Transforming growth factor-beta 1 (TGF-{beta}1) induces the differentiation of rainbow trout (Oncorhynchus mykiss) cardiac fibroblasts into myofibroblasts [RESEARCH ARTICLE]
Elizabeth F. Johnston and Todd E. Gillis The collagen content of the rainbow trout heart increases in response to cold acclimation, and decreases with warm acclimation. This ability to remodel the myocardial extracellular matrix (ECM) makes these fish useful models to study the cellular pathways involved in collagen regulation in the vertebrate heart. Remodeling of the ECM in the mammalian heart is regulated, in part, by myofibroblasts which arise from pre-existing fibroblasts in response to transforming growth factor-beta 1 (TGF-β1). We have previously demonstrated that treatment of cultured rainbow trout cardiac fib...
Source: Journal of Experimental Biology - November 5, 2018 Category: Biology Authors: Johnston, E. F., Gillis, T. E. Tags: RESEARCH ARTICLE Source Type: research

The role of parasitism in the energy management of a free-ranging bird [RESEARCH ARTICLE]
Olivia Hicks, Sarah J. Burthe, Francis Daunt, Mark Newell, Olivier Chastel, Charline Parenteau, and Jonathan A. Green Parasites often prompt sub-lethal costs to the host by eliciting immune responses. These costs can be hard to quantify but are crucial to our understanding of their host's ecology. Energy is a fundamental currency to quantify these costs, as energetic trade-offs often exist between key fitness-related processes. Daily energy expenditure (DEE) comprises of resting metabolic rate (RMR) and energy available for activity which are linked via the energy management strategy of an organism. Parasitism may play a r...
Source: Journal of Experimental Biology - November 5, 2018 Category: Biology Authors: Hicks, O., Burthe, S. J., Daunt, F., Newell, M., Chastel, O., Parenteau, C., Green, J. A. Tags: RESEARCH ARTICLE Source Type: research

Deletion of a specific exon in the voltage-gated calcium channel, cacophony, causes disrupted locomotion in Drosophila larvae [RESEARCH ARTICLE]
Kayly M. Lembke, Alexander D. Law, Jasmine Ahrar, and David B. Morton Tar DNA binding protein 43 (TDP-43) is an RNA binding protein that regulates transcription, translation, and alternative splicing of mRNA. We have shown previously that null mutations of the Drosophila orthologue, Tar DNA-binding homologue (tbph), causes severe locomotion defects in larvae that are mediated by a reduction in the expression of the type II voltage-gated calcium channel, cacophony (cac). We also showed that TDP-43 regulates the inclusion of alternatively spliced exons of cacophony; tbph mutants showed significantly increased expression of c...
Source: Journal of Experimental Biology - November 5, 2018 Category: Biology Authors: Lembke, K. M., Law, A. D., Ahrar, J., Morton, D. B. Tags: RESEARCH ARTICLE Source Type: research

Electrical interactions between photoreceptors in the compound eye of Periplaneta americana [RESEARCH ARTICLE]
Paulus Saari, Esa-Ville Immonen, Andrew S. French, Päivi H. Torkkeli, Hongxia Liu, Kyösti Heimonen, and Roman V. Frolov The compound eye of Periplaneta americana contains two spectral classes of photoreceptors: narrow-band UV-sensitive and broad-band green-sensitive. In intracellular recordings, stimulation of green-sensitive photoreceptors with flashes of relatively bright UV/violet light produced anomalous delayed depolarization after the end of the normal light response, whereas stimulation of UV-sensitive photoreceptors with green light elicited biphasic responses characterized by initial transient hyperpolarizati...
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Saari, P., Immonen, E.-V., French, A. S., Torkkeli, P. H., Liu, H., Heimonen, K., Frolov, R. V. Tags: RESEARCH ARTICLE Source Type: research

Widespread 'gassing off in killifishes [OUTSIDE JEB]
Brittney G. Borowiec (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Borowiec, B. G. Tags: OUTSIDE JEB Source Type: research

Enemy at the bat cave door [OUTSIDE JEB]
Oana Birceanu (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Birceanu, O. Tags: OUTSIDE JEB Source Type: research

Caution! A firefly approaches... [OUTSIDE JEB]
Erin McCallum (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: McCallum, E. Tags: OUTSIDE JEB Source Type: research

Hibernating squirrels tweak sodium channels to rest their brain [OUTSIDE JEB]
Daniel M. Vahaba (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Vahaba, D. M. Tags: OUTSIDE JEB Source Type: research

Eating poop makes naked mole-rats motherly [OUTSIDE JEB]
Daniel E. Rozen (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Rozen, D. E. Tags: OUTSIDE JEB Source Type: research

