685 results match your criteria swim fin

The relative effects of pace of life-history and habitat characteristics on the evolution of sexual ornaments: A comparative assessment.

Evolution 2021 Sep 21. Epub 2021 Sep 21.

Department of Zoology, Stockholm University, Stockholm, 114 18, Sweden.

Selection may favor greater investment into sexual ornaments when opportunities for future reproduction are limited, e.g. under high adult mortality. Read More

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September 2021

No evidence for conspecific recruitment for cooperative hunting in lionfish .

R Soc Open Sci 2021 Sep 15;8(9):210828. Epub 2021 Sep 15.

Institution of Biology, University of Neuchatel, Emile-Argand 11, Neuchatel 2000, Switzerland.

Lionfish are common piscivores in the Indo-Pacific and invasive in the Caribbean. A fin flaring pattern, involving a rapid undulation of the caudal fin and sequential turning of both pectoral fins, was described in zebra lionfish as a signal to initiate cooperative hunting, and it was hypothesized that such hunting tactics may also exist in other lionfish species and contribute to their successful invasion in the Caribbean. Here, we investigated one of those invasive species, , in its natural range in the Red Sea. Read More

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September 2021

Increasing Viscosity Helps Explain Locomotor Control in Swimming .

K Lutek E M Standen

Integr Org Biol 2021 10;3(1):obab024. Epub 2021 Aug 10.

Department of Biology, University of Ottawa, 30 Marie-Curie Private, Ottawa, ON K1N 6N5, Canada.

Locomotion relies on the successful integration of sensory information to adjust brain commands and basic motor rhythms created by central pattern generators. It is not clearly understood how altering the sensory environment impacts control of locomotion. In an aquatic environment, mechanical sensory feedback to the animal can be readily altered by adjusting water viscosity. Read More

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An Updated Narrative Review on Ergometric Systems Applied to Date in Assessing Divers' Fitness.

Healthcare (Basel) 2021 Aug 13;9(8). Epub 2021 Aug 13.

Forschungsgruppe Experimentelle Chirurgie, Universitäts-Klinikum Düsseldorf, Moorenstrasse 5, 40225 Düsseldorf, Germany.

Many recreational divers suffer medical conditions, potentially jeopardizing their safety. To scale down risks, medical examinations are mandatory and overwhelmingly performed using bicycle ergometry, which overlooks some important aspects of diving. Searching ergometric systems that better address the underwater environment, a systematic literature search was conducted using the keywords 'diving', 'fitness', 'ergometry', and 'exertion'. Read More

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Functions of the Thyroid-Stimulating Hormone on Key Developmental Features Revealed in a Series of Zebrafish Dyshormonogenesis Models.

Cells 2021 Aug 4;10(8). Epub 2021 Aug 4.

State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.

The hypothalamic-pituitary-thyroid (HPT) axis regulates many critical features in vertebrates. Utilizing TALENs and CRISPR/Cas9 techniques, thyroid-stimulating hormone subunit beta a (), thyroglobulin (), and solute carrier family 16 member 2 () mutant zebrafish lines were generated. Among the three mutants, the earliest time point for the significantly altered T3 contents was observed in mutants, which resulted in the most severe defects, including typical defects such as the retardation of inflated anterior swimming bladder (aSB), proper formation of fin ray and posterior squamation (SP), the larval-to-juvenile transition (LTJT) process, juvenile growth retardation, and mating failure. Read More

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Archerfish coordinate fin maneuvers with their shots.

J Exp Biol 2021 04 26;224(8). Epub 2021 Apr 26.

Department of Animal Physiology, University of Bayreuth, 95440 Bayreuth, Germany.

Archerfish down a variety of aerial prey from a range of distances using water jets that they adjust to the size and distance of their prey. We describe here that characteristic rapid fin maneuvers, most notably of the pectoral and pelvic fins, are precisely coordinated with the release of the jet. We discovered these maneuvers in two fish, the jets of which had been characterized in detail, that had been trained to shoot from fixed positions at targets at different heights and that remained stable during their shots. Read More

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Oxygen-enriched Air Decreases Ventilation during High-intensity Fin-swimming Underwater.

