Morphological and functional development of the spiral intestine in cloudy catshark (Scyliorhinus torazame) [RESEARCH ARTICLE]
Yuki Honda, Wataru Takagi, Marty K. S. Wong, Nobuhiro Ogawa, Kotaro Tokunaga, Kazuya Kofuji, and Susumu Hyodo Cartilaginous fish have a comparatively short intestine known as the spiral intestine that is comprised of a helical spiral of intestinal mucosa. However, morphological and functional development of the spiral intestine is not well described. Unlike teleosts, cartilaginous fish are characterized by an extremely long developmental period in ovo or in utero for example; in the oviparous cloudy catshark (Schyliorhinus torazame), the developing fish remains inside the egg capsule for up to six months, suggesting that t...
Source: Journal of Experimental Biology - June 11, 2020 Category: Biology Authors: Honda, Y., Takagi, W., Wong, M. K. S., Ogawa, N., Tokunaga, K., Kofuji, K., Hyodo, S. Tags: RESEARCH ARTICLE Source Type: research

Mitochondrial performance of a continually growing marine bivalve, Mytilus edulis Linnaeus, depends on the body size [RESEARCH ARTICLE]
Alexey Sukhotin, Anton Kovalev, Eugene Sokolov, and Inna M. Sokolova Allometric decline of mass-specific metabolic rate with increasing body size in organisms is a well-documented phenomenon. Despite a long history of research the mechanistic causes of metabolic scaling with body size remain under debate. Some hypotheses suggest that intrinsic factors such as allometry of cellular and mitochondrial metabolism may contribute to the organismal-level metabolic scaling. The aim of our present study was to determine the metabolic allometry at the mitochondrial level using a continually growing marine ectotherm, the mussel Mytil...
Source: Journal of Experimental Biology - June 11, 2020 Category: Biology Authors: Sukhotin, A., Kovalev, A., Sokolov, E., Sokolova, I. M. Tags: RESEARCH ARTICLE Source Type: research

Evidence that male sea lamprey increase pheromone release after perceiving a competitor [RESEARCH ARTICLE]
We examined how exposure to a major component of the male pheromone, 3keto-petromyzonol sulfate (3kPZS), influenced male pheromone signaling, and whether females had a preference for males that altered their signal. Exposure to 3kPZS, at a concentration of 5x10–10 M, simulated the presence of other male(s) and led to increased 3kPZS release rates within 10 min, followed by a return to baseline levels within 30 min. Exposure also led to increases in hepatic synthesis and circulatory transport of pheromone components. In behavioral assays, females preferred the odor of males that had been exposed to 3kPZS; therefore, m...
Source: Journal of Experimental Biology - June 11, 2020 Category: Biology Authors: Fissette, S. D., Bussy, U., Huerta, B., Buchinger, T. J., Li, W. Tags: RESEARCH ARTICLE Source Type: research

Dinosaur eels build up their fin bones for life on land [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 8, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Response to: The metabolic cost of whistling is low but measurable in dolphins [CORRESPONDENCE]
Michael B. Pedersen, Andreas Fahlman, Alicia Borque-Espinosa, Peter T. Madsen, and Frants H. Jensen (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 8, 2020 Category: Biology Authors: Pedersen, M. B., Fahlman, A., Borque-Espinosa, A., Madsen, P. T., Jensen, F. H. Tags: CORRESPONDENCE Source Type: research

Absolute ethanol intake predicts ethanol preference in Drosophila melanogaster [SHORT COMMUNICATION]
Scarlet J. Park and William W. Ja Factors that mediate ethanol preference in Drosophila melanogaster are not well understood. A major confound has been the use of diverse methods to estimate ethanol consumption. We measured fly consumptive ethanol preference on base diets varying in nutrients, taste and ethanol concentration. Both sexes showed an ethanol preference that was abolished on high nutrient concentration diets. Additionally, manipulating total food intake without altering the nutritive value of the base diet or the ethanol concentration was sufficient to evoke or eliminate ethanol preference. Absolute ethanol in...
Source: Journal of Experimental Biology - June 8, 2020 Category: Biology Authors: Park, S. J., Ja, W. W. Tags: SHORT COMMUNICATION Source Type: research