Temperature and dehydration effects on metabolism, water uptake, and the partitioning between respiratory and cutaneous evaporative water loss in a terrestrial toad [RESEARCH ARTICLE]
Luis Miguel Senzano and Denis Vieira Andrade Terrestrial anurans often experience fluctuations in body temperature and hydration state, which are known to influence evaporative water loss through the skin (EWLSkin) and lungs (EWLResp). These effects arises from associated changes in skin permeability, metabolism and lung ventilation. Herein, we determined the rates of EWLSkin and EWLResp in the terrestrial toad, Rhinella schneideri, at different temperatures and hydration states. We measured oxygen uptake rates to verify whether alterations in the partitioning between EWLSkin and EWLResp were associated to metabolic induce...
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Senzano, L. M., Andrade, D. V. Tags: RESEARCH ARTICLE Source Type: research

Underlying mechanisms and ecological context of variation in exploratory behavior of the Argentine ant, Linepithema humile [RESEARCH ARTICLE]
Hannah Page, Andrew Sweeney, Anna Pilko, and Noa Pinter-Wollman Uncovering how and why animals explore their environment is fundamental for understanding population dynamics, the spread of invasive species, species interactions etc. In social animals, individuals within a group can vary in their exploratory behavior and the behavioral composition of the group can determine its collective success. Workers of the invasive Argentine ant (Linepithema humile) exhibit individual variation in exploratory behavior, which affects the colony's collective nest selection behavior. Here we examine the mechanisms underlying this behavio...
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Page, H., Sweeney, A., Pilko, A., Pinter-Wollman, N. Tags: RESEARCH ARTICLE Source Type: research

Diapause-associated changes in the lipid and metabolite profile of the Asian tiger mosquito, Aedes albopictus [RESEARCH ARTICLE]
Zachary A. Batz and Peter A. Armbruster Diapause is an alternative life-history strategy that allows organisms to enter developmental arrest in anticipation of unfavorable conditions. Diapause is widespread among insects and plays a key role in enhancing overwinter survival as well as defining the seasonal and geographic distributions of populations. Next generation sequencing has greatly advanced our understanding of the transcriptional basis for this crucial adaptation but less is known about regulation of embryonic diapause physiology at the metabolite level. Here, we characterized the lipid and metabolite profile of em...
Source: Journal of Experimental Biology - November 1, 2018 Category: Biology Authors: Batz, Z. A., Armbruster, P. A. Tags: RESEARCH ARTICLE Source Type: research

Super freezing larvae survive despite incurred damage [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Insect fat body cell morphology and response to cold stress is modulated by acclimation [RESEARCH ARTICLE]
Lauren E. Des Marteaux, Tomas Stetina, and Vladimir Kostal Mechanistic understanding about the nature of cellular cryoinjury and mechanisms by which some animals survive freezing while others do not is currently lacking. Here, we exploited the broadly manipulable freeze tolerance of larval malt flies (Chymomyza costata) to uncover cell and tissue morphological changes associated with freeze mortality. Diapause induction, cold acclimation and dietary proline supplementation generate malt fly variants ranging from weakly to extremely freeze tolerant. Using confocal microscopy and immunostaining of the fat body, Malpighian t...
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Des Marteaux, L. E., Stetina, T., Kostal, V. Tags: Ecophysiology: responses to environmental stressors and change RESEARCH ARTICLE Source Type: research

Controlled feeding experiments with diets of different abrasiveness reveal slow development of mesowear signal in goats (Capra aegagrus hircus) [RESEARCH ARTICLE]
Nicole L. Ackermans, Daniela E. Winkler, Ellen Schulz-Kornas, Thomas M. Kaiser, Dennis W. H. Müller, Patrick R. Kircher, Jürgen Hummel, Marcus Clauss, and Jean-Michel Hatt Dental mesowear is applied as a proxy to determine the general diet of mammalian herbivores based on tooth-cusp shape and occlusal relief. Low, blunt cusps are considered typical of grazers and high, sharp cusps typical of browsers. However, how internal or external abrasives impact mesowear, and the time frame the wear signature takes to develop, still need to be explored. Four different pelleted diets of increasing abrasiveness (lucerne, grass, gr...
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Ackermans, N. L., Winkler, D. E., Schulz-Kornas, E., Kaiser, T. M., Müller, D. W. H., Kircher, P. R., Hummel, J., Clauss, M., Hatt, J.-M. Tags: RESEARCH ARTICLE Source Type: research