Int J Sports Med 2021 Aug 16. Epub 2021 Aug 16.

Research Group Experimenal Surgery, University Hospital Düsseldorf, Dusseldorf, Germany.

Oxygen-enriched air is commonly used in the sport of SCUBA-diving and might affect ventilation and heart rate, but little work exists for applied diving settings. We hypothesized that ventilation is decreased especially during strenuous underwater fin-swimming when using oxygen-enriched air as breathing gas. Ten physically-fit divers (age: 25±4; 5 females; 67±113 open-water dives) performed incremental underwater fin-swimming until exhaustion at 4 m water depth with either normal air or oxygen-enriched air (40% O) in a double-blind, randomized within-subject design. Read More

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How fish traits and functional diversity respond to environmental changes and species invasion in the largest river in Southeastern China.

PeerJ 2021 23;9:e11824. Epub 2021 Jul 23.

Key Laboratory of Mariculture (Ocean University of China), Ministry of Education, Qingdao, Shandong, China.

Background: Freshwater fish populations are facing multiple stressors, including climate change, species invasion, and anthropogenic interference. Temporal studies of fish functional diversity and community assembly rules based on trait-environment relationships provide insights into fish community structure in riverine ecosystems.

Methods: Fish samples were collected in 2015 in the Min River, the largest freshwater riverine system in Southeastern China. Read More

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Form, function, and divergence of a generic fin shape in small cetaceans.

PLoS One 2021 11;16(8):e0255464. Epub 2021 Aug 11.

Institute for Terrestrial and Aquatic Wildlife Research, The University of Veterinary Medicine Hannover, Foundation, Buesum, Germany.

Tail flukes as well as the dorsal fin are the apomorphic traits of cetaceans which appeared during the evolutionary process of adaptation to the aquatic life. Both appendages present a wing-like shape associated with lift generation and low drag. We hypothesized that the evolution of fins as lifting structures led to a generic wing design, where the dimensionless parameters of the fin cross-sections are invariant with respect to the body length and taxonomy of small cetaceans (Hypothesis I). Read More

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Fish can save energy via proprioceptive sensing.

Bioinspir Biomim 2021 08 16;16(5). Epub 2021 Aug 16.

State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871, People's Republic of China.

Fish have evolved diverse and robust locomotive strategies to swim efficiently in complex fluid environments. However, we know little, if anything, about how these strategies can be achieved. Although most studies suggest that fish rely on the lateral line system to sense local flow and optimise body undulation, recent work has shown that fish are still able to gain benefits from the local flow even with the lateral line impaired. Read More

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Maneuverable gait selection for a novel fish-inspired robot using a CMA-ES-assisted workflow.

Bioinspir Biomim 2021 08 27;16(5). Epub 2021 Aug 27.

The Polytechnic School, Ira A Fulton Schools of Engineering, Arizona State University, Mesa, AZ, 85212, United States of America.

Among underwater vehicles, fish-inspired designs are often selected for their efficient gaits; these designs, however, remain limited in their maneuverability, especially in confined spaces. This paper presents a new design for a fish-inspired robot with two degree-of-freedom pectoral fins and a single degree-of-freedom caudal fin. This robot has been designed to operate in open-channel canals in the presence of external disturbances. Read More

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Acoustic tracking of fin whales: Habitat use and movement patterns within a Canadian Pacific fjord system.

J Acoust Soc Am 2021 06;149(6):4264

Gitga'at Oceans and Lands Department, 445 Hayimiisaxaa Way, Hartley Bay, British Columbia V0V 1A0, Canada.

Fin whale 20 Hz calls were detected, localized, and tracked using a 10 km aperture network of three acoustic receivers deployed for 11 months in a Pacific Canadian fjord system. The area has been historically important for fin whales and is located along a route that tankers will begin using in 2024. A total of 6712 calls were localized, and trajectories were fitted for 55 acoustic tracks. Read More

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Design and experimental evaluation of the novel undulatory propulsors for biomimetic underwater robots.

Bioinspir Biomim 2021 07 26;16(5). Epub 2021 Jul 26.

School of Electrical Engineering and Information, Southwest Petroleum University, No.8 Xindu Avenue, Chengdu, 610500, People's Republic of China.