The metabolic cost of whistling is low but measurable in dolphins [CORRESPONDENCE]
Dawn P. Noren, Marla M. Holt, Robin C. Dunkin, and Terrie M. Willams (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 8, 2020 Category: Biology Authors: Noren, D. P., Holt, M. M., Dunkin, R. C., Willams, T. M. Tags: CORRESPONDENCE Source Type: research

Terrestrial acclimation and exercise lead to bone functional response in Polypterus senegalus pectoral fins [RESEARCH ARTICLE]
Trina Y. Du and Emily M. Standen The ability of bones to sense and respond to mechanical loading is a central feature of vertebrate skeletons. However, the functional demands imposed on terrestrial and aquatic animals differ vastly. The pectoral girdle of the basal actinopterygian fish Polypterus senegalus was previously shown to exhibit plasticity following terrestrial acclimation, but the pectoral fin itself has yet to be examined. We investigated skeletal plasticity in the pectoral fins of P. senegalus after exposure to terrestrial loading. Juvenile fish were divided into three groups: a control group was kept under aq...
Source: Journal of Experimental Biology - June 8, 2020 Category: Biology Authors: Du, T. Y., Standen, E. M. Tags: RESEARCH ARTICLE Source Type: research

Retinal slip compensation of pitch-constrained blue bottle flies flying in a flight mill [SHORT COMMUNICATION]
Shih-Jung Hsu and Bo Cheng In the presence of wind or background image motion, flies are able to maintain a constant retinal slip velocity by regulating flight speed to the extent permitted by their locomotor capacity. Here we investigated the retinal slip compensation of tethered blue bottle flies (Calliphora vomitoria) flying semi-freely along an annular corridor in a magnetically levitated flight mill enclosed by two motorized cylindrical walls. We perturbed the flies' retinal slip by spinning the cylindrical walls, generating bilaterally averaged retinal slip perturbations from –0.3 to 0.3 m s–1 ...
Source: Journal of Experimental Biology - June 8, 2020 Category: Biology Authors: Hsu, S.-J., Cheng, B. Tags: SHORT COMMUNICATION Source Type: research

Fish embryo vulnerability to combined acidification and warming coincides with a low capacity for homeostatic regulation [RESEARCH ARTICLE]
This study implies that the gastrulation period represents a critical transition from inherited (maternal) defenses to active homeostatic regulation, which facilitates enhanced resilience of later stages to environmental factors. (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 5, 2020 Category: Biology Authors: Dahlke, F., Lucassen, M., Bickmeyer, U., Wohlrab, S., Puvanendran, V., Mortensen, A., Chierici, M., Pörtner, H.-O., Storch, D. Tags: Ecophysiology: responses to environmental stressors and change RESEARCH ARTICLE Source Type: research

Hot minnows could struggle to navigate as temperatures rise [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Membrane peroxidation index and maximum lifespan are negatively correlated in fish of the genus Nothobranchius [SHORT COMMUNICATION]
In this study, three fish species of the short-lived annual genus Nothobranchius with different maximum lifespan potential (MLSP) and the longer-lived outgroup species Aphyosemion australe were studied to test whether they conform to the predictions of the longevity–homeoviscous adaptation (LHA) theory of ageing. Lipid analyses were performed in whole-fish samples and the peroxidation index (PIn) for every phospholipid (PL) class and for the whole membrane was calculated. Total PL content was significantly lower in A. australe and N. korthausae, the two species with the highest MLSP, and a negative correlation betwee...
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: de Costa, J., Barja, G., Almaida-Pagan, P. F. Tags: SHORT COMMUNICATION Source Type: research

Reduced exploration capacity despite brain volume increase in warm-acclimated common minnow [RESEARCH ARTICLE]
Libor Zavorka, Barbara Koeck, Tiffany A. Armstrong, Mustafa Soganci, Amelie Crespel, and Shaun S. Killen While evidence suggests that warming may impact cognition of ectotherms, the underlying mechanisms remain poorly understood. A possible but rarely considered mechanism is that the metabolic response of ectotherms to warming is associated with changes in brain morphology and function. Here, we compared aerobic metabolism, brain volume, boldness and accuracy of maze solving of common minnows (Phoxinus phoxinus) acclimated for 8 months to either their current optimal natural (14°C) or warm (20°C) water temper...
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Zavorka, L., Koeck, B., Armstrong, T. A., Soganci, M., Crespel, A., Killen, S. S. Tags: Ecophysiology: responses to environmental stressors and change RESEARCH ARTICLE Source Type: research