Aerobic capacities and swimming performance of polar cod (Boreogadus saida) under ocean acidification and warming conditions [RESEARCH ARTICLE]
This study aimed to investigate the influence of ocean acidification and warming on maximum performance parameters of B. saida as indicators for the species' acclimation capacities under environmental conditions projected for the end of this century. After 4 months at four acclimation temperatures (0, 3, 6, 8°C) each combined with two PCO2 levels (390 and 1170 µatm), aerobic capacities and swimming performance of B. saida were recorded following a Ucrit protocol. At both CO2 levels, standard metabolic rate (SMR) was elevated at the highest acclimation temperature indicating thermal limitations. Max...
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Kunz, K. L., Claireaux, G., Pörtner, H.-O., Knust, R., Mark, F. C. Tags: Ecophysiology: responses to environmental stressors and change RESEARCH ARTICLE Source Type: research

Limits to sustained energy intake. XXIX. The case of the golden hamster (Mesocricetus auratus) [RESEARCH ARTICLE]
Sarah A. Ohrnberger, Catherine Hambly, John R. Speakman, and Teresa G. Valencak Golden hamster females have the shortest known gestation period among placental mammals, and at the same time raise very large litters of up to 16 offspring, which are born in a naked and blind state and are only able to pick up food from days 12 to 14 onwards. We quantified energy metabolism and milk production in female golden hamsters raising offspring under cold (8°C), normal (22°C) and hot (30°C) ambient temperature conditions. We monitored energy intake, subcutaneous body temperature, daily energy expenditure, litter size and...
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Ohrnberger, S. A., Hambly, C., Speakman, J. R., Valencak, T. G. Tags: RESEARCH ARTICLE Source Type: research

Optomotor steering and flight control requires a specific sub-section of the compound eye in the hawkmoth, Manduca sexta [RESEARCH ARTICLE]
Sean Copley, Kalyanasundaram Parthasarathy, and Mark A. Willis While tracking odor plumes, male hawkmoths use optic flow cues to stabilize their flight movements with respect to their environment. We studied the responses of freely flying moths tracking odor plumes in a laboratory wind tunnel and tethered moths in an optomotor flight simulator to determine the locations on the compound eye on which critical optic flow cues are detected. In these behavioral experiments, we occluded specific regions of the compound eye and systematically examined the moths' behavior for specific deficits in optic flow processing. Freely fly...
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Copley, S., Parthasarathy, K., Willis, M. A. Tags: Neuroethology RESEARCH ARTICLE Source Type: research

Deciphering VO2,max: limits of the genetic approach [COMMENTARY]
Hans Hoppeler Maximal oxygen consumption (VO2,max) denotes the upper limit of aerobic energy flux through the cascade of oxygen transfer from the environment to tissue mitochondria, essentially to skeletal muscle mitochondria during intense exercise. A high VO2,max is a key component for athletic success in human and animal endurance sports. From a public health perspective, a high VO2,max is a validated negative predictor for cardiovascular disease and all-cause mortality. VO2,max varies by more than twofold between sedentary subjects and shows a heritability value greater than 50%. Likewise, the capacity for an individu...
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Hoppeler, H. Tags: COMMENTARY Source Type: research

Can variation among hypoxic environments explain why different fish species use different hypoxic survival strategies? [REVIEW]
Milica Mandic and Matthew D. Regan In aquatic environments, hypoxia is a multi-dimensional stressor that can vary in O2 level (partial pressure of O2 in water, PwO2), rate of induction and duration. Natural hypoxic environments can therefore be very different from one another. For the many fish species that have evolved to cope with these different hypoxic environments, survival requires adjusting energy supply and demand pathways to maintain energy balance. The literature describes innumerable ways that fishes combine aerobic metabolism, anaerobic metabolism and metabolic rate depression (MRD) to accomplish this, but it ...
Source: Journal of Experimental Biology - October 31, 2018 Category: Biology Authors: Mandic, M., Regan, M. D. Tags: REVIEW Source Type: research

Listening antlions drop to evade dining bats [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Ultrasound avoidance by flying antlions (Myrmeleontidae) [RESEARCH ARTICLE]
Marc W. Holderied, Liam A. Thomas, and Carmi Korine The acoustic arms race between insectivorous bats and their invertebrate prey has led to the convergent evolution of ultrasound hearing in seven orders of nocturnal insects. Upon hearing the echolocation calls of an approaching bat, such insects take defensive action. Here, we document a previously unknown sense of ultrasound hearing and phonotactic flight behaviour in the neuropteran family Myrmeleontidae (antlions). The antlion Myrmeleon hyalinus was presented with sound pulses at ultrasonic frequencies used by echolocating bats and its response thresholds in tethered ...
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Holderied, M. W., Thomas, L. A., Korine, C. Tags: RESEARCH ARTICLE Source Type: research

