Journal of Experimental Biology最新文献_第4页

Eastern oysters alter inducible defense mechanism of shell strengthening with age. 随着年龄的增长，牡蛎壳强化的诱导防御机制发生了改变。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-07-01 Epub Date: 2025-07-07 DOI: 10.1242/jeb.250143

Sarah H Roney, Gary H Dickinson, Benjamin A Belgrad, Marc J Weissburg

{"title":"Eastern oysters alter inducible defense mechanism of shell strengthening with age.","authors":"Sarah H Roney, Gary H Dickinson, Benjamin A Belgrad, Marc J Weissburg","doi":"10.1242/jeb.250143","DOIUrl":"10.1242/jeb.250143","url":null,"abstract":"Eastern oysters, Crassostrea virginica, use inducible defenses in the form of strengthened shells to reduce their risk of predation. Inducible defenses often have trade-offs between the costs and benefits associated with the organism's fitness, as developing defenses requires energetic resources. Shell strength is a product of the amount of material laid by the animal (thickness) and the material properties of the shell (e.g. hardness and fracture resistance). Previous studies have suggested that oysters may trade off between shell thickness or shell hardness as a mechanism for increasing shell strength against predation, which are hypothesized to have different energetic requirements. The present study analyzed the shell structural (thickness of composite layers) and micromechanical properties (microhardness and crack propagation tested within individual shell layers) of predator-induced and non-induced juvenile oysters at 4 and 8 weeks post-settlement to determine which shell strengthening mechanism oysters use in response to predator cues. Younger juveniles did not display any significant differences in micromechanical shell properties or shell thickness as a result of induction, though some marginal differences were detected. In contrast, older juveniles use a combination of increased hardness and thickness in shell defense, where induced oysters were 33% thicker overall and 12% harder within their outer prismatic layer. This suggests that oysters alter shell strength using multiple defense mechanisms depending on age, and we postulate that animals switch mechanisms when necessary to balance the advantages and associated costs of defense with an individual's physiological needs for growth.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144284861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Innate visual attraction before, during and after escape from adverse substrates in carpenter ants. 木蚁在逃离不利基质之前、期间和之后的先天视觉吸引力。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-07-01 Epub Date: 2025-07-08 DOI: 10.1242/jeb.250278

Yusuke Notomi, Shigeto Dobata, Tomoki Kazawa, So Maezawa, Shigehiro Namiki, Ryohei Kanzaki, Stephan Shuichi Haupt

{"title":"Innate visual attraction before, during and after escape from adverse substrates in carpenter ants.","authors":"Yusuke Notomi, Shigeto Dobata, Tomoki Kazawa, So Maezawa, Shigehiro Namiki, Ryohei Kanzaki, Stephan Shuichi Haupt","doi":"10.1242/jeb.250278","DOIUrl":"10.1242/jeb.250278","url":null,"abstract":"Many animals exhibit an innate attraction to dark areas or objects, driving orientation behaviours such as beacon aiming. In ants, some species do not appear to display beacon aiming. Here, we show that in one such species, Camponotus japonicus, the behaviour is triggered when crossing liquid-covered surfaces, regardless of locomotor pattern and the presence of water in the liquid. Once initiated, beacon aiming persisted even after the ants transitioned from water to dry substrates, as evidenced by their reorientation towards a displaced beacon. Beacon aiming could be observed before the ants fully transitioned from a dry substrate to a liquid-covered surface: when the ants were isolated on a water-surrounded platform, attraction to a beacon emerged while they were contacting the water, before finally deciding to swim towards the beacon. Adverse substrate conditions in general appear to be a factor triggering beacon aiming as we also identified one condition (so far) in which even liquid immersion was not required for beacon aiming, namely upside-down walking. These results indicate that beacon aiming in C. japonicus is performed before, during and after escape from adverse substrates. Evidence that substrate conditions can alter seemingly hardwired responses suggests that insects may adjust even simple behaviours in response to environmental conditions in a more sensitive way than commonly assumed.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144484659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spectral preferences of mosquitos are altered by odors. 蚊子的光谱偏好会因气味而改变。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-07-01 Epub Date: 2025-07-09 DOI: 10.1242/jeb.250318

