Limits to sustained energy intake. XXXI. Effect of graded levels of dietary fat on lactation performance in Swiss mice [RESEARCH ARTICLE]
Yi Huang, Jazmin Osorio Mendoza, Catherine Hambly, Baoguo Li, Zengguang Jin, Li Li, Moshen Madizi, Sumei Hu, and John R. Speakman The heat dissipation limit theory predicts that lactating female mice consuming diets with lower specific dynamic action (SDA) should have enhanced lactation performance. Dietary fat has lower SDA than other macronutrients. Here we tested the effects of graded dietary fat levels on lactating Swiss mice. We fed females five diets varying in fat content from 8.3 to 66.6%. Offspring of mothers fed diets of 41.7% fat and above were heavier and fatter at weaning compared with those of 8.3 and 25% fa...
Source: Journal of Experimental Biology - May 22, 2020 Category: Biology Authors: Huang, Y., Mendoza, J. O., Hambly, C., Li, B., Jin, Z., Li, L., Madizi, M., Hu, S., Speakman, J. R. Tags: RESEARCH ARTICLE Source Type: research

A fast and effective method for dissecting parasitic spores: myxozoans as an example [METHODS [amp ] TECHNIQUES]
Qingxiang Gu, Yang Liu, Yanhua Zhai, and Zemao Gu Disassembling parasitic spores and acquiring the main subunits for analysis is a prerequisite for a deep understanding of the basic biology of parasites. Herein, we present a fast and efficient method to dissect myxospores in a few steps, which mainly involves sonication, and sucrose and Percoll density gradient ultracentrifugation. We tested our method on three myxozoan species and demonstrate that this method allows the dismembering of myxospores, and the isolation of intact and clean nematocysts and shell valves within 2 h at low cost. This new tool will facilitate...
Source: Journal of Experimental Biology - May 22, 2020 Category: Biology Authors: Gu, Q., Liu, Y., Zhai, Y., Gu, Z. Tags: METHODS [amp ] TECHNIQUES Source Type: research

Both sexes produce sounds in vocal fish species: testing the hypothesis in the pygmy gourami (labyrinth fishes) [RESEARCH ARTICLE]
Noemie Liesch and Friedrich Ladich In vocal fish species, males possess larger sound-generating organs and signal acoustically with pronounced sex-specific differences. Sound production is known in two out of three species of croaking gouramis (Trichopsis vittata and T. schalleri). The present study investigates sex-specific differences in sonic organs, vocalizing behaviour and sounds emitted in the third species, the pygmy gourami, T. pumila, in order to test the hypothesis that females are able to vocalize despite their less-developed sonic organs, and despite contradictory reports. Croaking gouramis stretch and pluck t...
Source: Journal of Experimental Biology - May 20, 2020 Category: Biology Authors: Liesch, N., Ladich, F. Tags: RESEARCH ARTICLE Source Type: research

On the regeneration of fish scales: structure and mechanical behavior [RESEARCH ARTICLE]
S. Ghods, S. Waddell, E. Weller, C. Renteria, H.-Y. Jiang, J. M. Janak, S. S. Mao, T. J. Linley, and D. Arola Fish scales serve as a dermal armor that provides protection from physical injury. Owing to a number of outstanding properties, fish scales are inspiring new concepts for layered engineered materials and next-generation flexible armors. Although past efforts have primarily focused on the structure and mechanical behavior of ontogenetic scales, the structure–property relationships of regenerated scales have received limited attention. In the present study, common carp (Cyprinus carpio) acquired from the wild ...
Source: Journal of Experimental Biology - May 20, 2020 Category: Biology Authors: Ghods, S., Waddell, S., Weller, E., Renteria, C., Jiang, H.- Y., Janak, J. M., Mao, S. S., Linley, T. J., Arola, D. Tags: RESEARCH ARTICLE Source Type: research