Eyelid squinting during food pecking in pigeons [RESEARCH ARTICLE]
Joachim Ostheim, Julia A. M. Delius, and Juan D. Delius The visual control of pecking by pigeons (Columba livia) has latterly been thought to be restricted to the fixation stops interrupting their downward head movements because these stops prevent interference by motion blur. Pigeons were also assumed to close their eyes during the final head thrust of the peck. Here, we re-examined their pecking motions using high-speed video recordings and supplementary provisions that permitted a three-dimensional spatial analysis of the movement, including measurement of pupil diameter and eyelid slit width. The results confirm that ...
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Ostheim, J., Delius, J. A. M., Delius, J. D. Tags: RESEARCH ARTICLE Source Type: research

Responses of activity rhythms to temperature cues evolve in Drosophila populations selected for divergent timing of eclosion [RESEARCH ARTICLE]
In this study, we investigated whether temperature sensitivity of the locomotor activity rhythm evolved in our populations separately from the adult emergence rhythm, with the goal of understanding the extent of similarity (or lack thereof) in circadian organisation underlying the two rhythms. We found that in response to simulated jetlag with temperature cycles, late chronotypes (populations selected for predominant emergence during dusk) indeed re-entrained faster than early chronotypes (populations selected for predominant emergence during dawn) to 6 h phase delays, thereby indicating enhanced sensitivity of the ac...
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Abhilash, L., Kalliyil, A., Sheeba, V. Tags: RESEARCH ARTICLE Source Type: research

Thermo-TRPs and gut microbiota are involved in thermogenesis and energy metabolism during low temperature exposure of obese mice [RESEARCH ARTICLE]
Jing Wen, Tingbei Bo, Xueying Zhang, Zuoxin Wang, and Dehua Wang Ambient temperature and food composition can affect energy metabolism of the host. Thermal transient receptor potential ion channels (thermo-TRPs) can detect temperature signals and are involved in the regulation of thermogenesis and energy homeostasis. Further, the gut microbiota have also been implicated in thermogenesis and obesity. In the present study, we tested the hypothesis that thermo-TRPs and gut microbiota are involved in reducing diet-induced obesity (DIO) during low temperature exposure. C57BL/6J mice in obese (body mass gain>45%), lean (body mass gain
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Wen, J., Bo, T., Zhang, X., Wang, Z., Wang, D. Tags: RESEARCH ARTICLE Source Type: research

Moths use a fuzzy muffler to deaden bat sonar [OUTSIDE JEB]
Joy Putney (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Putney, J. Tags: OUTSIDE JEB Source Type: research

Most salamanders glow: now what? [OUTSIDE JEB]
Brittney G. Borowiec (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Borowiec, B. G. Tags: OUTSIDE JEB Source Type: research

Unpredictability stresses out sea bass [OUTSIDE JEB]
Gina Mantica (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Mantica, G. Tags: OUTSIDE JEB Source Type: research

Ingenious ants reinvent the wheel [OUTSIDE JEB]
Jan Stenum (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 4, 2020 Category: Biology Authors: Stenum, J. Tags: OUTSIDE JEB Source Type: research

Ionoregulatory aspects of the hypoxia-induced osmorespiratory compromise in the euryhaline Atlantic killifish (Fundulus heteroclitus): the effects of salinity [RESEARCH ARTICLE]
Marina Giacomin, John O. Onukwufor, Patricia M. Schulte, and Chris M. Wood The osmorespiratory compromise is a physiological trade-off between the characteristics of the gill that promote respiratory gas-exchange and those that limit passive fluxes of ions and water with the environment. In hypoxia, changes in gill blood flow patterns and functional surface area that increase gas transfer can promote an exacerbation in ion and water fluxes. Our goal was to determine whether the osmorespiratory compromise is flexible, depending on environmental salinity (fresh, isosmotic and sea water) and oxygen levels (hypoxia) in euryhal...
Source: Journal of Experimental Biology - June 2, 2020 Category: Biology Authors: Giacomin, M., Onukwufor, J. O., Schulte, P. M., Wood, C. M. Tags: RESEARCH ARTICLE Source Type: research