Adam J Blake, Jeffrey A Riffell

{"title":"Spectral preferences of mosquitos are altered by odors.","authors":"Adam J Blake, Jeffrey A Riffell","doi":"10.1242/jeb.250318","DOIUrl":"10.1242/jeb.250318","url":null,"abstract":"Vision underlies many important behaviors in insects generally and in mosquitos specifically. Mosquito vision plays a role in predator avoidance, mate finding, oviposition, locating vertebrate hosts and vectoring disease. Recent work has shown that when sensitized to CO2, the visual responses of Aedes aegypti are wavelength dependent, but little is known about how other olfactory stimuli can modulate visual responses. The visual cues associated with flowers, vertebrate hosts or oviposition sites differ substantially and it is possible that odors might prime the mosquito visual system to respond to these different resources. To investigate the interplay of olfactory and visual cues, we adapted previously used wind tunnel bioassays to use quasi-monochromatic targets (390-740 nm) created with novel LED synthesizers. We coupled these visual targets with CO2 and the odors representative of vertebrate hosts, floral nectar or oviposition sites and assessed responses via 3D tracking of female mosquitos. When CO2 alone was present, we observed a lower preference for wavelengths in the green portion of the visible spectrum with a gradual increase as wavelengths moved towards the violet and red ends of the spectrum. However, when odors associated with both flowers and oviposition sites were present, we observed significant increases in mosquito preference for green (475-575 nm) stimuli. In contrast, when vertebrate host odor was present, we saw increased preference for stimuli across the entire visible spectrum. These odor shifts in mosquito spectral preferences suggest these preferences are not fixed and shift depending on the behavioral context.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144333205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The impact of landscape complexity and composition on honey bee visual learning. 景观复杂性和组成对蜜蜂视觉学习的影响。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-07-01 Epub Date: 2025-07-04 DOI: 10.1242/jeb.250057

Georgina Hollands, Jake L Snaddon, Philip L Newland, Suleiman M Sharkh

{"title":"The impact of landscape complexity and composition on honey bee visual learning.","authors":"Georgina Hollands, Jake L Snaddon, Philip L Newland, Suleiman M Sharkh","doi":"10.1242/jeb.250057","DOIUrl":"10.1242/jeb.250057","url":null,"abstract":"Over the past few decades there has been an overall decline in the number of pollinators, including wild bees, partly due to stress factors such as the availability of food resources, nest site availability and pesticide usage. Managed honey bees have also been negatively impacted in certain regions, such as the USA. One of the major stress factors facing bees currently is land use change, where natural landscapes are decreasing and often converted to either agricultural or urban land. Here, we assess directly the link between landscape diversity, edge density and honey bee learning, by analysing how honey bee visual learning ability varies across different landscapes, using a field-adapted version of the proboscis extension response. It was previously thought that honey bees from hives based in different landscapes may vary in visual learning abilities because of their different experiences and neural plasticity. Thus, bees that have experience in more complex learning environments may do better in learning tasks. To test this, bees were taught to associate a coloured yellow paper strip with a positive sugar reward and a blue coloured strip with a negative salt reward. Results showed that as edge density increased in the landscape, visual learning in bees reduced, and when landscape diversity increased, so did learning. This is important as bees must learn foraging routes, find profitable flowers and develop spatial maps, as well as recognise intruders. If their cognitive abilities are reduced and they are unable to carry out these tasks, this will be detrimental for the continuous development of the colony.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144484661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preprints in comparative physiology - a guide for the preprint curious. 比较生理学的预印本——对预印本好奇的指南。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-07-01 Epub Date: 2025-07-14 DOI: 10.1242/jeb.250590

Charlotte Nelson, Katie E Marshall

引用次数: 0

Causal models of rate-independent damping in insect exoskeleta. 昆虫外骨骼中速率无关阻尼的因果模型。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-07-01 Epub Date: 2025-07-07 DOI: 10.1242/jeb.249940

