Current Biology最新文献

{"title":"Periodic excretion patterns of seabirds in flight.","authors":"Leo Uesaka, Katsufumi Sato","doi":"10.1016/j.cub.2025.06.058","DOIUrl":"10.1016/j.cub.2025.06.058","url":null,"abstract":"<p><p>Understanding when and how often seabirds excrete at sea is important for understanding their potential influence on marine ecosystems¹. Whales are known to redistribute nutrients through excretion, the 'whale pump'². Large and widespread populations of seabirds could similarly shape key pelagic ecosystem processes, but such effects cannot be evaluated without basic data on their excretion behavior. Because of the challenges of observing seabirds traveling over the open sea, current knowledge of such effects is restricted to the terrestrial environment, and their excretion characteristics in open ocean are almost entirely unknown. Here, we report our observations of excretions of streaked shearwaters (Calonectris leucomelas) in the open ocean made using a belly-mounted video camera. The streaked shearwaters exhibited a marked tendency to avoid excretion while floating on the sea surface and consistently excreted during flight. Excretion timings showed periodicity, occurring every 4-10 min during daylight hours with inter-event intervals varying within a few minutes. Streaked shearwaters excreted approximately 5% of their body mass per hour, potentially substantial enough to influence flight energetics. Our study opens a path toward evaluating seabirds' contributions to regional nutrient cycles and their epidemiological interactions within marine ecosystems.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":"35 16","pages":"R795-R796"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144882432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The sTDIF signaling peptide modulates the root stele diameter and primary metabolism to accommodate symbiotic nodulation.","authors":"Juliette Teyssendier de la Serve, Pierre Gautrat, Carole Laffont, Zelie Lesterps, Emeline Huault, Florence Guerard, Hélène San Clemente, Marielle Aguilar, Sandra Bensmihen, Bertrand Gakière, Nicolas Frei-Dit-Frey, Florian Frugier","doi":"10.1016/j.cub.2025.07.056","DOIUrl":"https://doi.org/10.1016/j.cub.2025.07.056","url":null,"abstract":"<p><p>Legume plants form specific organs on their root system, the nitrogen-fixing nodules, thanks to a symbiotic interaction with soil bacteria collectively named rhizobia. Rhizobia, however, do not only induce the formation of these nodule organs but also modulate root system architecture. We identified in Medicago truncatula a previously unnoticed increase in the root stele diameter occurring upon rhizobium inoculation. This symbiotic root response, similarly observed in another crop legume, pea, occurs rapidly and locally after rhizobium inoculation, leading to an increased number of vascular cells. Interestingly, this root stele diameter symbiotic response requires tracheary element differentiation inhibitory factor (TDIF) signaling peptides and, notably, the MtCLE37 TDIF-encoding gene whose expression is increased during nodulation, thus being referred to as symbiotic nodulation TDIF (sTDIF). Indeed, a cle37/stdif mutant is not responsive to rhizobium regarding its root stele diameter increase and has a reduced nodule number. Combined transcriptomic and metabolomic analyses revealed that stdif has a defective primary metabolism, notably affecting carbohydrate/sugar accumulation in both roots and nodules. Remarkably, a sucrose or a malate exogenous treatment is able to rescue the rhizobium-induced stele diameter symbiotic response in stdif. This metabolic deregulation is thus instrumental in explaining the altered symbiotic response of the mutant. Overall, this study highlights a novel function of TDIF signaling peptides in legumes plants, which, beyond regulating stele development, also modulates the root primary metabolism adaptations required for symbiotic nodule development.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":""},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144946807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flexible updating of reward and punishment contingencies by VTA GABA neurons.","authors":"Merridee J Lefner, Bita Moghaddam","doi":"10.1016/j.cub.2025.07.021","DOIUrl":"10.1016/j.cub.2025.07.021","url":null,"abstract":"<p><p>In dynamic environments where stimuli predicting reward or punishment unexpectedly change, it is critical to flexibly update behavior while preserving recollection of previous associations. Dopamine and gamma-aminobutyric acid (GABA) neurons in the ventral tegmental area (VTA) are implicated in reward and punishment learning, yet little is known about how each population adapts when the predicted outcome valence changes. To address this, VTA GABA and dopamine population calcium activity fluctuations were measured with fiber photometry while male and female rats learned to associate three discrete auditory cues with three distinct outcomes: reward, punishment, or no outcome within the same session. Contingency learning was determined by quantifying conditioned responding and probability of approach behaviors. After learning, the reward and punishment cue-outcome contingencies were reversed and subsequently re-reversed. The dopamine population displayed the expected adaptation to learning and contingency reversals by increasing the response to appetitive stimuli and decreasing the response to aversive stimuli. By contrast, the GABA population increased activity to all sensory events regardless of valence. Reversing learned contingencies selectively influenced GABA responses to the reward-predictive cue, prolonging increased activity both within and across sessions. Trial-by-trial analysis further confirmed that sustained GABA activity tracks contingency reversal. The valence-specific dissociations in the directionality and temporal progression of VTA GABA and dopamine neuronal activity suggest that these populations serve distinct roles during reward or punishment associative learning and reversal. These findings also describe a novel role for VTA GABA in behavioral flexibility.