No short-term physiological costs of offspring care in a cooperatively breeding bird [RESEARCH ARTICLE]
Sarah Guindre-Parker and Dustin R. Rubenstein The cost of reproduction results in a life-history trade-off where investment in current reproduction via costly parental care decreases subsequent fitness. Although this trade-off is thought to occur ubiquitously across animals, there is equivocal evidence that parental care behaviours are costly. A major challenge of studying the cost of parental care has been a lack of consensus over which physiological mechanisms underlie this trade-off. Here, we compare four traits believed to mediate the cost of parental care by examining whether glucocorticoids, oxidative stress, immune...
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Guindre-Parker, S., Rubenstein, D. R. Tags: RESEARCH ARTICLE Source Type: research

How temperature influences the viscosity of hornworm hemolymph [RESEARCH ARTICLE]
Melissa C. Kenny, Matthew N. Giarra, Ellen Granata, and John J. Socha Hemolymph is responsible for the transport of nutrients and metabolic waste within the insect circulatory system. Circulation of hemolymph is governed by viscosity, a physical property, which is well known to be influenced by temperature. However, the effect of temperature on hemolymph viscosity is unknown. We used Manduca sexta larvae to measure hemolymph viscosity across a range of physiologically relevant temperatures. Measurements were taken from 0 to 45°C using a cone and plate viscometer in a sealed environmental chamber. Hemolymph viscosity d...
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Kenny, M. C., Giarra, M. N., Granata, E., Socha, J. J. Tags: RESEARCH ARTICLE Source Type: research

Aquatic versus terrestrial crab skeletal support: morphology, mechanics, molting and scaling [RESEARCH ARTICLE]
Jennifer R. A. Taylor The transition from aquatic to terrestrial environments places significant mechanical challenges on skeletal support systems. Crabs have made this transition multiple times and are the largest arthropods to inhabit both environments. Furthermore, they alternate between rigid and hydrostatic skeletons, making them an interesting system to examine mechanical adaptations in skeletal support systems. I hypothesized that terrestrial crabs have modified morphology to enhance mechanical stiffness and that rigid and hydrostatic skeletons scale differently from each other, with stronger allometric relationshi...
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Taylor, J. R. A. Tags: RESEARCH ARTICLE Source Type: research

Physiological responses of ionotropic histamine receptors, PxHCLA and PxHCLB, to neurotransmitter candidates in a butterfly, Papilio xuthus [RESEARCH ARTICLE]
Hiroshi D. Akashi, Pei-Ju Chen, Tokiho Akiyama, Yohey Terai, Motohiro Wakakuwa, Yasunori Takayama, Makoto Tominaga, and Kentaro Arikawa Histamine is the only known neurotransmitter released by arthropod photoreceptors. Synaptic transmission from photoreceptors to second-order neurons is mediated by the activation of histamine-gated chloride channels (HCLs). These histaminergic synapses have been assumed to be conserved among insect visual systems. However, our understanding of the channels in question has thus far been based on studies in flies. In the butterfly Papilio xuthus, we have identified two candidate histamine-g...
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Akashi, H. D., Chen, P.-J., Akiyama, T., Terai, Y., Wakakuwa, M., Takayama, Y., Tominaga, M., Arikawa, K. Tags: RESEARCH ARTICLE Source Type: research

Comparing the impacts of macronutrients on life-history traits in larval and adult Drosophila melanogaster: the use of nutritional geometry and chemically defined diets [RESEARCH ARTICLE]
Taehwan Jang and Kwang Pum Lee Protein and carbohydrate are the two major macronutrients that exert profound influences over fitness in many organisms, including Drosophila melanogaster. Our understanding of how these macronutrients shape the components of fitness in D. melanogaster has been greatly enhanced by the use of nutritional geometry, but most nutritional geometric analyses on this species have been conducted using semi-synthetic diets that are not chemically well defined. Here, we combined the use of nutritional geometry and chemically defined diets to compare the patterns of larval and adult life-history traits...
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Jang, T., Lee, K. P. Tags: RESEARCH ARTICLE Source Type: research

