...Connor F. White; George V. Lauder ABSTRACT Fish swimming has classically been modeled as a rearwardly propagating wave of increasing amplitude and fixed frequency, based on kinematic data from large numbers of species in captivity. However, recent work on sharks swimming in natural environments has...

... function. Few species can survive prolonged periods of hypoxia and anoxia at tropical temperatures and those that do may rely on mitochondria plasticity in response to disruptions to oxygen availability. Two carpet sharks, the epaulette shark ( Hemiscyllium ocellatum ) and the grey carpet shark...

...Jason R. Treberg; Ben Speers-Roesch ABSTRACT The deep sea is the largest ecosystem on Earth but organisms living there must contend with high pressure, low temperature, darkness and scarce food. Chondrichthyan fishes (sharks and their relatives) are important consumers in most marine ecosystems...

... interests. © 2014. Published by The Company of Biologists Ltd 2014 Acoustic telemetry Energetics Hypoxia Logger Penguin Scaling Seal Shark Stroke frequency Temperature The collective term ‘biologging’ has been coined to describe a process by which researchers gain information...

...,tapetum structure and variations in optical performance with ontogenetic growth in two elasmobranch species: the carcharhinid sandbar shark,Carcharhinus plumbeus, inhabiting nearshore coastal waters, and the squalid shortspine spurdog, Squalus mitsukurii, inhabiting deeper waters of the continental shelf...

... to determine whether these post-prandial alkaline tide events were linked to secretion of H + (accompanied by Cl – ) in the stomach. Sharks were fitted with indwelling stomach tubes for pretreatment with omeprazole (five doses of 5 mg omeprazole per kilogram over 48 h) or comparable volumes of vehicle (saline...

... control in specialized suction feeding fishes. The hydrodynamics of suction feeding in white-spotted bamboo sharks ( Chiloscyllium plagiosum ) was studied in three behaviours: successful strikes, intraoral transports of prey and unsuccessful strikes. The area of the fluid velocity region around the head...

...-spotted bamboo sharks, Chiloscyllium plagiosum and compared it with that in teleosts. The internal movement of cranial elements and pressure in the buccal, hyoid and pharyngeal cavities that are directly responsible for suction generation was quantified using sonomicrometry and pressure transducers...

... secondary neurons that adjust the principal neurons'sensitivity to afferent inputs. Sharks were immobilized by cooling to 8–10°C. Following decapitation, at the level of the first gill, the cartilaginous skull containing the brain was removed and immersed in a 7–10°C shark Ringer solution. As shown...

... from the teleost pattern. * Author for correspondence (e-mail: [email protected] ) 29 1 2007 © The Company of Biologists Limited 2007 2007 gastric acid secretion chyme composition alkaline tide urea osmolality dogfish shark The feeding ecology of marine sharks...

... chloride secretion O 2 consumption CO 2 excretion gas exchange ratio pHi pHe acidosis alkalosis shark acetazolamide The rectal gland is a small finger-shaped organ in the posterior intestine of elasmobranchs. Its ionoregulatory and volume-regulatory functions were first characterized...

... metabolic pathways in several tissues of the dogfish shark, Squalus acanthias, after starvation and at 6, 20, 30 and 48 h post-feeding. We found a rapid and sustained ten-fold decrease in plasma β-hydroxybutyrate at 6 h and beyond compared with starved dogfish, suggesting an upregulation in the use...

...Cindy A. Duong; Chugey A. Sepulveda; Jeffrey B. Graham; Kathryn A. Dickson SUMMARY Mitochondrial proton leak was assessed as a potential heat source in the slow, oxidative (red) locomotor muscle and liver of the shortfin mako shark( Isurus oxyrinchus ), a regional endotherm that maintains...

...Chris M. Wood; Makiko Kajimura; Thomas P. Mommsen; Patrick J. Walsh SUMMARY We investigated the consequences of feeding for acid–base balance,nitrogen excretion, blood metabolites and osmoregulation in the Pacific spiny dogfish. Sharks that had been starved for 7 days were surgically fitted...

...Susan K. Fellner; Laurel Parker SUMMARY In vascular smooth muscle (VSM) of Squalus acanthias , endothelin-1(ET-1) signals via the ET B receptor. In both shark and mammalian VSM, ET-1 induces a rise in cytosolic Ca 2+ concentration([Ca 2+ ] i ) via activation of the inositol trisphosphate (IP 3...

...Nathan S. Hart; Thomas J. Lisney; N. Justin Marshall; Shaun P. Collin SUMMARY Elasmobranchs (sharks, skates and rays) are the modern descendents of the first jawed vertebrates and, as apex predators, often occupy the highest trophic levels of aquatic (predominantly marine) ecosystems. However...

...D. Bernal; D. Smith; G. Lopez; D. Weitz; T. Grimminger; K. Dickson; J. B. Graham SUMMARY Metabolic enzyme activities in red (RM) and white (WM) myotomal muscle and in the heart ventricle (HV) were compared in two lamnid sharks (shortfin mako and salmon shark), the common thresher shark and several...

... s –1 ) in the leopard shark Triakis semifasciata . Analysis of lateral displacement along the body indicates that the leopard shark is a subcarangiform swimmer. Longitudinal variation in red muscle strain was observed with strain amplitudes ranging from ±3.9% in the anterior,±6.6% in the mid...

...C. D. Wilga; G. V. Lauder SUMMARY The function of the heterocercal tail in sharks has long been debated in the literature. Previous kinematic data have supported the classical theory which proposes that the beating of the heterocercal caudal fin during steady horizontal locomotion pushes...

...Diego Bernal; Chugey Sepulveda; Jeffrey B. Graham SUMMARY The mako shark ( Isurus oxyrinchus ) has specialized vascular networks (retia mirabilia) forming counter-current heat exchangers that allow metabolic heat retention in certain regions of the body, including the aerobic, locomotor red muscle...