Arion Pons

{"title":"Causal models of rate-independent damping in insect exoskeleta.","authors":"Arion Pons","doi":"10.1242/jeb.249940","DOIUrl":"10.1242/jeb.249940","url":null,"abstract":"In insect locomotion, the transmission of energy from muscles to motion is a process within which there are many sources of dissipation. One significant but understudied source is the structural damping within the insect exoskeleton itself: the thorax and limbs. Experimental evidence suggests that exoskeletal damping shows frequency (or rate) independence, but investigation into its nature and implications has been hampered by a lack methods for simulating the time-domain behaviour of this damping. Here, synergising and extending results across applied mathematics and seismic analysis, I provide these methods. Existing models of exoskeletal rate-independent damping are equivalent to an important singular integral in time: the Hilbert transform. However, these models are strongly noncausal, violating the directionality of time. I derive the unique causal analogue of these existing exoskeletal damping models, as well as an accessible approximation to them, as Hadamard finite-part integrals in time, and provide methods for simulating them. These methods are demonstrated on several current problems in insect biomechanics. Finally, I demonstrate, for the first time, that these rate-independent damping models show counterintuitive energetic properties - in certain cases, extending to violation of conservation of energy. This work resolves a key methodological impasse in the understanding of insect exoskeletal dynamics and offers new insights into the micro-structural origins of rate-independent damping as well as the directions required to resolve violations of causality and the conservation of energy in existing models.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144248223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phenotypic plasticity in visual opsin gene expression: a meta-analysis in teleost fish. 视觉视蛋白基因表达的表型可塑性：硬骨鱼的荟萃分析。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-07-01 Epub Date: 2025-06-30 DOI: 10.1242/jeb.250332

César Bertinetti, Julián Torres-Dowdall

{"title":"Phenotypic plasticity in visual opsin gene expression: a meta-analysis in teleost fish.","authors":"César Bertinetti, Julián Torres-Dowdall","doi":"10.1242/jeb.250332","DOIUrl":"10.1242/jeb.250332","url":null,"abstract":"Phenotypic plasticity in visual opsin gene expression enables teleost fish to adjust their spectral sensitivity in response to environmental variability, yet the magnitude and drivers of this plasticity remain unresolved. We conducted a meta-analysis of 573 effect sizes from 36 studies to assess the prevalence and strength of opsin gene expression plasticity across teleost fishes, considering stimulus type (internal versus external) and timing of exposure (acute versus developmental). Plasticity of opsin gene expression was widespread and generally strong, with internal stimuli (e.g. hormonal changes) eliciting larger and more consistent responses than external stimuli (e.g. light conditions), particularly in the red-sensitive lws and UV-sensitive sws1 opsin genes. Phylogenetic analysis revealed no significant evolutionary constraints on opsin plasticity, suggesting that the capacity for visual system modulation is broadly distributed across teleost lineages. Our findings highlight the need for future studies to integrate behavioral, molecular and ecological data to evaluate the adaptive significance of opsin plasticity and its role in shaping visual performance under changing environmental conditions.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144208701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Prolonged fasting and glucocorticoid exposure drive dynamic DNA methylation in elephant seals. 长期禁食和糖皮质激素暴露驱动海象动态DNA甲基化。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-06-30 DOI: 10.1242/jeb.250046

Emily F Gibson, Julia María Torres-Velarde, David C Ensminger, Diana D Moreno-Santillán, Daniel E Crocker, José Pablo Vázquez-Medina

{"title":"Prolonged fasting and glucocorticoid exposure drive dynamic DNA methylation in elephant seals.","authors":"Emily F Gibson, Julia María Torres-Velarde, David C Ensminger, Diana D Moreno-Santillán, Daniel E Crocker, José Pablo Vázquez-Medina","doi":"10.1242/jeb.250046","DOIUrl":"https://doi.org/10.1242/jeb.250046","url":null,"abstract":"Elephant seals experience prolonged fasting while breeding, molting, and undergoing postnatal development. Fasting elephant seals adjust neuroendocrine function and gene expression to cope with potentially detrimental effects associated with extended fasting. DNA methylation alters gene expression by modulating accessibility to regions necessary to initiate transcription. The role of fasting and glucocorticoids on DNA methylation in elephant seals is understudied. We evaluated whether fasting alters global blood DNA methylation, the potential correlation between increased glucocorticoids and methylation, and the effects of glucocorticoids on DNA methylation in cultured elephant seal muscle cells. We found that fasting transiently increases blood DNA methylation and that blood DNA methylation levels correlate with plasma cortisol. We then conducted bioinformatic analyses to identify regions in the elephant seal glucocorticoid receptor (GR) promoter that influence gene transcription through methylation (CPG islands). We identified one CpG island within the putative GR promoter. Methylation in this region, however, was unaffected by prolonged fasting. We then investigated whether exogenous glucocorticoids alter DNA methylation and gene expression profiles in seal muscle cells in primary culture (myotubes). Exposure to glucocorticoids for 12 or 48 hours decreased DNA methylation while upregulating pro-survival gene expression in elephant seal muscle cells. Our results show that whereas prolonged fasting transiently increases DNA methylation in elephant seal blood, sustained exposure to exogenous glucocorticoids decreases DNA methylation and activates a pro-survival transcriptional program in seal muscle cells. Therefore, our results suggest that DNA methylation is a plastic, potentially cell-type-specific response that regulates gene expression in fasting elephant seals.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Navigating in clutter: How bumblebees optimize flight behaviour through experience. 在混乱中导航：大黄蜂如何通过经验优化飞行行为。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-06-30 DOI: 10.1242/jeb.250514

