responses. Both functional response and behavioural data showed an inversely proportional relationship between predator attack rate and predator size. Small and medium predators had highest and lowest handling time respectively. That the functional response changed with the size of predator suggests that predators with overlapping cohorts may have a dynamic impact on prey populations. Therefore, predicting the functional response of a single size-matched predator in an experiment may be a misrepresentation of the predator’s potential impact on a prey population.

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Study on evolution of a predator–prey model in a polluted environment

Nonlinear Analysis Modelling and Control ◽

10.15388/namc.2021.26.24148 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1052-1070

Author(s):

Bing Liu ◽

Xin Wang ◽

Le Song ◽

Jingna Liu

Keyword(s):

Body Size ◽

Function Analysis ◽

Fitness Function ◽

Rapid Evolution ◽

Evolutionary Model ◽

The Body ◽

Predator Prey ◽

Predator Prey Model ◽

Prey Model

In this paper, we investigate the effects of pollution on the body size of prey about a predator–prey evolutionary model with a continuous phenotypic trait in a pulsed pollution discharge environment. Firstly, an eco-evolutionary predator–prey model incorporating the rapid evolution is formulated to investigate the effects of rapid evolution on the population density and the body size of prey by applying the quantitative trait evolutionary theory. The results show that rapid evolution can increase the density of prey and avoid population extinction, and with the worsening of pollution, the evolutionary traits becomes smaller gradually. Next, by employing the adaptive dynamic theory, a long-term evolutionary model is formulated to evaluate the effects of long-term evolution on the population dynamics and the effects of pollution on the body size of prey. The invasion fitness function is given, which reflects whether the mutant can invade successfully or not. Considering the trade-off between the intrinsic growth rate and the evolutionary trait, the critical function analysis method is used to investigate the dynamics of such slow evolutionary system. The results of theoretical analysis and numerical simulations conclude that pollution affects the evolutionary traits and evolutionary dynamics. The worsening of the pollution leads to a smaller body size of prey due to natural selection, while the opposite is more likely to generate evolutionary branching.

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Influence of intra‐ and interspecific variation in predator–prey body size ratios on trophic interaction strengths

Ecology and Evolution ◽

10.1002/ece3.6332 ◽

2020 ◽

Vol 10 (12) ◽

pp. 5946-5962 ◽

Cited By ~ 1

Author(s):

Ross N. Cuthbert ◽

Ryan J. Wasserman ◽

Tatenda Dalu ◽

Horst Kaiser ◽

Olaf L. F. Weyl ◽

...

Keyword(s):

Body Size ◽

Interspecific Variation ◽

Trophic Interaction ◽

Predator Prey

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Life History Processes, Ontogenetic Development, and Density Dependence

Population and Community Ecology of Ontogenetic Development ◽

10.23943/princeton/9780691137575.003.0002 ◽

2013 ◽

Author(s):

André M. de Roos ◽

Lennart Persson

Keyword(s):

Body Size ◽

Theoretical Basis ◽

Population Level ◽

Growth Patterns ◽

Ontogenetic Development ◽

Chain Model ◽

Predator Prey ◽

Predator Prey Model ◽

Classical Models ◽

Food Chain Model

This chapter first considers the question of how ecologists have conceptualized populations. In other words, how has their research looked at “group[s] of individuals of one species”? It reflects on the classical models that form the theoretical basis of population ecology: the Lotka–Volterra competition model, Lotka–Volterra predator–prey model, and Fretwell–Oksanen food chain model. It then argues that much of ecologists' understanding about populations and communities and their dynamics is couched in terms of mathematical models. The remainder of the chapter discusses individual- versus population-level assumptions, the population dynamical triad, growth patterns and ecology of ontogenetic development, body-size scaling and magnitude of body-size changes, and changes in ecological roles over ontogeny.

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