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":"3973-3985.e3"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12410339/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144764764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal conservation of migratory monarch butterflies requires immediate international coordination.","authors":"D T Tyler Flockhart, Sam Nicol, Iadine Chadès, Greg W Mitchell, Tara G Martin, Richard A Fuller, D Ryan Norris","doi":"10.1016/j.cub.2025.06.068","DOIUrl":"10.1016/j.cub.2025.06.068","url":null,"abstract":"<p><p>The eastern North American monarch butterfly, known for its spectacular annual migration between Mexico, USA, and Canada, is currently the focus of intense conservation attention to minimize extinction risk and reach a conservation target of approximately 132 million individuals (equivalent to occupying 6 ha of overwintering habitat in Mexico).¹ Given that migratory eastern North American monarchs breed over successive breeding generations across a vast area,¹^,²^,³^,⁴^,⁵^,⁶ reaching this conservation objective must account for the inherent uncertainties of undertaking conservation actions across space and time.⁷^,⁸^,⁹^,¹⁰^,¹¹ We integrated a density-dependent full-annual-cycle matrix population model with stochastic dynamic programming to identify the optimal sequence of conservation actions (restoring habitat in three different breeding regions or protecting habitat on the wintering grounds), spanning three countries, to reach each of three objectives: maximize population viability, meet the population target, and maximize population size. Using an annual budget of $30 million over 5 years, we find that a coordinated approach that would primarily focus on habitat restoration in the central USA would best help achieve each of the three recovery objectives. Importantly, monarchs had a higher chance of reaching each conservation objective following a strategy that was coordinated across all three nations and commenced immediately rather than be delayed. Our results provide quantitative evidence for the necessity of coordinated international efforts to conserve migratory species and a tool for decision-makers in Canada, USA, and Mexico to recover this iconic and highly threatened butterfly.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":"4011-4018.e4"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144706795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disentangling prediction error and value in a formal test of dopamine's role in reinforcement learning.","authors":"Alexandra A Usypchuk, Etienne J P Maes, Megan Lozzi, Dimitrios K Avramidis, Geoffrey Schoenbaum, Guillem R Esber, Matthew P H Gardner, Mihaela D Iordanova","doi":"10.1016/j.cub.2025.06.076","DOIUrl":"10.1016/j.cub.2025.06.076","url":null,"abstract":"<p><p>The discovery that midbrain dopamine (DA) transients can be mapped onto reward prediction errors (RPEs), the critical signal that drives learning, is a landmark in neuroscience. Causal support for the RPE hypothesis comes from studies showing that stimulating DA neurons can drive learning under conditions where it would not otherwise occur.¹^,²^,³ However, such stimulation might also promote learning by adding reward value and indirectly inducing an RPE. This added value could support new learning even when it is insufficient to support instrumental behavior.⁴^,⁵ Thus, these competing interpretations are challenging to disentangle and require direct comparison under matched conditions. We developed two computational models grounded in temporal difference reinforcement learning (TDRL)⁶^,⁷^,⁸ that dissociate the role of DA as an RPE versus a value signal. We validated our models by showing that they both predict learning (unblocking) when ventral tegmental area (VTA) DA stimulation occurs during expected reward delivery in a behavioral blocking design and confirmed this behaviorally. We then contrasted the models by delivering constant optogenetic stimulation during reward across both learning phases of blocking. The value model predicted blocking; the RPE model predicted unblocking. Behavioral results aligned with the latter. Moreover, the RPE model uniquely predicted that constant stimulation would unblock learning at higher frequencies (>20 Hz) when the artificial error alone drives learning. This, too, was confirmed experimentally. We demonstrate a principled computational and empirical dissociation between DA as an RPE versus a value signal. Our results advance understanding of how DA neuron stimulation drives learning.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":"4019-4027.e7"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144752674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A switch to non-proliferative growth sustains Drosophila wing development during the early pupal stage.","authors":"Khaoula El Marzkioui, Isabelle Gaugué, Ettore De Giorgio, Christelle Anguille, Pierre Léopold, Laura Boulan","doi":"10.1016/j.cub.2025.07.020","DOIUrl":"10.1016/j.cub.2025.07.020","url":null,"abstract":"<p><p>Understanding how final organ size is established during development remains a fundamental yet unresolved question in biology. Size determination depends on two key processes: how organs increase their mass and how they stop growing upon reaching an appropriate size. Over the past few decades, organ transplantation and regeneration experiments have provided broad insights into size determination.¹^,² In particular, research on Drosophila imaginal discs has started disentangling the complex integration of growth control with developmental processes.