Feisty squid and fish flash back to dazzle predatory elephant seals [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 19, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Flash and grab: deep-diving southern elephant seals trigger anti-predator flashes in bioluminescent prey [RESEARCH ARTICLE]
Pauline Goulet, Christophe Guinet, Claudio Campagna, Julieta Campagna, Peter Lloyd Tyack, and Mark Johnson Bioluminescence, which occurs in approximately 80% of the world's mesopelagic fauna, can take the form of a low-intensity continuous glow (e.g. for counter-illumination or signalling) or fast repetitions of brighter anti-predatory flashes. The southern elephant seal (SES) is a major consumer of mesopelagic organisms, in particular the abundant myctophid fish, yet the fine-scale relationship between this predator's foraging behaviour and bioluminescent prey remains poorly understood. We hypothesised that brief, intens...
Source: Journal of Experimental Biology - May 19, 2020 Category: Biology Authors: Goulet, P., Guinet, C., Campagna, C., Campagna, J., Tyack, P. L., Johnson, M. Tags: RESEARCH ARTICLE Source Type: research

Neural dysfunction correlates with heat coma and CTmax in Drosophila but does not set the boundaries for heat stress survival [RESEARCH ARTICLE]
Lisa B. Jorgensen, R. Meldrum Robertson, and Johannes Overgaard When heated, insects lose coordinated movement followed by the onset of heat coma (CTmax). These traits are popular measures to quantify inter- and intraspecific differences in insect heat tolerance, and CTmax correlate well with current species distributions of insects, including Drosophila. Here we examined the function of the central nervous system (CNS) in five species of Drosophila with different heat tolerances, while they were exposed to either constant high temperature or a gradual increasing temperature (ramp). Tolerant species were able to preserve C...
Source: Journal of Experimental Biology - May 19, 2020 Category: Biology Authors: Jorgensen, L. B., Robertson, R. M., Overgaard, J. Tags: RESEARCH ARTICLE Source Type: research

Atrioventricular block, due to reduced ventricular excitability, causes the depression of fish heart rate in fish at critically high temperatures [RESEARCH ARTICLE]
Jaakko Haverinen and Matti Vornanen At critically high temperature, cardiac output in fish collapses due to depression of heart rate (bradycardia). However, the cause of bradycardia remains unresolved. To this end rainbow trout (Oncorhynchus mykiss; acclimated at +12°C) were exposed to acute warming, while electrocardiograms were recorded. From +12℃ to +25.3℃, electrical excitation between different parts of the heart was coordinated but above +25.3℃ atrial and ventricular beating rates became partly dissociated due to 2:1 atrioventricular (AV) block. With further warming atrial rate increased to the peak value o...
Source: Journal of Experimental Biology - May 19, 2020 Category: Biology Authors: Haverinen, J., Vornanen, M. Tags: RESEARCH ARTICLE Source Type: research

Cyber-frog leg leaps out of reality [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 18, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Magnetoreception in fishes: the effect of magnetic pulses on orientation of juvenile Pacific salmon [RESEARCH ARTICLE]
In this study, juvenile Chinook salmon (Oncorhynchus tshawytscha) were exposed to a brief but strong magnetic pulse capable of altering the magnetic dipole moment of biogenic magnetite. Orientation behaviour of pulsed fish and untreated control fish was then compared in a magnetic coil system under two conditions: (1) the local magnetic field and (2) a magnetic field that exists near the southern boundary of the natural oceanic range of Chinook salmon. In the local field, no significant difference existed between the orientation of the control and pulsed groups. By contrast, orientation of the two groups was significantly ...
Source: Journal of Experimental Biology - May 18, 2020 Category: Biology Authors: Naisbett-Jones, L. C., Putman, N. F., Scanlan, M. M., Noakes, D. L. G., Lohmann, K. J. Tags: RESEARCH ARTICLE Source Type: research

Learning of bimodal versus unimodal signals in restrained bumble bees [RESEARCH ARTICLE]
Andre J. Riveros, Anne S. Leonard, Wulfila Gronenberg, and Daniel R. Papaj Similar to animal communication displays, flowers emit complex signals that attract pollinators. Signal complexity could lead to higher cognitive load for pollinators, impairing performance, or might benefit them by facilitating learning, memory and decision making. Here, we evaluated learning and memory in foragers of the bumble bee Bombus impatiens trained to simple (unimodal) versus complex (bimodal) signals under restrained conditions. Use of a proboscis extension response protocol enabled us to control the timing and duration of stimuli presen...
Source: Journal of Experimental Biology - May 18, 2020 Category: Biology Authors: Riveros, A. J., Leonard, A. S., Gronenberg, W., Papaj, D. R. Tags: RESEARCH ARTICLE Source Type: research

