Fovea-Like Photoreceptor Specialisations Underlie Single UV-Cone Driven Prey Capture Behaviour in Zebrafish

Biodiversity and ecosystem function are often correlated, but there are multiple hypotheses about the mechanisms underlying this relationship. Ecosystem functions such as primary or secondary production may be maximized by species richness, evenness in species abundances, or the presence or dominance of species with certain traits. Here, we combined surveys of natural fish communities (conducted in July and August, 2016) with morphological trait data to examine relationships between diversity and ecosystem function (quantified as fish community biomass) across 14 subtidal eelgrass meadows in the Northeast Pacific (54° N 130° W). We employed both taxonomic and functional trait measures of diversity to investigate if ecosystem function is driven by species diversity (complementarity hypothesis) or by the presence or dominance of species with particular trait values (selection or dominance hypotheses). After controlling for environmental variation, we found that fish community biomass is maximized when taxonomic richness and functional evenness is low, and in communities dominated by species with particular trait values – those associated with benthic habitats and prey capture. While previous work on fish communities has found that species richness is positively correlated with ecosystem function, our results instead highlight the capacity for regionally prevalent and locally dominant species to drive ecosystem function in moderately diverse communities. We discuss these alternate links between community composition and ecosystem function and consider their divergent implications for ecosystem valuation and conservation prioritization.

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Faculty Opinions recommendation of Speciation through the lens of biomechanics: locomotion, prey capture and reproductive isolation.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726740275.793536935 ◽

2017 ◽

Author(s):

Oswald Schmitz

Keyword(s):

Reproductive Isolation ◽

Prey Capture

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Does Prey Capture Induce Area-Restricted Search? A Fine-Scale Study Using GPS in a Marine Predator, the Wandering Albatross

The American Naturalist ◽

10.2307/4541144 ◽

2007 ◽

Vol 170 (5) ◽

pp. 734 ◽

Cited By ~ 2

Author(s):

Weimerskirch ◽

Pinaud ◽

Frédéric Pawlowski ◽

Bost

Keyword(s):

Prey Capture ◽

Fine Scale ◽

Marine Predator ◽

Wandering Albatross

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Extensive Variation in the Activities of Pseudocerastes and Eristicophis Viper Venoms Suggests Divergent Envenoming Strategies Are Used for Prey Capture

Toxins ◽

10.3390/toxins13020112 ◽

2021 ◽

Vol 13 (2) ◽

pp. 112

Author(s):

Bianca op den Brouw ◽

Francisco C. P. Coimbra ◽

Lachlan A. Bourke ◽

Tam Minh Huynh ◽

Danielle H. W. Vlecken ◽

...

Keyword(s):

Prey Capture ◽

Anticoagulant Activity ◽

Protein Composition ◽

Coagulation Factors ◽

Arid Environments ◽

Factor X ◽

Venom Protein ◽

Research Attention ◽

Future Assessment ◽

Viper Venoms

Snakes of the genera Pseudocerastes and Eristicophis (Viperidae: Viperinae) are known as the desert vipers due to their association with the arid environments of the Middle East. These species have received limited research attention and little is known about their venom or ecology. In this study, a comprehensive analysis of desert viper venoms was conducted by visualising the venom proteomes via gel electrophoresis and assessing the crude venoms for their cytotoxic, haemotoxic, and neurotoxic properties. Plasmas sourced from human, toad, and chicken were used as models to assess possible prey-linked venom activity. The venoms demonstrated substantial divergence in composition and bioactivity across all experiments. Pseudocerastes urarachnoides venom activated human coagulation factors X and prothrombin and demonstrated potent procoagulant activity in human, toad, and chicken plasmas, in stark contrast to the potent neurotoxic venom of P. fieldi. The venom of E. macmahonii also induced coagulation, though this did not appear to be via the activation of factor X or prothrombin. The coagulant properties of P. fieldi and P. persicus venoms varied among plasmas, demonstrating strong anticoagulant activity in the amphibian and human plasmas but no significant effect in that of bird. This is conjectured to reflect prey-specific toxin activity, though further ecological studies are required to confirm any dietary associations. This study reinforces the notion that phylogenetic relatedness of snakes cannot readily predict venom protein composition or function. The significant venom variation between these species raises serious concerns regarding antivenom paraspecificity. Future assessment of antivenom is crucial.

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Antlion allometry suggests a greater importance of prey capture among first larval instars

Ethology Ecology & Evolution ◽

10.1080/03949370.2021.1893825 ◽

2021 ◽

pp. 1-8

Author(s):

Alejandro G. Farji-Brener ◽

Agostina S. Juncosa-Polzella ◽

Daniela Madrigal-Tejada ◽

Diego Centeno-Alvarado ◽

Mariana Hernández-Soto ◽

...