Environmental estrogen exposure disrupts sensory processing and nociceptive plasticity in the cephalopod, Euprymna scolopes [SHORT COMMUNICATION]
Stephanie N. Bazarini and Robyn J. Crook Endogenous estrogens affect multiple sensory systems, including those involved in processing noxious and painful stimuli. Extensive evidence demonstrates that estrogenic environmental pollutants have profound, negative effects on growth and reproductive physiology, but there is limited information about how estrogenic pollutants might affect sensory systems known to be modulated by endogenous estrogens. Here, we show that ethinyl estradiol, the most common artificial estrogen found in coastal marine environments, disrupts normal behavioral and neural responses to tissue injury in th...
Source: Journal of Experimental Biology - June 2, 2020 Category: Biology Authors: Bazarini, S. N., Crook, R. J. Tags: SHORT COMMUNICATION Source Type: research

Route-following ants respond to alterations of the view sequence [RESEARCH ARTICLE]
This study investigates whether ant homing behaviour is influenced by alterations in the sequence of views experienced along a familiar route, using the frequency of stop-and-scan behaviour as an indicator of the ant's navigational uncertainty. Ants were trained to forage between their nest and a feeder which they exited through a short channel before proceeding along the homeward route. In tests, ants were collected before entering the nest and released again in the channel, which was placed either in its original location or halfway along the route. Ants exiting the familiar channel in the middle of the route would thus ...
Source: Journal of Experimental Biology - June 2, 2020 Category: Biology Authors: Schwarz, S., Mangan, M., Webb, B., Wystrach, A. Tags: RESEARCH ARTICLE Source Type: research

Carbonic anhydrases are influenced by the size and symbiont identity of the aggregating sea anemone Anthopleura elegantissima [RESEARCH ARTICLE]
This study investigated the effects of symbiosis, body size, and light on CA activity and expression, and suggests that A. elegantissima has a heterotrophy-dominated trophic strategy. We identified putative A. elegantissima CA genes and performed phylogenetic analyses to infer subcellular localization in anemones. We performed experiments on field-collected anemones to compare (1) CA activity and expression from anemones in different symbiotic states, (2) CA activity in brown anemones as a function of size, and (3) CA activity in anemones of different symbiotic states that were exposed to different light intensities. Carbo...
Source: Journal of Experimental Biology - June 2, 2020 Category: Biology Authors: Koch, J. C., Verde, E. A., Weis, V. M. Tags: RESEARCH ARTICLE Source Type: research

It's cold out, but whale sharks stay warm within [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 1, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Testosterone soups up golden-collared manakin roll-snap at expense of endurance [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - June 1, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Androgenic modulation of extraordinary muscle speed creates a performance trade-off with endurance [RESEARCH ARTICLE]
Daniel J. Tobiansky, Meredith C. Miles, Franz Goller, and Matthew J. Fuxjager Performance trade-offs can dramatically alter an organism's evolutionary trajectory by making certain phenotypic outcomes unattainable. Understanding how these trade-offs arise from an animal's design is therefore an important goal of biology. To explore this topic, we studied how androgenic hormones, which regulate skeletal muscle function, influence performance trade-offs relevant to different components of complex reproductive behaviour. We conducted this work in golden-collared manakins (Manacus vitellinus), a neotropical bird in which males...
Source: Journal of Experimental Biology - June 1, 2020 Category: Biology Authors: Tobiansky, D. J., Miles, M. C., Goller, F., Fuxjager, M. J. Tags: RESEARCH ARTICLE Source Type: research

Body temperature stability in the whale shark, the world's largest fish [RESEARCH ARTICLE]
Itsumi Nakamura, Rui Matsumoto, and Katsufumi Sato It is generally assumed that the body temperature of large animals is less likely to change because of their large body size, resulting in a high thermal inertia and a smaller surface area to volume ratio. The goal of this study was to investigate the stability of body temperature in large fish using data from field experiments. We measured the muscle temperatures of free-ranging whale sharks (Rhincodon typus), the largest extant fish globally, and investigated their ectothermic physiology and the stability of their body temperature. The muscle temperature changed substan...
Source: Journal of Experimental Biology - June 1, 2020 Category: Biology Authors: Nakamura, I., Matsumoto, R., Sato, K. Tags: RESEARCH ARTICLE Source Type: research