Head width influences flow sensing by the lateral line canal system in fishes [RESEARCH ARTICLE]
In this study, we explored how head width, a trait that can vary greatly between species and across ontogeny, affects flow sensing. We inserted pressure sensors into physical fish head models of varying widths (narrow, intermediate and wide) and placed these models in steady and vortical flows. We measured sensory performance in terms of detecting flow parameters (flow speed, vortex shedding frequency and cylinder diameter), sensitivity (change in pressure gradient as a function of flow speed) and signal-to-noise ratio (SNR; strength of vortex shedding frequency with respect to background). Our results show that in all mod...
Source: Journal of Experimental Biology - October 29, 2018 Category: Biology Authors: Yanagitsuru, Y. R., Akanyeti, O., Liao, J. C. Tags: RESEARCH ARTICLE Source Type: research

Forelimb position affects facultative bipedal locomotion in lizards [RESEARCH ARTICLE]
This study quantified the frequency of bipedalism when sprinting with vs. without an obstacle at 0.8 meters from initiating a sprint. Forelimb positions were quantified during bipedal running at the start of a sprint and when crossing an obstacle. Two species with contrasting body forms (and thus different body center of mass; BCoM) were studied (Sceloporus woodi, Aspidoscelis sexlineata) to assess potential variation due to body plan and obstacle crossing behavior. No significant difference in frequency of bipedalism was observed in S. woodi with or without an obstacle. However, A. sexlineata primarily used a bipedal post...
Source: Journal of Experimental Biology - October 26, 2018 Category: Biology Authors: Kinsey, C. T., McBrayer, L. D. Tags: RESEARCH ARTICLE Source Type: research

Diet and ambient temperature interact to shape plasma fatty acid composition, basal metabolic rate, and oxidative stress in great tits [RESEARCH ARTICLE]
Martin N. Andersson, Johan Nilsson, Jan-Ake Nilsson, and Caroline Isaksson Diet and ambient temperature affect animal physiology, survival and reproductive success. However, knowledge of how these environmental factors interact to shape physiological processes and life-history traits of birds and other animals is largely lacking. By exposing adult great tits (Parus major) to two contrasting diets (saturated or unsaturated fatty acids; SFA and UFA, respectively) and ambient temperatures (3°C versus 20°C) that the birds encounter in nature, we investigated the effects of these two factors on several physiological par...
Source: Journal of Experimental Biology - October 25, 2018 Category: Biology Authors: Andersson, M. N., Nilsson, J., Nilsson, J.-A., Isaksson, C. Tags: RESEARCH ARTICLE Source Type: research

The choreography of learning walks in the Australian jack jumper ant Myrmecia croslandi [RESEARCH ARTICLE]
Piyankarie Jayatilaka, Trevor Murray, Ajay Narendra, and Jochen Zeil We provide a detailed analysis of the learning walks performed by Myrmecia croslandi ants at the nest during which they acquire visual information on its location. Most learning walks of 12 individually marked naïve ants took place in the morning with a narrow time window separating the first two learning walks, which most often occurred on the same day. Naïve ants performed between two and seven walks over up to four consecutive days before heading out to forage. On subsequent walks, naïve ants tend to explore the area around the nest in new compa...
Source: Journal of Experimental Biology - October 24, 2018 Category: Biology Authors: Jayatilaka, P., Murray, T., Narendra, A., Zeil, J. Tags: Neuroethology RESEARCH ARTICLE Source Type: research

Sperm pre-fertilization thermal environment shapes offspring phenotype and performance [RESEARCH ARTICLE]
Jukka Kekäläinen, Parastu Oskoei, Matti Janhunen, Heikki Koskinen, Raine Kortet, and Hannu Huuskonen The sperm pre-fertilization environment has recently been suggested to mediate remarkable transgenerational consequences for offspring phenotype (transgenerational plasticity, TGB), but the adaptive significance of the process has remained unclear. Here, we studied the transgenerational effects of sperm pre-fertilization thermal environment in a cold-adapted salmonid, the European whitefish (Coregonus lavaretus). We used a full-factorial breeding design where the eggs of five females were fertilized with the milt of 10...
Source: Journal of Experimental Biology - October 24, 2018 Category: Biology Authors: Kekäläinen, J., Oskoei, P., Janhunen, M., Koskinen, H., Kortet, R., Huuskonen, H. Tags: Ecophysiology: responses to environmental stressors and change RESEARCH ARTICLE Source Type: research

Echo interval and not echo intensity drives bat flight behavior in structured corridors [RESEARCH ARTICLE]
Michaela Warnecke, Silvio Macias, Benjamin Falk, and Cynthia F. Moss To navigate in the natural environment, animals must adapt their locomotion in response to environmental stimuli. The echolocating bat relies on auditory processing of echo returns to represent its surroundings. Recent studies have shown that echo flow patterns influence bat navigation, but the acoustic basis for flight path selection remains unknown. To investigate this problem, we released bats in a flight corridor with walls constructed of adjacent individual wooden poles, which returned cascades of echoes to the flying bat. We manipulated the spacing ...
Source: Journal of Experimental Biology - October 24, 2018 Category: Biology Authors: Warnecke, M., Macias, S., Falk, B., Moss, C. F. Tags: RESEARCH ARTICLE Source Type: research