Inspired by wide and elongated fins of aquatic species, robotic undulatory propulsors are developed to achieve advanced maneuverability. Through biological observation, undulatory fins are typically comprised of more than 100 fin rays to propagate continuous and diverse propulsive waves for agile locomotion. Due to practical engineering restrictions, most robotic undulatory propulsors are characterized by limit number of long fin rays which intersect flexible fin surfaces as backbones and partition them into multiple membrane-like segments. Read More

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Flexible tensegrity wing design and insights in principles of swimming kinematics of batoid rays.

Jun Chen

Bioinspir Biomim 2021 07 19;16(5). Epub 2021 Jul 19.

The Joint Laboratory of Ocean Observing and Detection, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, Shandong Province 266237, People's Republic of China.

A novel tensegrity wing design is first proposed which can emulate the kinematic waves of the pectoral fin of batoid rays and has a simple structure for manufacture. The attitude control and the regulation of wing natural frequency are realized by wing morphing. Then analytical insights in batoid ray swimming are gained by analyzing the analytical wing (cable)-fluid interaction model, whose parameters are determined based on the biological data. Read More

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Towards non-invasive heart rate monitoring in free-ranging cetaceans: a unipolar suction cup tag measured the heart rate of trained Risso's dolphins.

Philos Trans R Soc Lond B Biol Sci 2021 08 28;376(1831):20200225. Epub 2021 Jun 28.

Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba 277-8564, Japan.

Heart rate monitoring in free-ranging cetaceans to understand their behavioural ecology and diving physiology is challenging. Here, we developed a simple, non-invasive method to monitor the heart rate of cetaceans in the field using an electrocardiogram-measuring device and a single suction cup equipped with an electrode. The unipolar suction cup was placed on the left lateral body surface behind the pectoral fin of Risso's dolphins () and a false killer whale () in captivity; their heart rate was successfully monitored. Read More

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Carbofuran affects behavior and metabolism of the Atlantic Forest lambari Deuterodon iguape, a native species from Brazil.

Environ Sci Pollut Res Int 2021 Jun 25. Epub 2021 Jun 25.

Instituto de Pesca - Governo do Estado de São Paulo, Av. Professor Wladimir Besnard, s/n, Caixa Postal 157, Cananéia, SP, 11900-000, Brazil.

One of the major causes of aquatic biodiversity loss is the contamination of the environment by pesticides. Even though there is a considerable amount of studies on the subject, there are still few that deal with the effects of carbofuran on native species in Brazil. Although carbofuran is widely used in Brazil, its action on native organisms, such as the Atlantic Forest lambari Deuterodon iguape, has not yet been studied. Read More

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Scaling of oscillatory kinematics and Froude efficiency in baleen whales.

J Exp Biol 2021 07 9;224(13). Epub 2021 Jul 9.

Hopkins Marine Station, Stanford University, Pacific Grove, CA 93950, USA.

High efficiency lunate-tail swimming with high-aspect-ratio lifting surfaces has evolved in many vertebrate lineages, from fish to cetaceans. Baleen whales (Mysticeti) are the largest swimming animals that exhibit this locomotor strategy, and present an ideal study system to examine how morphology and the kinematics of swimming scale to the largest body sizes. We used data from whale-borne inertial sensors coupled with morphometric measurements from aerial drones to calculate the hydrodynamic performance of oscillatory swimming in six baleen whale species ranging in body length from 5 to 25 m (fin whale, Balaenoptera physalus; Bryde's whale, Balaenoptera edeni; sei whale, Balaenoptera borealis; Antarctic minke whale, Balaenoptera bonaerensis; humpback whale, Megaptera novaeangliae; and blue whale, Balaenoptera musculus). Read More

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Fin sweep angle does not determine flapping propulsive performance.

J R Soc Interface 2021 05 26;18(178):20210174. Epub 2021 May 26.

Faculty of Engineering and Physical Sciences, University of Southampton, Southampton Boldrewood Innovation Campus, UK.