In vitro virtual reality: an anatomically explicit musculoskeletal simulation powered by in vitro muscle using closed-loop tissue-software interaction [METHODS [amp ] TECHNIQUES]
Christopher T. Richards and Enrico A. Eberhard Muscle force–length dynamics are governed by intrinsic contractile properties, motor stimulation and mechanical load. Although intrinsic properties are well characterised, physiologists lack in vitro instrumentation to account for combined effects of limb inertia, musculoskeletal architecture and contractile dynamics. We introduce in vitro virtual reality (in vitro-VR) which enables in vitro muscle tissue to drive a musculoskeletal jumping simulation. In hardware, muscle force from a frog plantaris was transmitted to a software model where joint torques, inertia and gro...
Source: Journal of Experimental Biology - May 18, 2020 Category: Biology Authors: Richards, C. T., Eberhard, E. A. Tags: Comparative biomechanics of movement METHODS [amp ] TECHNIQUES Source Type: research

An {alpha}7-related nicotinic acetylcholine receptor mediates the ciliary arrest response in pharyngeal gill slits of Ciona [RESEARCH ARTICLE]
Kei Jokura, Junko M. Nishino, Michio Ogasawara, and Atsuo Nishino Ciliary movement is a fundamental process to support animal life, and the movement pattern may be altered in response to external stimuli under the control of nervous systems. Juvenile and adult ascidians have ciliary arrays around their pharyngeal gill slits (stigmata), and continuous beating is interrupted for seconds by mechanical stimuli on other parts of the body. Although it has been suggested that neural transmission to evoke ciliary arrest is cholinergic, its molecular basis has not yet been elucidated in detail. Here, we attempted to clarify the mo...
Source: Journal of Experimental Biology - May 18, 2020 Category: Biology Authors: Jokura, K., Nishino, J. M., Ogasawara, M., Nishino, A. Tags: RESEARCH ARTICLE Source Type: research

Effect of stimulus height on cockroach optomotor response [RESEARCH ARTICLE]
Juha Nuutila, Anna E. Honkanen, Kyösti Heimonen, and Matti Weckström Using tethered American cockroaches walking on a trackball in a spherical virtual reality environment, we tested optomotor responses to horizontally moving black-and-white gratings of different vertical extent under six different light intensities. We found that shortening the vertical extent of the wide-field stimulus grating within a light level weakened response strength, reduced average velocity and decreased angular walking distance. Optomotor responses with the vertically shortened stimuli persisted down to light intensity levels of 0.05 l...
Source: Journal of Experimental Biology - May 18, 2020 Category: Biology Authors: Nuutila, J., Honkanen, A. E., Heimonen, K., Weckström, M. Tags: RESEARCH ARTICLE Source Type: research

The OxymiR response to oxygen limitation: a comparative microRNA perspective [REVIEW]
Hanane Hadj-Moussa and Kenneth B. Storey From squid at the bottom of the ocean to humans at the top of mountains, animals have adapted to diverse oxygen-limited environments. Surviving these challenging conditions requires global metabolic reorganization that is orchestrated, in part, by microRNAs that can rapidly and reversibly target all biological functions. Herein, we review the involvement of microRNAs in natural models of anoxia and hypoxia tolerance, with a focus on the involvement of oxygen-responsive microRNAs (OxymiRs) in coordinating the metabolic rate depression that allows animals to tolerate reduced oxygen l...
Source: Journal of Experimental Biology - May 18, 2020 Category: Biology Authors: Hadj-Moussa, H., Storey, K. B. Tags: REVIEW Source Type: research

Correction: Exposure to hot temperatures during lactation in Swiss mice stunts offspring growth and decreases future reproductive performance of female offspring [CORRECTION]
Meng-Huan Bao, Li-Bing Chen, Catherine Hambly, John R. Speakman, and Zhi-Jun Zhao (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 15, 2020 Category: Biology Authors: Bao, M.-H., Chen, L.-B., Hambly, C., Speakman, J. R., Zhao, Z.-J. Tags: CORRECTION Source Type: research