Spectral sensitivity of cone vision in the diurnal murid Rhabdomys pumilio [RESEARCH ARTICLE]
Annette E. Allen, Joshua W. Mouland, Jessica Rodgers, Beatriz Bano-Otalora, Ronald H. Douglas, Glen Jeffery, Anthony A. Vugler, Timothy M. Brown, and Robert J. Lucas An animal's temporal niche – the time of day at which it is active – is known to drive a variety of adaptations in the visual system. These include variations in the topography, spectral sensitivity and density of retinal photoreceptors, and changes in the eye's gross anatomy and spectral transmission characteristics. We have characterised visual spectral sensitivity in the murid rodent Rhabdomys pumilio (the four-striped grass mouse), which is in...
Source: Journal of Experimental Biology - May 29, 2020 Category: Biology Authors: Allen, A. E., Mouland, J. W., Rodgers, J., Bano-Otalora, B., Douglas, R. H., Jeffery, G., Vugler, A. A., Brown, T. M., Lucas, R. J. Tags: RESEARCH ARTICLE Source Type: research

The effect of ambient oxygen on the thermal performance of a cockroach, Nauphoeta cinerea [RESEARCH ARTICLE]
Emily J. Lombardi, Candice L. Bywater, and Craig R. White The oxygen and capacity-limited thermal tolerance (OCLTT) hypothesis proposes that the thermal tolerance of an animal is shaped by its capacity to deliver oxygen in relation to oxygen demand. Studies testing this hypothesis have largely focused on measuring short-term performance responses in animals under acute exposure to critical thermal maximums. The OCLTT hypothesis, however, emphasises the importance of sustained animal performance over acute tolerance. The present study tested the effect of chronic hypoxia and hyperoxia during development on moderate to long...
Source: Journal of Experimental Biology - May 29, 2020 Category: Biology Authors: Lombardi, E. J., Bywater, C. L., White, C. R. Tags: RESEARCH ARTICLE Source Type: research

Molecular mechanisms of biomineralization in marine invertebrates [REVIEW]
Melody S. Clark Much recent marine research has been directed towards understanding the effects of anthropogenic-induced environmental change on marine biodiversity, particularly for those animals with heavily calcified exoskeletons, such as corals, molluscs and urchins. This is because life in our oceans is becoming more challenging for these animals with changes in temperature, pH and salinity. In the future, it will be more energetically expensive to make marine skeletons and the increasingly corrosive conditions in seawater are expected to result in the dissolution of these external skeletons. However, initial predict...
Source: Journal of Experimental Biology - May 29, 2020 Category: Biology Authors: Clark, M. S. Tags: REVIEW Source Type: research

Fly eyes are not still: a motion illusion in Drosophila flight supports parallel visual processing [RESEARCH ARTICLE]
Wael Salem, Benjamin Cellini, Mark A. Frye, and Jean-Michel Mongeau Most animals shift gaze by a ‘fixate and saccade’ strategy, where the fixation phase stabilizes background motion. A logical prerequisite for robust detection and tracking of moving foreground objects, therefore, is to suppress the perception of background motion. In a virtual reality magnetic tether system enabling free yaw movement, Drosophila implemented a fixate and saccade strategy in the presence of a static panorama. When the spatial wavelength of a vertical grating was below the Nyquist wavelength of the compound eyes, flies drifted co...
Source: Journal of Experimental Biology - May 28, 2020 Category: Biology Authors: Salem, W., Cellini, B., Frye, M. A., Mongeau, J.-M. Tags: RESEARCH ARTICLE Source Type: research

Opportunities during challenging times: comparative studies using meta-analytic approaches and new grants to help early-career researchers [EDITORIAL]
Craig E. Franklin and Hans H. Hoppeler (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 27, 2020 Category: Biology Authors: Franklin, C. E., Hoppeler, H. H. Tags: EDITORIAL Source Type: research