The importance of the leading-edge sweep angle of propulsive surfaces used by unsteady swimming and flying animals has been an issue of debate for many years, spurring studies in biology, engineering, and robotics with mixed conclusions. In this work, we provide results from three-dimensional simulations on single-planform finite foils undergoing tail-like (pitch-heave) and flipper-like (twist-roll) kinematics for a range of sweep angles covering a substantial portion of animals while carefully controlling all other parameters. Our primary finding is the negligible 0. Read More

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Shape memory alloy-driven undulatory locomotion of a soft biomimetic ray robot.

Bioinspir Biomim 2021 Sep 9;16(6). Epub 2021 Sep 9.

Department of Mechanical Convergence Engineering, Gyeongsang National University, 54, 48-Bun-gil Charyong-ro, Uichang-gu, Changwon, Gyeongnam 51391, Republic of Korea.

The objective of this study was to imitate undulatory motion, which is a commonly observed swimming mechanism of rays, using a soft morphing actuator. To achieve the undulatory motion, an artificial muscle built with shape memory alloy-based soft actuators was exploited to control the shape-changing behavior of a soft fin membrane. Artificial undulating fins were divided into two categories according to the method of generating the wave motion: single and multiple actuator-driven fins. Read More

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September 2021

Fin-fin interactions during locomotion in a simplified biomimetic fish model.

Bioinspir Biomim 2021 09 8;16(4). Epub 2021 Sep 8.

The Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, United States of America.

Fish median fins are extremely diverse, but their function is not yet fully understood. Various biological studies on fish and engineering studies on flapping foils have revealed that there are hydrodynamic interactions between fins arranged in tandem and that these interactions can lead to improved performance by the posterior fin. This performance improvement is often driven by the augmentation of a leading-edge vortex on the trailing fin. Read More

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September 2021

Trout-like multifunctional piezoelectric robotic fish and energy harvester.

Bioinspir Biomim 2021 06 23;16(4). Epub 2021 Jun 23.

G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States of America.

This work presents our experimental studies on a trout-inspired multifunctional robotic fish as an underwater swimmer and energy harvester. Fiber-based flexible piezoelectric composites with interdigitated electrodes, specifically macro-fiber composite (MFC) structures, strike a balance between the deformation and actuation force capabilities to generate hydrodynamic propulsion without requiring additional mechanisms for motion amplification. A pair of MFC laminates bracketing a passive fin functions like artificial muscle when driven out of phase to expand and contract on each side to create bending. Read More

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The fast and the tendinous? Locomotor modifications of the caudal peduncle in Gila spp. from the American Southwest.

Zoology (Jena) 2021 06 26;146:125924. Epub 2021 Mar 26.

Department of Biological Sciences, 617 S. Beaver St., Flagstaff, AZ, 86011, United States.

In the American Southwest, the fishes within the genus Gila evolved in an environment with seasonal rainstorms that caused stochastic flooding. Some species within this genus, such as bonytail (Gila elegans), possess locomotor morphologies that are similar to those seen in high-performance swimmers such as tuna and lamnid sharks. These shared features include a shallow caudal peduncle, lunate tail, and mechanisms to transmit force from the anterior musculature to the tail fin. Read More

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Hydrodynamical effect of parallelly swimming fish using computational fluid dynamics method.

PLoS One 2021 3;16(5):e0250837. Epub 2021 May 3.

Graduate school of Agriculture, Kindai University, Nakamachi, Nara, Japan.

Fish form schools because of many possible reasons. However, the hydrodynamic mechanism whereby the energy efficiency of fish schools is improved still remains unclear. There are limited examples of fish models based on actual swimming movements using simulation, and the movements in existing models are simple. Read More

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Long lasting effects of early temperature exposure on the swimming performance and skeleton development of metamorphosing Gilthead seabream (Sparus aurata L.) larvae.

Sci Rep 2021 Apr 22;11(1):8787. Epub 2021 Apr 22.

Biology Department, University of Crete, Vasilika Vouton, 70013, Heraklion, Crete, Greece.

Temperatures experienced during early ontogeny significantly influence fish phenotypes, with clear consequences for the wild and reared stocks. We examined the effect of temperature (17, 20, or 23 °C) during the short embryonic and yolk-sac larval period, on the swimming performance and skeleton of metamorphosing Gilthead seabream larvae. In the following ontogenetic period, all fish were subjected to common temperature (20 °C). Read More

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Beyond the Kármán gait: knifefish swimming in periodic and irregular vortex streets.