Route learning during tandem running in the rock ant Temnothorax albipennis [RESEARCH ARTICLE]
Takao Sasaki, Leo Danczak, Beth Thompson, Trisha Morshed, and Stephen C. Pratt Many animals use information from conspecifics to change their behavior in adaptive ways. When a rock ant, Temnothorax albipennis, finds food, she returns to her colony and uses a method called tandem running to lead nestmates, one at a time, from the nest to the food. In this way, naive ants can learn the location of a food source. Less clear is whether they also learn navigational cues that guide them from nest to food, although this is often assumed. We tested this idea by tracing the routes of individually marked ants as they followed tande...
Source: Journal of Experimental Biology - May 15, 2020 Category: Biology Authors: Sasaki, T., Danczak, L., Thompson, B., Morshed, T., Pratt, S. C. Tags: RESEARCH ARTICLE Source Type: research

Terrestrial acclimation and exercise lead to bone functional response in Polypterus 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 Polypterus after exposure to terrestrial loading. Juvenile fish were divided into three groups: a control group was kept under aquat...
Source: Journal of Experimental Biology - May 15, 2020 Category: Biology Authors: Du, T. Y., Standen, E. M. Tags: RESEARCH ARTICLE Source Type: research

Asymmetrical gait kinematics of free-ranging callitrichines in response to changes in substrate diameter and orientation [RESEARCH ARTICLE]
Noah T. Dunham, Allison McNamara, Liza J. Shapiro, Taylor Phelps, and Jesse W. Young Arboreal environments present considerable biomechanical challenges for animals moving and foraging among substrates varying in diameter, orientation, and compliance. Most studies of quadrupedal gait kinematics in primates and other arboreal mammals have focused on symmetrical walking gaits and the significance of diagonal sequence gaits. Considerably less research has examined asymmetrical gaits, despite their prevalence in small-bodied arboreal taxa. Here we examine whether and how free-ranging callitrichine primates adjust asymmetrical ...
Source: Journal of Experimental Biology - May 15, 2020 Category: Biology Authors: Dunham, N. T., McNamara, A., Shapiro, L. J., Phelps, T., Young, J. W. Tags: RESEARCH ARTICLE Source Type: research

Functional effect of vaterite - The presence of an alternative crystalline structure in otoliths alters escape kinematics of the brown trout [RESEARCH ARTICLE]
Matthias Vignon and Jean-Christophe Aymes The fast-start escape response is the main locomotor behavior observed in fish to evade predatory attacks and thereby increase their probability of survival. Thus far, this high speed sensory motor control has been extensively studied in relation to extrinsic factors. In contrast, there has been surprisingly little consideration for intrinsic individuals factors that can mediate sensorial perception, such as inter-individual variability in mechanosensory systems. The inner ear of teleost fishes is composed of otoliths that play an important role in hearing and balance functions. Wh...
Source: Journal of Experimental Biology - May 15, 2020 Category: Biology Authors: Vignon, M., Aymes, J.-C. Tags: RESEARCH ARTICLE Source Type: research

Complex multi-modal sensory integration and context specificity in colour preferences of a pierid butterfly [RESEARCH ARTICLE]
G. S. Balamurali, Saloni Rose, Hema Somanathan, and Ullasa Kodandaramaiah Innate colour preferences in insects were long considered to be a non-flexible representation of a floral ‘search image’ guiding insects to flowers during initial foraging trips. However, these colour preferences have recently been shown to be modulated by multi-sensory integration of information. Using experiments on the butterfly Catopsilia pomona (Common Emigrant), we demonstrate that cross-modal integration of information not only affects colour preferences but also colour learning, and in a sex-specific manner. We show that spontaneo...
Source: Journal of Experimental Biology - May 15, 2020 Category: Biology Authors: Balamurali, G. S., Rose, S., Somanathan, H., Kodandaramaiah, U. Tags: RESEARCH ARTICLE 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 metabolic response of ectotherms to warming associate with changes in brain morphology and functioning. Here we compared aerobic metabolism, volume of brain, boldness, and accuracy of maze solving of common minnows (Phoxinus phoxinus) acclimated for eight months to either their current optimal natural (14 °C) or warm (20 °C) water tempera...
Source: Journal of Experimental Biology - May 15, 2020 Category: Biology Authors: Zavorka, L., Koeck, B., Armstrong, T. A., Soganci, M., Crespel, A., Killen, S. S. Tags: RESEARCH ARTICLE Source Type: research