The metabolic response to an immune challenge in a viviparous snake, Sistrurus miliarius [RESEARCH ARTICLE]
Craig M. Lind, Joseph Agugliaro, and Terence M. Farrell Mounting an immune response may be energetically costly and require the diversion of resources away from other physiological processes. Yet, both the metabolic cost of immune responses and the factors that impact investment priorities remain poorly described in many vertebrate groups. For example, although viviparity has evolved many times in vertebrates, the relationship between immune function and pregnancy has been disproportionately studied in placental mammals. To examine the energetic costs of immune activation and the modulation of immune function during pregn...
Source: Journal of Experimental Biology - May 27, 2020 Category: Biology Authors: Lind, C. M., Agugliaro, J., Farrell, T. M. Tags: RESEARCH ARTICLE Source Type: research

The aerodynamic force platform as an ergometer [METHODS [amp ] TECHNIQUES]
Marc E. Deetjen, Diana D. Chin, and David Lentink Animal flight requires aerodynamic power, which is challenging to determine accurately in vivo. Existing methods rely on approximate calculations based on wake flow field measurements, inverse dynamics approaches, or invasive muscle physiological recordings. In contrast, the external mechanical work required for terrestrial locomotion can be determined more directly by using a force platform as an ergometer. Based on an extension of the recent invention of the aerodynamic force platform, we now present a more direct method to determine the in vivo aerodynamic power by taki...
Source: Journal of Experimental Biology - May 27, 2020 Category: Biology Authors: Deetjen, M. E., Chin, D. D., Lentink, D. Tags: METHODS [amp ] TECHNIQUES Source Type: research

Mechanical fatigue fractures bivalve shells [RESEARCH ARTICLE]
R. L. Crane and M. W. Denny Mollusk shells protect against diverse environmental and predatory physical threats, from one-time impacts to chronic, low-magnitude stresses. The effectiveness of shells as armor is often quantified with a test of shell strength: increasing force is applied until catastrophic fracture. This test does not capture the potential role of fatigue, a process by which chronic or repeated, low-magnitude forces weaken and break a structure. We quantified the strength and fatigue resistance of California mussel (Mytilus californianus) shells. Shells were fatigue tested until catastrophic failure by eith...
Source: Journal of Experimental Biology - May 27, 2020 Category: Biology Authors: Crane, R. L., Denny, M. W. Tags: RESEARCH ARTICLE Source Type: research

Diving apart together: call propagation in diving long-finned pilot whales [RESEARCH ARTICLE]
Annebelle C. M. Kok, Lisette van Kolfshoten, James A. Campbell, Alexander M. von Benda-Beckmann, Patrick J. O. Miller, Hans Slabbekoorn, and Fleur Visser Group-living animals must communicate to stay in contact. In long-finned pilot whales, there is a trade-off between the benefits of foraging individually at depth and the formation of tight social groups at the surface. Using theoretical modelling and empirical data of tagged pairs within a group, we examined the potential of pilot whale social calls to reach dispersed group members during foraging periods. Both theoretical predictions and empirical data of tag pairs sho...
Source: Journal of Experimental Biology - May 27, 2020 Category: Biology Authors: Kok, A. C. M., van Kolfshoten, L., Campbell, J. A., von Benda-Beckmann, A. M., Miller, P. J. O., Slabbekoorn, H., Visser, F. Tags: RESEARCH ARTICLE Source Type: research

Ontogenetic variation in the hearing sensitivity of black sea bass (Centropristis striata) and the implications of anthropogenic sound on behavior and communication [RESEARCH ARTICLE]
This study is a first step in understanding the effects of anthropogenic noise on C. striata by determining the auditory bandwidth and thresholds of this species using auditory evoked potentials (AEPs), creating pressure and acceleration audiograms. These physiological tests were conducted on wild-caught C. striata in three size/age categories. Results showed that juvenile C. striata significantly had the lowest thresholds, with hearing sensitivity decreasing in the larger size classes. Furthermore, Centropristis striata has fairly sensitive hearing relative to other related species. Preliminary investigations into the mec...
Source: Journal of Experimental Biology - May 27, 2020 Category: Biology Authors: Stanley, J. A., Caiger, P. E., Phelan, B., Shelledy, K., Mooney, T. A., Van Parijs, S. M. Tags: RESEARCH ARTICLE Source Type: research