Ascending flight and decelerating vertical glides in Anna's hummingbirds [RESEARCH ARTICLE]
Victor Manuel Ortega-Jimenez and Robert Dudley Hummingbirds are observationally well known for their capacity to vertically ascend whilst hovering, but the underlying mechanics and possible energetic limits to ascent rates are unclear. Decelerations during vertical ascent to a fixed target may also be associated with specific visual responses to regulate the body's trajectory. Here, we studied climbing flight and subsequent deceleration in male Anna's hummingbirds (Calypte anna) over an approximately two meter vertical distance. Birds reached vertical speeds and accelerations up to ~4 m/s and 10 m/s2, respectively, through...
Source: Journal of Experimental Biology - October 24, 2018 Category: Biology Authors: Ortega-Jimenez, V. M., Dudley, R. Tags: RESEARCH ARTICLE Source Type: research

Sleep regulates visual selective attention in Drosophila [RESEARCH ARTICLE]
Leonie Kirszenblat, Deniz Ertekin, Joseph Goodsell, Yanqiong Zhou, Paul J. Shaw, and Bruno van Swinderen Although sleep deprivation is known to impair attention in humans and other mammals, the underlying reasons are not well understood, and whether similar effects are present in non-mammalian species is not known. We therefore sought to investigate whether sleep is important for optimizing attention in an invertebrate species, the genetic model Drosophila melanogaster. We developed a high-throughput paradigm to measure visual attention in freely-walking Drosophila, using competing foreground/background visual stimuli. We ...
Source: Journal of Experimental Biology - October 24, 2018 Category: Biology Authors: Kirszenblat, L., Ertekin, D., Goodsell, J., Zhou, Y., Shaw, P. J., van Swinderen, B. Tags: RESEARCH ARTICLE Source Type: research

Food dissemination in ants: Robustness of the trophallactic network against resource quality [SHORT COMMUNICATION]
Olivier Bles, Jean-Louis Deneubourg, and Stamatios C. Nicolis Insect societies are often composed of many individuals, achieving collective decisions that depend on environmental and colonial characteristics. For example, ants are able to focus their foraging effort on the most rewarding food source. While this phenomenon is well known, the link between the food source quality and the intranidal food dissemination networks and its dynamics has been neglected. Here we analysed the global dynamics of the food dissemination in Camponotus cruentatus workers, after feeding on a low (0.1M) or on a high (1M) sucrose concentration...
Source: Journal of Experimental Biology - October 24, 2018 Category: Biology Authors: Bles, O., Deneubourg, J.-L., Nicolis, S. C. Tags: SHORT COMMUNICATION Source Type: research

Rh protein is key for crab waste disposal [INSIDE JEB]
Kathryn Knight (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Knight, K. Tags: INSIDE JEB Source Type: research

Identification of the role of Rh protein in ammonia excretion of the swimming crab Portunus trituberculatus [RESEARCH ARTICLE]
Lingjun Si, Luqing Pan, Hongdan Wang, and Xin Zhang In Portunus trituberculatus, a full-length cDNA of Rhesus-like glycoprotein (Rh protein), encoding the entire 478 amino acid protein, has been identified in gills, and plays an essential role in ammonia (NH3/NH4+) excretion. Phylogenetic analysis of Rh-like proteins from crabs was clustered, showing high conservation of the ammonium transporter domain and transmembrane segments essential to the function of Rh protein. Rh protein of P. trituberculatus (PtRh) was detected in all tested tissues, and showed the highest expression in the gills. To further characterize the rol...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Si, L., Pan, L., Wang, H., Zhang, X. Tags: RESEARCH ARTICLE Source Type: research

Bite force and cranial bone strain in four species of lizards [RESEARCH ARTICLE]
Callum F. Ross, Laura B. Porro, Anthony Herrel, Susan E. Evans, and Michael J. Fagan In vivo bone strain data provide direct evidence of strain patterns in the cranium during biting. Compared to mammals, in vivo bone strains in lizard skulls are poorly documented. This paper presents strain data from the skulls of Anolis equestris, Gekko gecko, Iguana iguana and Salvator merianae during transducer biting. Analysis of variance was used to investigate effects of bite force, bite point, diet, cranial morphology and cranial kinesis on strain magnitudes. Within individuals the most consistent determinants of variance in bone st...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Ross, C. F., Porro, L. B., Herrel, A., Evans, S. E., Fagan, M. J. Tags: RESEARCH ARTICLE Source Type: research