Spontaneous quantity discrimination of artificial flowers by foraging honeybees [RESEARCH ARTICLE]
Scarlett R. Howard, Jürgen Schramme, Jair E. Garcia, Leslie Ng, Aurore Avargues-Weber, Andrew D. Greentree, and Adrian G. Dyer Many animals need to process numerical and quantity information in order to survive. Spontaneous quantity discrimination allows differentiation between two or more quantities without reinforcement or prior training on any numerical task. It is useful for assessing food resources, aggressive interactions, predator avoidance and prey choice. Honeybees have previously demonstrated landmark counting, quantity matching, use of numerical rules, quantity discrimination and arithmetic, but have not been...
Source: Journal of Experimental Biology - May 14, 2020 Category: Biology Authors: Howard, S. R., Schramme, J., Garcia, J. E., Ng, L., Avargues-Weber, A., Greentree, A. D., Dyer, A. G. Tags: RESEARCH ARTICLE Source Type: research

Does the New Zealand rockwren (Xenicus gilviventris) hibernate? [RESEARCH ARTICLE]
In this study, we examined the thermal physiology of the endangered New Zealand rockwren (Xenicus gilviventris), a member of the Acanthisittidae, a family unique to New Zealand. This family, derived from Gondwana, is thought to be the sister taxon to all other passerines. Rockwrens permanently reside above the climatic timberline at altitudes from 1000 to 2900 m in the mountains of South Island. They feed on invertebrates and in winter face ambient temperatures far below freezing and deep deposits of snow. Their body temperature and rate of metabolism are highly variable. The rockwrens in our study regulated their bod...
Source: Journal of Experimental Biology - May 14, 2020 Category: Biology Authors: McNab, B. K., Weston, K. A. Tags: RESEARCH ARTICLE Source Type: research

A simple device to immobilize protists for electrophysiology and microinjection [METHODS [amp ] TECHNIQUES]
We present a simple device to mechanically immobilize motile cells such as ciliates. It can be used in particular for intracellular electrophysiology and microinjection. A transparent filter with holes smaller than the specimen is stretched over an outlet. A flow is induced by either a peristaltic pump or a depressurized tank, mechanically entraining cells to the bottom, where they immobilize against the filter. The cells start swimming again as soon as the flow is stopped. We demonstrate the device by recording action potentials in Paramecium and injecting a fluorescent dye in the cytosol. (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 14, 2020 Category: Biology Authors: Kulkarni, A., Elices, I., Escoubet, N., Pontani, L.-L., Prevost, A. M., Brette, R. Tags: METHODS [amp ] TECHNIQUES Source Type: research

Alkaline guts protect sea urchin larvae from infection [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 13, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Alkaline guts contribute to immunity during exposure to acidified seawater in the sea urchin larva [RESEARCH ARTICLE]
Meike Stumpp, Inga Petersen, Femke Thoben, Jia-Jiun Yan, Matthias Leippe, and Marian Y. Hu Larval stages of members of the Abulacraria superphylum including echinoderms and hemichordates have highly alkaline midguts. To date, the reason for the evolution of such extreme pH conditions in the gut of these organisms remains unknown. Here, we test the hypothesis that, analogous to the acidic stomachs of vertebrates, these alkaline conditions may represent a first defensive barrier to protect from environmental pathogens. pH-optimum curves for five different species of marine bacteria demonstrated a rapid decrease in prolifera...
Source: Journal of Experimental Biology - May 13, 2020 Category: Biology Authors: Stumpp, M., Petersen, I., Thoben, F., Yan, J.-J., Leippe, M., Hu, M. Y. Tags: RESEARCH ARTICLE Source Type: research

The sonar beam of Macrophyllum macrophyllum implies ecological adaptation under phylogenetic constraint [RESEARCH ARTICLE]
Mads Nedergaard Olsen, Annemarie Surlykke, and Lasse Jakobsen All animals are adapted to their ecology within the bounds of their evolutionary heritage. Echolocating bats clearly show such adaptations and boundaries through their biosonar call design. Adaptations include not only the overall time-frequency structure, but also the shape of the emitted echolocation beam. Macrophyllum macrophyllum is unique within the phyllostomid family, being the only species to predominantly hunt for insects in the open, on or above water and as such it presents an interesting case for comparing the impact of phylogeny and ecology as it or...
Source: Journal of Experimental Biology - May 12, 2020 Category: Biology Authors: Olsen, M. N., Surlykke, A., Jakobsen, L. Tags: RESEARCH ARTICLE Source Type: research