Polarized light sensitivity in Pieris rapae is dependent on both color and intensity [RESEARCH ARTICLE]
Adam J. Blake, Gina S. Hahn, Hayley Grey, Shelby A. Kwok, Deby McIntosh, and Gerhard Gries There is an ever increasing number of arthropod taxa shown to have polarization sensitivity throughout their compound eyes. However, the downstream processing of polarized reflections from objects is not well understood. The small white butterfly, Pieris rapae, has been demonstrated to exploit foliar polarized reflections, specifically the degree of linear polarization (DoLP), to recognize host plants. The well-described visual system of P. rapae includes several photoreceptor types (red, green, blue) that are sensitive to polarized ...
Source: Journal of Experimental Biology - May 27, 2020 Category: Biology Authors: Blake, A. J., Hahn, G. S., Grey, H., Kwok, S. A., McIntosh, D., Gries, G. Tags: RESEARCH ARTICLE Source Type: research

Colin James Pennycuick (1933-2019) [OBITUARY]
Anders Hedenstròˆm and Geoffrey Spedding (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Hedenström, A., Spedding, G. Tags: OBITUARY Source Type: research

Fatigue pushes mussel shells to the brink over time [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

The effect of ecological factors on eye morphology in the western rainbowfish, Melanotaenia australis [RESEARCH ARTICLE]
Thomas J. Lisney, Shaun P. Collin, and Jennifer L. Kelley Ecological factors such as spatial habitat complexity and diet can explain variation in visual morphology, but few studies have sought to determine whether visual specialisation can occur among populations of the same species. We used a small Australian freshwater fish (the western rainbowfish, Melanotaenia australis) to determine whether populations showed variation in eye size and eye position, and whether this variation could be explained by environmental (light availability, turbidity) and ecological (predation risk, habitat complexity, invertebrate abundance) ...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Lisney, T. J., Collin, S. P., Kelley, J. L. Tags: RESEARCH ARTICLE Source Type: research

Maximum aerodynamic force production by the wandering glider dragonfly (Pantala flavescens, Libellulidae) [RESEARCH ARTICLE]
Guanting Su, Robert Dudley, Tianyu Pan, Mengzong Zheng, Liansong Peng, and Qiushi Li Maximum whole-body force production can influence behavioral outcomes for volant taxa, and may also be relevant to aerodynamic optimization in microair vehicles. Here, we describe a new method for measuring maximum force production in free-flying animals, and present associated data for the wandering glider dragonfly. Flight trajectories were repeatedly acquired from pull-up responses by insects dropped in mid-air with submaximal loads attached beneath the center of body mass. Forces were estimated from calculations of the maximum time-ave...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Su, G., Dudley, R., Pan, T., Zheng, M., Peng, L., Li, Q. Tags: RESEARCH ARTICLE Source Type: research

Effect of ambient temperature on sleep breathing phenotype in mice: the role of orexins [RESEARCH ARTICLE]
Chiara Berteotti, Viviana Lo Martire, Sara Alvente, Stefano Bastianini, Gabriele Matteoli, Alessandro Silvani, and Giovanna Zoccoli The loss of orexinergic neurons, releasing orexins, results in narcolepsy. Orexins participate in the regulation of many physiological functions, and their role as wake-promoting molecules has been widely described. Less is known about the involvement of orexins in body temperature and respiratory regulation. The aim of this study was to investigate whether orexin peptides modulate respiratory regulation as a function of ambient temperature (T°a) during different sleep stages. Respiratory ...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Berteotti, C., Lo Martire, V., Alvente, S., Bastianini, S., Matteoli, G., Silvani, A., Zoccoli, G. Tags: RESEARCH ARTICLE Source Type: research

Effects of membrane fatty acid composition on cellular metabolism and oxidative stress in dermal fibroblasts from small and large breed dogs [RESEARCH ARTICLE]
Ana Gabriela Jimenez, Joshua D. Winward, Kenneth E. Walsh, and Alex M. Champagne There is ample evidence that cell membrane architecture contributes to metabolism and aging in animals, however the aspects of this architecture that determine the rate of metabolism and longevity are still being debated. The "membrane pacemaker" hypotheses of metabolism and aging, respectively, suggest that increased lipid unsaturation and large amounts of polyunsaturated fatty acids (PUFAs) in cell membranes increases the cellular metabolic rate as well as the vulnerability of the cell to oxidative damage, thus increasing organisma...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Jimenez, A. G., Winward, J. D., Walsh, K. E., Champagne, A. M. Tags: RESEARCH ARTICLE Source Type: research