Altered thermoregulation as a driver of host behaviour in glochidia-parasitised fish [RESEARCH ARTICLE]
Pavel Horky, Ondrej Slavik, and Karel Douda Parasites alter their host behaviour and vice versa as a result of mutual adaptations in the evolutionary arms race. One of these adaptations involves changes in host thermoregulation, which has the potential to harm the parasite and thereby act as a defence mechanism. We used a model of the brown trout Salmo trutta experimentally parasitised with ectoparasitic larvae called glochidia from the endangered freshwater pearl mussel Margaritifera margaritifera to reveal whether parasitation alters fish behavioural thermoregulation. A study based on radio telemetry temperature sensors ...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Horky, P., Slavik, O., Douda, K. Tags: RESEARCH ARTICLE Source Type: research

An attempt to select non-genetic variation in resistance to starvation and reduced chill coma recovery time in Drosophila melanogaster [RESEARCH ARTICLE]
Bianca F. Menezes, Judit Salces-Ortiz, Heloïse Muller, Nelly Burlet, Sonia Martinez, Marie Fablet, and Cristina Vieira Phenotypic variance is attributed to genetic and non-genetic factors, and only the former are supposed to be inherited and thus suitable for the action of selection. Although increasing amounts of data suggest that non-genetic variability may be inherited, we have limited empirical data in animals. Here, we performed an artificial selection experiment using Drosophila melanogaster inbred lines. We quantified the response to selection for a decrease in chill coma recovery time and an increase in starvatio...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Menezes, B. F., Salces-Ortiz, J., Muller, H., Burlet, N., Martinez, S., Fablet, M., Vieira, C. Tags: RESEARCH ARTICLE Source Type: research

Subspecies differences in thermal acclimation of mitochondrial function and the role of uncoupling proteins in killifish [RESEARCH ARTICLE]
Heather J. Bryant, Dillon J. Chung, and Patricia M. Schulte Thermal effects on mitochondrial efficiency and ATP production can influence whole-animal thermal tolerance and performance. Thus, organisms may have the capacity to alter mitochondrial processes through acclimation or adaptation to mitigate these effects. One possible mechanism is through the action of uncoupling proteins (UCPs) which can decrease the proton motive force independent of the production of ATP. To test this hypothesis, we examined the mRNA expression patterns of UCP isoforms and characterized the effects of thermal acclimation and putative local the...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Bryant, H. J., Chung, D. J., Schulte, P. M. Tags: RESEARCH ARTICLE Source Type: research

Flight energetics, caste dimorphism and scaling properties in the bumblebee Bombus impatiens [RESEARCH ARTICLE]
Fannie Billardon and Charles-A. Darveau Animal size affects energetics of locomotion. Using female caste dimorphism in bumblebees, we assessed how body mass impacted morphological and physiological traits linked with flight. The allometric relationships obtained for workers wing surface area, wingbeat frequency, flight and resting metabolic rates could predict the trait values of queens that are more than four-fold larger. Flight success of queens decreased over time in part due to a large increase in body mass, and decrease in traits linked with flight, namely wingbeat frequency, metabolic rate, and the activity of metabo...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Billardon, F., Darveau, C.-A. Tags: RESEARCH ARTICLE Source Type: research

Interactions between corticosterone phenotype, environmental stressor pervasiveness and irruptive movement-related survival [RESEARCH ARTICLE]
Tim S. Jessop, Jonathan Webb, Tim Dempster, Benjamin Feit, and Mike Letnic Animals use irruptive movement to avoid exposure to stochastic and pervasive environmental stressors that impact fitness. Beneficial irruptive movements transfer individuals from high-stress areas (conferring low fitness) to alternate localities that may improve survival or reproduction. However, being stochastic, environmental stressors can limit an animal's preparatory capacity to enhance irruptive movement performance. Thus individuals must rely on standing, or rapidly induced, physiological and behavioural responses. Rapid elevation of glucocort...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Jessop, T. S., Webb, J., Dempster, T., Feit, B., Letnic, M. Tags: RESEARCH ARTICLE Source Type: research

Mechanical behavior of shark vertebral centra at biologically relevant strains [RESEARCH ARTICLE]
D. I. Ingle, L. J. Natanson, and M. E. Porter Cartilaginous shark skeletons experience axial deformation at the intervertebral joints, but also within the mineralized cartilaginous centrum, which can compress to between 3 - 8% of its original length in a free-swimming shark. Previous studies have focused on shark centra mechanical properties when loaded to failure, and our goal was to determine properties when compressed to a biologically relevant strain. We selected vertebrae from six shark species and from the anterior and posterior regions of the vertebral column. Centra were x-radiographed to measure double cone propor...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Ingle, D. I., Natanson, L. J., Porter, M. E. Tags: RESEARCH ARTICLE Source Type: research