Conversation moves on: revisiting early-career researchers and a new focus on fieldwork [EDITORIAL]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Knight, K. Tags: EDITORIAL Source Type: research

In the field: an interview with Craig Franklin [CONVERSATION]
Craig Franklin is a Professor at The University of Queensland, Australia where he investigates the physiological and behavioural responses of fish, frogs and reptiles to changing environmental conditions. He completed his undergraduate degree in Zoology and his PhD at The University of Canterbury, New Zealand, before undertaking postdocs in New Zealand, Australia and the UK. Franklin talks to us about his experiences working in field locations ranging from Antarctica to tropical Northern Australia. (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Tags: CONVERSATION Source Type: research

Simulated larvae reveal why fish fry lose their dinner [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Flying lizards plan ahead to avoid clutter [OUTSIDE JEB]
Jake Socha (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Socha, J. Tags: OUTSIDE JEB Source Type: research

Near-equal compressibility of liver oil and seawater minimises buoyancy changes in deep-sea sharks and chimaeras [RESEARCH ARTICLE]
Imants G. Priede, Rhoderick W. Burgass, Manolis Mandalakis, Apostolos Spyros, Petros Gikas, Finlay Burns, and Jim Drewery Whereas upper ocean pelagic sharks are negatively buoyant and must swim continuously to generate lift from their fins, deep-sea sharks float or swim slowly buoyed up by large volumes of low-density oils in their livers. Investigation of the pressure, volume, temperature (PVT) relationships for liver oils of 10 species of deep-sea Chondrichthyes shows that the density difference between oil and seawater, , remains almost constant with pressure down to full ocean depth (11 km, 1100 bar), theore...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Priede, I. G., Burgass, R. W., Mandalakis, M., Spyros, A., Gikas, P., Burns, F., Drewery, J. Tags: RESEARCH ARTICLE Source Type: research

Wolbachia-infected ant colonies have increased reproductive investment and an accelerated life cycle [RESEARCH ARTICLE]
Rohini Singh and Timothy A. Linksvayer Wolbachia is a widespread genus of maternally transmitted endosymbiotic bacteria that often manipulates the reproductive strategy and life history of its hosts to favor its own transmission. Wolbachia-mediated phenotypic effects are well characterized in solitary hosts, but effects in social hosts are unclear. The invasive pharaoh ant, Monomorium pharaonis, shows natural variation in Wolbachia infection between colonies and can be readily bred under laboratory conditions. We previously showed that Wolbachia-infected pharaoh ant colonies had more queen-biased sex ratios than uninfecte...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Singh, R., Linksvayer, T. A. Tags: RESEARCH ARTICLE Source Type: research

The brains of six African mole-rat species show divergent responses to hypoxia [RESEARCH ARTICLE]
This study is the first to examine the molecular response to low oxygen in six different species of hypoxia-tolerant mole-rats from sub-Saharan Africa. Protein carbonylation, a known marker of DNA damage (hydroxy-2'-deoxyguanosine), and antioxidant capacity did not change following hypoxia but HIF-1 protein levels increased significantly in the brains of two species. Nearly 30 miRNAs known to play roles in hypoxia tolerance were differentially regulated in a species-specific manner. The miRNAs exhibiting the strongest response to low oxygen stress inhibit apoptosis and regulate neuroinflammation, likely providing neuroprot...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Logan, S. M., Szereszewski, K. E., Bennett, N. C., Hart, D. W., van Jaarsveld, B., Pamenter, M. E., Storey, K. B. Tags: RESEARCH ARTICLE Source Type: research

The hydrodynamic regime drives flow reversals in suction-feeding larval fishes during early ontogeny [RESEARCH ARTICLE]
In this study, we used numerical simulations to investigate the hydrodynamic mechanisms responsible for the failure to feed caused by this in-and-out prey movement. Detailed kinematics of the expanding mouth during prey capture by larval Sparus aurata were used to parameterize age-specific numerical models of the flows inside the mouth. These models revealed that for small larvae which expand their mouth slowly, fluid entering the mouth cavity is expelled through the mouth before it is closed, resulting in flow reversal at the orifice. This relative efflux of water through the mouth was>8% of the influx through the mout...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Krishnan, K., Nafi, A. S., Gurka, R., Holzman, R. Tags: RESEARCH ARTICLE Source Type: research