Manon Jeschke, Maximilian Stahlsmeier, Martin Egelhaaf, Olivier J N Bertrand

{"title":"Navigating in clutter: How bumblebees optimize flight behaviour through experience.","authors":"Manon Jeschke, Maximilian Stahlsmeier, Martin Egelhaaf, Olivier J N Bertrand","doi":"10.1242/jeb.250514","DOIUrl":"https://doi.org/10.1242/jeb.250514","url":null,"abstract":"Bumblebees are excellent navigators that travel long distances while following paths to known locations. They forage not only in open terrain but also in cluttered environments where obstacles force them to deviate from direct paths. This study investigates the underexplored aspect of how bees become experienced foragers and optimize flight behaviour in cluttered terrains. We recorded flight trajectories of novice bees with no prior experience in navigating cluttered laboratory environments and monitored their behavioural performance as they gained experience on subsequent foraging trips through numerous obstacles. By controlling for experience levels, we analysed how flight characteristics evolve with increasing expertise. Successful navigation in cluttered terrain requires avoiding collisions with obstacles. This is only possible if these can be detected through visual features such as the retinal displacement of contrast edges. Obstacles which are harder to detect and to avoid by the bees may affect their flight performance. By introducing transparent objects into our dense environment, we challenged collision avoidance and learning mechanisms, analysing the impact on flight optimization under different environmental conditions. Our findings reveal that experienced bees fly similar paths through clutter and quickly adapt their flights regardless of their training environment. However, the specific paths followed are influenced by environmental conditions. Transparent objects primarily affect naive bees' flight patterns while having minimal impact on flight optimization, suggesting that the efficient flights of experienced bees result not solely from reflexive collision avoidance but from learning and previous experience in cluttered environments.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Severe acute hypoxia upregulates anaerobic metabolism in non-reproductive but not queen naked mole-rats. 严重急性缺氧可上调非生殖裸鼹鼠而非裸鼹鼠后的无氧代谢。

IF 2.8 2区生物学

Journal of Experimental Biology Pub Date : 2025-06-30 DOI: 10.1242/jeb.250397

Mohammad Ojaghi, Matthew E Pamenter

{"title":"Severe acute hypoxia upregulates anaerobic metabolism in non-reproductive but not queen naked mole-rats.","authors":"Mohammad Ojaghi, Matthew E Pamenter","doi":"10.1242/jeb.250397","DOIUrl":"https://doi.org/10.1242/jeb.250397","url":null,"abstract":"Most vertebrates upregulate anaerobic metabolism in severe hypoxia, which results in metabolic acidosis that must be resolved during reoxygenation. Naked mole-rats (NMRs) are hypoxia-tolerant mammals and drastically reduce their metabolic rate while maintaining systemic pH homeostasis during acute hypoxia. Whether or not NMRs employ anaerobic metabolism in hypoxia is currently debated. Given the robust systemic hypoxic hypometabolism of this species we hypothesized that anaerobic metabolism is recruited on a tissue-specific basis that varies between developmental stages and colony caste position. To test this, we treated subordinate juvenile and adult, and breeding (queen) NMRs in normoxia (21% O2) or hypoxia (3% O2) for 1 h, and then measured blood lactate, glycolytic enzyme activity, and the expression of genes that encode for enzymes involved in glycogen and glucose metabolism, and lactate transport. We found that (1) blood lactate levels increase similarly during hypoxia across developmental stages and castes; but that (2) glycolytic activity increased or remained stable in subordinates and juveniles but was unchanged or reduced in queens; (3) MCT4 gene expression decreased markedly in subordinate and juvenile brain and increased in muscle and kidney, but was unchanged in queens; and (4) the expression of genes associated with glycogenolysis and gluconeogenesis varied across tissues in subordinates/juveniles with some markers being down or upregulated or unchanged, but were always unchanged or downregulated queens. Taken together, our results suggest that hypoxia upregulates glycolysis and glycogen mobilization in subordinates and juveniles, but not in queens.","PeriodicalId":15786,"journal":{"name":"Journal of Experimental Biology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0