Scaling of claw sharpness: mechanical constraints reduce attachment performance in larger insects [RESEARCH ARTICLE]
Jonathan G. Pattrick, David Labonte, and Walter Federle Claws are the most widespread attachment devices in animals, but comparatively little is known about the mechanics of claw attachment. A key morphological parameter in determining attachment ability is claw sharpness; however, there is a conflict between sharpness and fracture resistance. Sharper claws can interlock on more surfaces but are more likely to break. Body size interacts with this conflict such that larger animals should have much blunter claws and consequently poorer attachment ability than smaller animals. This expected size-induced reduction in attachmen...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Pattrick, J. G., Labonte, D., Federle, W. Tags: RESEARCH ARTICLE Source Type: research

Measurement and modelling of primary sex ratios for species with temperature-dependent sex determination [RESEARCH ARTICLE]
Melanie D. Massey, Sarah M. Holt, Ronald J. Brooks, and Njal Rollinson For many oviparous animals, incubation temperature influences sex through temperature-dependent sex determination (TSD). Although climate change may skew sex ratios in species with TSD, few available methods predict sex under natural conditions, fewer still are based on mechanistic hypotheses of development, and field tests of existing methods are rare. We propose a new approach that calculates the probability of masculinization (PM) in natural nests. This approach subsumes the mechanistic hypotheses describing the outcome of TSD, by integrating embryon...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Massey, M. D., Holt, S. M., Brooks, R. J., Rollinson, N. Tags: RESEARCH ARTICLE Source Type: research

Water pH limits extracellular but not intracellular pH compensation in the CO2 tolerant freshwater fish, Pangasianodon hypophthalmus [SHORT COMMUNICATION]
Michael A. Sackville, Ryan B. Shartau, Christian Damsgaard, Malthe Hvas, Le My Phuong, Tobias Wang, Mark Bayley, Do Thi Thanh Huong, Nguyen Thanh Phuong, and Colin J. Brauner Preferentially regulating intracellular pH (pHi) confers exceptional CO2 tolerance on fishes, but is often associated with reductions in extracellular pH (pHe) compensation. It is unknown if these reductions are due to intrinsically lower capacities for pHe compensation, hypercarbia-induced reductions in water pH or other factors. To test how water pH affects capacities and strategies for pH compensation, we exposed the CO2 tolerant fish, Pangasianodo...
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Sackville, M. A., Shartau, R. B., Damsgaard, C., Hvas, M., Phuong, L. M., Wang, T., Bayley, M., Huong, D. T. T., Phuong, N. T., Brauner, C. J. Tags: SHORT COMMUNICATION Source Type: research

Rafting on floating fruit is effective for oceanic dispersal of flightless weevils [RESEARCH ARTICLE]
This study provides the first empirical evidence that P. jitanasaius larvae can survive ‘rafting’ on ocean currents and that the eggs and larvae of these weevils have the highest probability to cross the oceanic barrier. This ability may facilitate over-the-sea dispersal of these flightless insects and further shape their distribution and speciation pattern in the Western Pacific islands. (Source: Journal of Experimental Biology)
Source: Journal of Experimental Biology - October 23, 2018 Category: Biology Authors: Yeh, H.-Y., Tseng, H.-Y., Lin, C.-P., Liao, C.-P., Hsu, J.-Y., Huang, W.-S. Tags: RESEARCH ARTICLE Source Type: research

Impact of differences in nutritional quality of wingless and winged aphids on parasitoid fitness [RESEARCH ARTICLE]
Jennifer A.-L. M. Pirotte, Ange Lorenzi, Vincent Foray, and Thierry Hance Winged aphids are described as hosts of lesser quality for parasitoids because a part of their resources is used to produce wings and associated muscles during their development. Host lipid content is particularly important for parasitoid larvae as they lack lipogenesis and therefore rely entirely on the host for this resource. The goal of this study was to determine to what extent winged and wingless aphids differ from a nutritional point of view and whether these differences impact parasitoid fitness, notably the lipid content. We analysed the ene...
Source: Journal of Experimental Biology - October 22, 2018 Category: Biology Authors: Pirotte, J. A.- L. M., Lorenzi, A., Foray, V., Hance, T. Tags: RESEARCH ARTICLE Source Type: research