J Exp Biol 2021 05 18;224(10). Epub 2021 May 18.

Department of Ecology, Evolution, and Organismal Biology, Kennesaw State University, Kennesaw, GA 30144, USA.

Neotropical freshwater fishes such as knifefishes are commonly faced with navigating intense and highly unsteady streams. However, our knowledge on locomotion in apteronotids comes from laminar flows, where the ribbon fin dominates over the pectoral fins or body bending. Here, we studied the 3D kinematics and swimming control of seven black ghost knifefish (Apteronotus albifrons) moving in laminar flows (flow speed U∞≈1-5 BL s-1) and in periodic vortex streets (U∞≈2-4 BL s-1). Read More

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Archerfish coordinate fin maneuvers with their shots.

J Exp Biol 2021 04 26;224(8). Epub 2021 Apr 26.

Department of Animal Physiology, University of Bayreuth, 95440 Bayreuth, Germany.

Archerfish down a variety of aerial prey from a range of distances using water jets that they adjust to the size and distance of their prey. We describe here that characteristic rapid fin maneuvers, most notably of the pectoral and pelvic fins, are precisely coordinated with the release of the jet. We discovered these maneuvers in two fish, the jets of which had been characterized in detail, that had been trained to shoot from fixed positions at targets at different heights and that remained stable during their shots. Read More

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Outbreak of hirudiniasis in aquarium-reared albino red-bellied pacu Piaractus brachypomus.

Dis Aquat Organ 2021 Mar 11;144:55-59. Epub 2021 Mar 11.

ICAR-Central Island Agricultural Research Institute, Port Blair, Andaman and Nicobar Islands 744105, India.

We report hirudiniasis caused by the leech Hemiclepsis marginata asiatica Moore, 1924 in albino red-bellied pacu (pirapitinga) Piaractus brachypomus (Cuvier, 1818), constituting the first documentation of a freshwater fish species being affected in India. The outbreak occurred in a tank of an aquarium-fish retailer; infested fish appeared asphyxiated, unable to swim or swimming upside down, with cloudy eyes and body with thick mucus secretion. The prevalence and mortality was 100%, with a mean intensity of 81 leeches per fish. Read More

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Fish without Tail Fins-Exploring the Function of Tail Morphology of the First Vertebrates.

Integr Comp Biol 2021 Jul;61(1):37-49

Department of Natural History, Royal Ontario Museum, Toronto, ON M5S 2C6, Canada.

We use a series of hydrodynamic experiments on abstracted models to explore whether primitive vertebrates may have swum under various conditions without a clearly-differentiated tail fin. Cambrian vertebrates had post-anal stubby tails, some had single dorsal and ventral fins, but none had yet evolved a clearly differentiated caudal fin typical of post-Cambrian fishes, and must have relied on their long and flexible laterally-compressed bodies for locomotion, i.e. Read More

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Corrigendum: The effect of variable stiffness of tuna-like fish body and fin on swimming performance (2021 Bioinspir. Biomim. 16 016003).

Bioinspir Biomim 2021 Feb 23. Epub 2021 Feb 23.

Division of Ocean Science and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Shenzhen , 518055, CHINA.

We provide a corrigendum for the paper "The effect of variable stiffness of tuna-like fish body and fin on swimming performance" (2021 Bioinspir. Biomim. 16 016003). Read More

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February 2021

Effects of wave-driven water flow on the fast-start escape response of juvenile coral reef damselfishes.

J Exp Biol 2021 03 25;224(Pt 6). Epub 2021 Mar 25.

Division of Evolution, Ecology and Genetics, Research School of Biology, Australian National University, Canberra, ACT 0200, Australia

Fish often evade predators with a fast-start escape response. Studies typically examine this behaviour in still water despite water motion being an inherent feature of aquatic ecosystems. In shallow habitats, waves create complex flows that likely influence escape performance, particularly in small fishes with low absolute swimming speeds relative to environmental flows. Read More

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