Full bellies stave off climate change [OUTSIDE JEB]
Till Harter (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Harter, T. Tags: OUTSIDE JEB Source Type: research

Lizard athletes have a home-field advantage [OUTSIDE JEB]
Noah Bressman (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Bressman, N. Tags: OUTSIDE JEB Source Type: research

No oxygen? No mitochondria? No problem [OUTSIDE JEB]
Oana Birceanu (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Birceanu, O. Tags: OUTSIDE JEB Source Type: research

Temperature spikes snuff out Earth's biodiversity [OUTSIDE JEB]
Erin McCallum (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: McCallum, E. Tags: OUTSIDE JEB Source Type: research

Sex-specific molecular specialization and activity rhythm dependent gene expression in honey bee antennae [RESEARCH ARTICLE]
Rikesh Jain and Axel Brockmann We performed an RNA-seq based comparison of gene expression levels in the antennae of honey bee drones and time-trained foragers (workers) collected at different times of the day and different activity states. Interestingly, olfaction-related genes (i.e. odorant receptor (Ors), odorant binding proteins (Obps), carboxyl esterases (CEst) etc.) showed stable gene expression differences between drone and worker antennae. Drone antennae showed higher expression of 24 Ors, of which 21 belong to the clade X which comprises the receptor for the major queen pheromone compound 9-ODA. This high number o...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Jain, R., Brockmann, A. Tags: RESEARCH ARTICLE Source Type: research

The role of the gut microbiome in mediating standard metabolic rate after dietary shifts in the viviparous cockroach, Diploptera punctata [RESEARCH ARTICLE]
Paul A. Ayayee, George Kinney, Chris Yarnes, Thomas Larsen, Gordon F. Custer, Linda T. A. van Diepen, and Agusti Munoz-Garcia Diet may be a significant determinant of insect gut microbiome composition. However, the extent to which dietary shifts shape both the composition and relevant functions of insect gut microbiomes, and ultimately, impact host energy balance (i.e., metabolic phenotype) is not well understood. We investigated the impacts of diet switching on Diploptera punctata females maintained on dog food (DF) diet relative to those fed a comparatively sub-optimal cellulose-amended dog food (CADF) diet for four week...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Ayayee, P. A., Kinney, G., Yarnes, C., Larsen, T., Custer, G. F., van Diepen, L. T. A., Munoz-Garcia, A. Tags: RESEARCH ARTICLE Source Type: research

Vitellogenin offsets oxidative costs of reproduction in female painted dragon lizards [RESEARCH ARTICLE]
In conclusion, VTG may be under selection to offset oxidative costs of reproduction in egg-producing species. (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Lindsay, W. R., Friesen, C. R., Sihlbom, C., Bergström, J., Berger, E., Wilson, M. R., Olsson, M. Tags: RESEARCH ARTICLE Source Type: research

Stable mitochondrial CICIII2 supercomplex interactions in reptiles compared to homeothermic vertebrates [RESEARCH ARTICLE]
Amanda Bundgaard, Andrew M. James, Michael E. Harbour, Michael P. Murphy, and Angela Fago The association of complex I (CI), complex III (CIII) and complex IV (CIV) of the mitochondrial electron transport chain into stable high-molecular weight supercomplexes (SCs) has been observed in several prokaryotes and eukaryotes, but among vertebrates it has only been examined in mammals. The biological role of these SCs is unclear but suggestions so far include enhanced electron transfer between complexes, decreased production of the reactive oxygen species (ROS) O2·– and H2O2, or enhanced structural stability. Here, ...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Bundgaard, A., James, A. M., Harbour, M. E., Murphy, M. P., Fago, A. Tags: RESEARCH ARTICLE Source Type: research

Impairment of mixed melanin-based pigmentation in parrots [RESEARCH ARTICLE]
Ana Carolina de Oliveira Neves, Ismael Galvan, and Dirk Van den Abeele Parrots and allies (Order Psittaciformes) have evolved an exclusive capacity to synthesize polyene pigments called psittacofulvins at feather follicles, which allows them to produce a striking diversity of pigmentation phenotypes. Melanins are polymers constituting the most abundant pigments in animals, and the sulphurated form (pheomelanin) produces colors that are similar to those produced by psittacofulvins. However, the differential contribution of these pigments to psittaciform phenotypic diversity has not been investigated. Given the color redunda...
Source: Journal of Experimental Biology - May 11, 2020 Category: Biology Authors: Neves, A. C. d. O., Galvan, I., Van den Abeele, D. Tags: RESEARCH ARTICLE Source Type: research