Hypoxia acclimation alters reactive oxygen species homeostasis and oxidative status in estuarine killifish (Fundulus heteroclitus) [RESEARCH ARTICLE]
We examined how exposure to acute hypoxia (2 kPa O2) and subsequent reoxygenation (to 20 kPa O2) affects redox status, oxidative damage, and antioxidant defenses in estuarine killifish (Fundulus heteroclitus), and whether these effects were ameliorated or potentiated by prolonged (28 day) acclimation to either constant hypoxia or intermittent cycles of nocturnal hypoxia (12 h normoxia: 12 h hypoxia). Acute hypoxia and reoxygenation led to some modest and transient changes in redox status, increases in oxidized glutathione, depletion of scavenging capacity, and oxidative damage to lipids in the skeletal muscle. The liver ha...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Borowiec, B. G., Scott, G. R. Tags: RESEARCH ARTICLE Source Type: research

Mussels' acclimatization to high, variable temperatures is lost slowly upon transfer to benign conditions [RESEARCH ARTICLE]
This study explored the rate at which field-acclimatization states are lost when temperature variability is minimized during constant submersion. California mussels (Mytilus californianus) with different acclimatization states were collected from high- and low-zone sites (~12°C vs. ~5°C daily temperature ranges, respectively) and then kept submerged at 15°C for eight weeks. Each week, mussels’ cardiac thermal performance was measured as a metric of acclimatization state; critical (Tcrit) and flatline (FLT) temperatures were recorded. Across eight weeks of constant submersion high-zone mussels’ mean ...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Moyen, N. E., Somero, G. N., Denny, M. W. Tags: RESEARCH ARTICLE Source Type: research

A novel microRNA and its PFK target control growth length in the freshwater shrimp (Neocaridina heteropoda) [RESEARCH ARTICLE]
Ran Li, Jieyang Weng, Liqi Ren, Xin Wang, Qinghao Meng, Liyan Wang, and Jinsheng Sun MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression and play roles in a wide range of physiological processes, including ontogenesis. Herein, we discovered a novel microRNA, novel miR-26, which inhibits translation of the phosphofructokinase (PFK) gene by targeting the 3’ untranslated region (UTR) of pfk directly, thereby inhibiting the molting and body length growth of the freshwater shrimp (Neocaridina heteropoda). Lowering expression of the PFK gene by RNA interference (RNAi) led to a longer ecdys...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Li, R., Weng, J., Ren, L., Wang, X., Meng, Q., Wang, L., Sun, J. Tags: RESEARCH ARTICLE Source Type: research

Pygmy mouse songs reveal anatomical innovations underlying acoustic signal elaboration in rodents [RESEARCH ARTICLE]
Tobias Riede and Bret Pasch Elaborate animal communication displays are often accompanied by morphological and physiological innovations. In rodents, acoustic signals used in reproductive contexts are produced by two distinct mechanisms, but the underlying anatomy that facilitates such divergence is poorly understood. ‘Audible’ vocalizations with spectral properties between 500 Hz and 16 kHz are thought to be produced by flow-induced vocal fold vibrations, whereas ‘ultrasonic’ vocalizations with fundamental frequencies above 19 kHz are produced by an aerodynamic whistle mechanism. Baiomyine mice (ge...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Riede, T., Pasch, B. Tags: RESEARCH ARTICLE Source Type: research

Discrete modulation of antipredatory and agonistic behaviors by sensory communication signals in juvenile crayfish [RESEARCH ARTICLE]
Alexis C. Exum, Lucky M. Sun, and Jens Herberholz We investigated how the exchange of sensory signals modulates the individual behaviors of juvenile crayfish in an anti-predatory context as well as during intraspecific agonistic encounters. We first compared crayfish housed in total sensory isolation or in pairs with access to chemical and visual cues. After one week of housing, we analyzed their individual responses to a visual danger signal while they were foraging. We found that crayfish previously housed in pairs with exchange of sensory signals responded to a simulated predator attack predominately with freezing behav...
Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Exum, A. C., Sun, L. M., Herberholz, J. Tags: RESEARCH ARTICLE Source Type: research