Keyword(s):

Prey Capture ◽

Larval Instars

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Prey Capturing Dynamics and Nanomechanically Graded Cutting Apparatus of Dragonfly Nymph

Materials ◽

10.3390/ma14030559 ◽

2021 ◽

Vol 14 (3) ◽

pp. 559

Author(s):

Lakshminath Kundanati ◽

Prashant Das ◽

Nicola M. Pugno

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

High Speed ◽

Prey Capture ◽

High Speed Photography ◽

Sensory Organs ◽

Dragonfly Nymph ◽

Drag Forces ◽

Predatory Insects ◽

Dragonfly Nymphs

Aquatic predatory insects, like the nymphs of a dragonfly, use rapid movements to catch their prey and it presents challenges in terms of movements due to drag forces. Dragonfly nymphs are known to be voracious predators with structures and movements that are yet to be fully understood. Thus, we examine two main mouthparts of the dragonfly nymph (Libellulidae: Insecta: Odonata) that are used in prey capturing and cutting the prey. To observe and analyze the preying mechanism under water, we used high-speed photography and, electron microscopy. The morphological details suggest that the prey-capturing labium is a complex grasping mechanism with additional sensory organs that serve some functionality. The time taken for the protraction and retraction of labium during prey capture was estimated to be 187 ± 54 ms, suggesting that these nymphs have a rapid prey mechanism. The Young’s modulus and hardness of the mandibles were estimated to be 9.1 ± 1.9 GPa and 0.85 ± 0.13 GPa, respectively. Such mechanical properties of the mandibles make them hard tools that can cut into the exoskeleton of the prey and also resistant to wear. Thus, studying such mechanisms with their sensory capabilities provides a unique opportunity to design and develop bioinspired underwater deployable mechanisms.

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A numerical study of fish adaption behaviors in complex environments with a deep reinforcement learning and immersed boundary–lattice Boltzmann method

Scientific Reports ◽

10.1038/s41598-021-81124-8 ◽

2021 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Yi Zhu ◽

Fang-Bao Tian ◽

John Young ◽

James C. Liao ◽

Joseph C. S. Lai

Keyword(s):

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Prey Capture ◽

Numerical Study ◽

Benchmark Problems ◽

Immersed Boundary ◽

Complex Environments ◽

Fish Model ◽

Point To Point ◽

Boltzmann Method

AbstractFish adaption behaviors in complex environments are of great importance in improving the performance of underwater vehicles. This work presents a numerical study of the adaption behaviors of self-propelled fish in complex environments by developing a numerical framework of deep learning and immersed boundary–lattice Boltzmann method (IB–LBM). In this framework, the fish swimming in a viscous incompressible flow is simulated with an IB–LBM which is validated by conducting two benchmark problems including a uniform flow over a stationary cylinder and a self-propelled anguilliform swimming in a quiescent flow. Furthermore, a deep recurrent Q-network (DRQN) is incorporated with the IB–LBM to train the fish model to adapt its motion to optimally achieve a specific task, such as prey capture, rheotaxis and Kármán gaiting. Compared to existing learning models for fish, this work incorporates the fish position, velocity and acceleration into the state space in the DRQN; and it considers the amplitude and frequency action spaces as well as the historical effects. This framework makes use of the high computational efficiency of the IB–LBM which is of crucial importance for the effective coupling with learning algorithms. Applications of the proposed numerical framework in point-to-point swimming in quiescent flow and position holding both in a uniform stream and a Kármán vortex street demonstrate the strategies used to adapt to different situations.

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Whole body withdrawal circuit and its involvement in the behavioral hierarchy of the mollusk Clione limacina

Journal of Neurophysiology ◽

10.1152/jn.1996.75.2.529 ◽

1996 ◽

Vol 75 (2) ◽

pp. 529-537 ◽

Cited By ~ 17

Author(s):

T. P. Norekian ◽

R. A. Satterlie

Keyword(s):

Feeding Behavior ◽

Motor Neurons ◽

Prey Capture ◽

The Body ◽

Whole Body ◽

High Threshold ◽

Behavioral Repertoire ◽

Withdrawal Behavior ◽

Cerebral Neurons ◽

Clione Limacina

1. The behavioral repertoire of the holoplanktonic pteropod mollusk Clione limacina includes a few well-defined behaviors organized in a priority sequence. Whole body withdrawal takes precedence over slow swimming behavior, whereas feeding behavior is dominant over withdrawal. In this study a group of neurons is described in the pleural ganglia, which controls whole body withdrawal behavior in Clione. Each pleural withdrawal (Pl-W) neuron has a high threshold for spike generation and is capable of inducing whole body withdrawal in a semi-intact preparation: retraction of the body-tail, wings, and head. Each Pl-W neuron projects axons into the main central nerves and innervates all major regions of the body. 2. Stimulation of Pl-W neurons produces inhibitory inputs to swim motor neurons that terminate swimming activity in the preparation. In turn, Pl-W neurons receive inhibitory inputs from the cerebral neurons involved in the control of feeding behavior in Clione, neurons underlying extrusion of specialized prey capture appendages. Thus it appears that specific inhibitory connections between motor centers can explain the dominance of withdrawal behavior over slow swimming and feeding over withdrawal in Clione.

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