Two percent change switches motor muscle to brake [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - May 7, 2020 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Exposure to hot temperatures during lactation in Swiss mice stunts offspring growth and decreases future reproductive performance of female offspring [RESEARCH ARTICLE]
In this study, F1 mice weaned from mothers lactating at 21 and 32.5°C were housed at 21°C from day 19 until day 56 of age, during which food intake and body mass were measured. The F1 adult females that were weaned at the two temperatures were bred and then exposed to 32.5°C during lactation. Energy intake and milk output, and litter size and mass, were determined. The F1 adults weaned at 32.5°C consumed less food and had lower body mass than their counterparts weaned at 21°C. Several visceral organs or reproductive tissues were significantly lower in mass in F1 weaned at 32.5°C than at 21...
Source: Journal of Experimental Biology - May 7, 2020 Category: Biology Authors: Bao, M.-H., Chen, L.-B., Hambly, C., Speakman, J. R., Zhao, Z.-J. Tags: RESEARCH ARTICLE Source Type: research

Individual vocal recognition in zebra finches relies on song syllable structure rather than song syllable order [RESEARCH ARTICLE]
Nicole Geberzahn and Sebastien Deregnaucourt Many species are able to vocally recognize individual conspecifics and this capacity seems widespread in oscine songbirds. The exact acoustic features used for such recognition are often not clear. In the zebra finch (Taeniopygia guttata), the song motif is composed of a few syllables repeated in a fixed sequential order and song bouts include several repetitions of the motif. Here, we used an operant discrimination task, the GO/NOGO procedure, to show that zebra finches are capable of individual vocal recognition even if the bird has to distinguish males that all produce an im...
Source: Journal of Experimental Biology - May 7, 2020 Category: Biology Authors: Geberzahn, N., Deregnaucourt, S. Tags: RESEARCH ARTICLE Source Type: research

Using aerobic exercise to evaluate sub-lethal tolerance of acute warming in fishes [RESEARCH ARTICLE]
Felipe R. Blasco, Andrew J. Esbaugh, Shaun S. Killen, Francisco Tadeu Rantin, Edwin W. Taylor, and David J. McKenzie We investigated whether fatigue from sustained aerobic swimming provides a sub-lethal endpoint to define tolerance of acute warming in fishes, as an alternative to loss of equilibrium (LOE) during a critical thermal maximum (CTmax) protocol. Two species were studied, Nile tilapia (Oreochromis niloticus) and pacu (Piaractus mesopotamicus). Each fish underwent an incremental swim test to determine gait transition speed (UGT), where it first engaged the unsteady anaerobic swimming mode that preceded fatigue. A...
Source: Journal of Experimental Biology - May 7, 2020 Category: Biology Authors: Blasco, F. R., Esbaugh, A. J., Killen, S. S., Rantin, F. T., Taylor, E. W., McKenzie, D. J. Tags: RESEARCH ARTICLE Source Type: research

Variable occurrence of apoptosis in the testes of diploid and sterile allotetraploid Cobitis (Teleostei, Cobitidae) males during the reproductive cycle [SHORT COMMUNICATION]
Olga Jablonska, Dorota Juchno, Anna Leska, Karolina Kowalewska, and Alicja Boron Cobitis species exist in both diploid and diploid–polyploid (d–p) populations, but mostly occur in the latter. They are considered an important model organism to study the biology and physiology of natural hybrid and polyploid vertebrates. Indeed, polyploidization causes a huge stress for in terms of cell physiology and alters spermatogenesis in polyploid fish. The most extensively studied mode of germ cell death during spermatogenesis in vertebrates is apoptosis. The aim of this study was to examine caspase-3 immunoexpression in ...
Source: Journal of Experimental Biology - May 7, 2020 Category: Biology Authors: Jablonska, O., Juchno, D., Leska, A., Kowalewska, K., Boron, A. Tags: SHORT COMMUNICATION Source Type: research