INSIDE JEB
OUTSIDE JEB
COMMENTARY
- Loss-of-function approaches in comparative physiology: is there a future for knockdown experiments in the era of genome editing?
Summary: We discuss the merits and pitfalls of current knockdown and knockout approaches and advocate for the continued use of knockdown experiments in order to maintain progress in physiological research.
SHORT COMMUNICATION
- Does the left aorta provide proton-rich blood to the gut when crocodilians digest a meal?
Summary: Blood in the left aorta of American alligators does not contain elevated PCO2 levels during digestion.
RESEARCH ARTICLES
- Natural polymorphism in protein kinase G modulates functional senescence in Drosophila melanogaster
Summary: PKG, encoded by the polymorphic foraging gene, confers hypoxia tolerance at the expense of lifespan and healthy aging, indicating a novel role for PKG in aging and senescence.
- Variation in sexual brain size dimorphism over the breeding cycle in the three-spined stickleback
Summary: Sex-specific changes in brain size over the breeding cycle in the three-spined stickleback may be the reason for varying estimates of sexual brain size dimorphism across studies of this species.
- Increased apical sodium-dependent glucose transporter abundance in the ctenidium of the giant clam Tridacna squamosa upon illumination
Summary: The giant clam Tridacna squamosa expresses an apical sodium/glucose cotransporter 1 homolog in the ctenidium that could participate in light-enhanced glucose absorption.
- Sensory feedback independent pre-song vocalizations correlate with time to song initiation
Summary: The number and progression of introductory notes to song in the zebra finch are not affected by removal of sensory feedback.
- Work loop dynamics of the pigeon (Columba livia) humerotriceps demonstrate potentially diverse roles for active wing morphing
Highlighted Article: In pigeons, natural variation in wingbeat frequency, and humerotriceps activation phase and duration, indicate functional plasticity that can effectively power different flight behaviors.
- Pollen reverses decreased lifespan, altered nutritional metabolism and suppressed immunity in honey bees (Apis mellifera) treated with antibiotics
Highlighted Article: Bacteria in pollen confer the ability to inhibit virus replication, extend lifespan and improve overall health in honey bees treated with antibiotics.
- Context-dependent scaling of kinematics and energetics during contests and feeding in mantis shrimp
Editors' Choice: Behavioral context alters kinematic and energetic scaling in animals with spring-powered movements. Variable spring compression likely underlies these context-specific changes, which have implications for theories of contest and feeding behavior.
- Cutaneous respiration by diving beetles from underground aquifers of Western Australia (Coleoptera: Dytiscidae)
Highlighted Article: Subterranean diving beetles survive permanently under water using cutaneous respiration, making them independent of visits to the surface to collect air, but restricting them to a small size.
- Interspecific scaling of blood flow rates and arterial sizes in mammals
Summary: Blood flow rates determine artery sizes in mammals, independent of body mass.
- Motor control of an insect leg during level and incline walking
Highlighted Article: In stick insect hindlegs, muscle activity is adjusted to different mechanical demands during walking, primarily early in stance. Adjustments strongly affect forces/torques but not kinematics and suggest step-by-step control.
- Avian yolk androgens are metabolized rather than taken up by the embryo during the first days of incubation
Highlighted Article: Mass spectrometric analysis using stable isotope labelled androgens shows that maternal androgens in bird egg yolk are not taken up by the embryo during early incubation but rather are metabolized.
- Elevated oxidative stress in pied flycatcher nestlings of eumelanic foster fathers under low rearing temperatures
Summary: The pied flycatcher demonstrates a temperature-dependent association between oxidative stress of offspring and variation in the melanin coloration of their foster father.
- The quantity–quality trade-off: differential effects of daily food availability times on reproductive performance and offspring quality in diurnal zebra finches
Summary: Absence of food in the morning compromises reproductive fecundity but not quality of offspring, whereas food absence in the evening compromises quality (skeletal growth and overall size) of offspring but not reproductive fecundity in continuously breeding diurnal zebra finches.
- 3D ultrastructural organisation of calcium release units in the avian sarcoplasmic reticulum
Summary: 3D reconstructions of calcium release units in the avian heart combined with computer modelling reveal that close clustering of cSR along the Z-line is vital for rapid propagation of the Ca2+ signal, enabling strong, fast contractions of the avian heart.
- Genetic and environmental effects on the scaling of metabolic rate with body size
Summary: Daphnia magna shows a genotype-by-temperature interaction in the allometric intercept of metabolic rate, but no genetic effects on the allometric slope.
- Morph- and sex-specific effects of challenging conditions on maintenance parameters in the Gouldian finch
Highlighted Article: Gouldian finches exhibit physiological divergence between individuals of different morphs and between reproductive partners under energetically demanding conditions (heatwave, moult or reproduction).
- Zonation of Ca2+ transport and enzyme activity in the caeca of rainbow trout – a simple structure with complex functions
Summary: A novel technique revealed region-specific ion transport properties within the caeca of rainbow trout. Feeding and environmental manipulation altered ion transport characteristics, which changes in enzyme activity supported.
- Softness sensing and learning in Drosophila larvae
Summary: Drosophila melanogaster larvae prefer a soft food substrate. They can learn the softness of agarose gel and evaluate foods by balancing softness and sweetness. Genetic background affects the larval preference for softness.
- Control of breathing and respiratory gas exchange in high-altitude ducks native to the Andes
Summary: Distinct physiological strategies for coping with hypoxia exist across different high-altitude lineages of ducks.
This issue
Other journals from The Company of Biologists
Editor’s choice – A cognitive map in a poison frog
For more than 20 years, frogs and lizards were considered to lack place memory. Now, however, Sabrina Burmeister and her team use a modification of the classic Morris water maze to demonstrate the presence of a cognitive map in green-and-black poison dart frogs.
“Getting the JEB Fellowship was really important early on in my career.”
Cosima Porteus is a Postdoctoral Fellow at the University of Exeter, UK, where she studies how fish sense, interact with and respond to their environment. In this interview, Cosima talks about what motivated her to become a scientist, the people that influenced her career, and her opinion on improving the peer-review system for early career researchers.
Path integration is a navigational strategy that gives an animal an estimate of its position relative to some starting point. In his Review, Thomas Collett details the features of path integration in foraging desert ants and honeybees and explains how, in some cases, well-ordered behaviour might substitute for complex neural circuitry.
The Peter Baker Fellowship is for post-doctoral scientists interested in marine biology research, especially physiological research. It will provide living and travel expenses (up to £3,000) to spend approximately two months working at the Laboratory of the Marine Biological Association, Plymouth, at any time of the year. Bench fees will be waived and a small sum may be available to assist with research expenses. This fund is held in trust by the Physiological Society, The Company of Biologists and the Marine Biological Association. Application deadline: 31 January 2020.
If you’re going to the ICCPB meeting in Ottawa from 5 to 9 August, you can meet some of our Monitoring Editors, chat to JEB Reviews Editor Charlotte Rutledge and pick up free JEB goodies from the Plenary Room!
The Company of Biologists provides grants to fund scientific meetings, workshops and conferences in the fields covered by our journals. Typically, meetings with fewer than 100 people may be granted up to £2,000, increasing up to £6,000 for about 400 people. The next deadline to apply is 02 September 2019.
Rasmus Ern highlights a preprint from Josefin Sundin and colleagues, who found that reducing brain temperature of Atlantic cod by mounting cooling plates on their head only marginally increases the fish’s maximum thermal tolerance.