³^,⁴^,⁵ The wing disc is a highly proliferating monolayer epithelium during larval stages, with cell proliferation slowing and eventually halting at the larva-to-pupa (L/P) transition. Since growth has traditionally been associated with proliferation, the current model postulates that proliferation arrest determines final tissue size. Consequently, the L/P transition is believed to mark a switch between growth and morphogenesis, and understanding proliferation arrest at that stage has been the focus of both experimental and theoretical studies.⁶^,⁷^,⁸^,⁹^,¹⁰^,¹¹ Here, through 3D reconstruction and volume measurements, we show that wing disc growth continues throughout the L/P transition, only arresting later during the pupal period. This reveals a previously uncharacterized phase of growth in the early pupal stage that takes place during wing eversion, expansion, and elongation. Furthermore, we demonstrate that pupal wing growth is driven by an increase in cell volume, with an important contribution from insulin/insulin growth factor (IGF) signaling activated by fat body-derived Dilp6. These findings challenge the prevailing model of imaginal wing development and open new avenues for the study of growth arrest and organ size determination.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":"4043-4049.e3"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144768481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new time tree of birds reveals the interplay between dispersal, geographic range size, and diversification.","authors":"Santiago Claramunt, Catherine Sheard, Joseph W Brown, Gala Cortés-Ramírez, Joel Cracraft, Michelle M Su, Brian C Weeks, Joseph A Tobias","doi":"10.1016/j.cub.2025.07.004","DOIUrl":"10.1016/j.cub.2025.07.004","url":null,"abstract":"<p><p>The spatial and temporal dynamics of biodiversity are shaped by complex interactions among species characteristics and geographic processes. A key example is the effect of dispersal on geographical range expansion and gene flow, both of which may determine speciation rates. In this study, we constructed a time-calibrated phylogeny of over 9,000 bird species and leveraged extensive data on avian traits and spatial occurrence to explore the connections between dispersal, biogeography, and speciation. Phylogenetic path analyses and trait-dependent diversification models reveal that geographic range size is strongly associated with the hand-wing index, a proxy for wing aspect ratio related to flight efficiency and dispersal ability. By contrast, we found mixed evidence for the effect of dispersal on diversification rates: dispersive lineages show either slightly higher speciation rates or higher extinction rates. Our results therefore suggest that high dispersal ability increases range expansion and turnover, perhaps because dispersive lineages expand into islands or other geographically restricted environments and have lower population sizes. Our results highlight the nuanced and interconnected roles of dispersal and range size in shaping global patterns of avian diversification and biogeography and provide a richly sampled phylogenetic template for exploring a wide array of research questions in macroecology and macroevolution.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":"3883-3895.e4"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144759456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diving behaviour and physiology of the Korean Haenyeo.","authors":"J Chris McKnight, Bateman Solms, Matthew Jensen, Jamie Turnbull, Steve Balfour, Maaike Laagland, Mathijs Bronkhorst, Ho Joon Lee, Gyoungri Kang, Joo Young Lee, Adrian Bell, Gordon Hastie, Melissa Ilardo","doi":"10.1016/j.cub.2025.06.066","DOIUrl":"10.1016/j.cub.2025.06.066","url":null,"abstract":"<p><p>There is a long history of breath-hold diving cultures in East Asia, with references in Japanese chronicles as early as the third century BC. Given evidence of genetic adaptations for phenotypes associated with enhanced diving capacity within such populations¹, it is likely they hold the most prodigious human diving abilities - abilities that may be akin to semi-aquatic mammals, and even some marine mammals. Yet, a dearth of fine-scale information exists on the combined natural diving behaviour and physiological responses within these diving populations. One such extraordinary population is the all-female Haenyeo. Here, we assess the fine-scale diving behaviours and physiological responses of these women during natural harvest diving. Our results show that Haenyeo divers demonstrate the highest proportions of time underwater of any humans, also exceeding those of semi-aquatic mammals and being comparable with some marine mammals. Additionally, they do not exhibit an overt cardiovascular depression, or 'dive response', classically associated with consummate diving mammals.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":"35 16","pages":"R797-R798"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144882413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wolves use diverse tactics to track partially migratory prey.","authors":"Avery L Shawler, Kristin J Barker, Wenjing Xu, Kenneth J Mills, Tony W Mong, Arthur D Middleton","doi":"10.1016/j.cub.2025.07.015","DOIUrl":"10.1016/j.cub.2025.07.015","url":null,"abstract":"<p><p>Some predators move long distances to track migratory prey.¹^,²^,³ This phenomenon, known as migratory coupling,¹ has been observed in wolves that track migratory caribou in the Arctic.⁴^,⁵^,⁶^,⁷ By contrast, most wolves elsewhere are highly territorial and thought to be non-migratory-particularly during the denning and pup-rearing season.⁸^,⁹ Recent advances in wildlife tracking have illuminated widespread individual variation in seasonal movements of partially migratory prey,¹⁰^,¹¹^,¹²^,¹³^,¹⁴^,¹⁵^,¹⁶^,¹⁷^,¹⁸ but little is known about how wolves respond to such varied behaviors. Using concurrent GPS data (2019-2021) from 19 gray wolves (Canis lupus) and 99 elk (Cervus canadensis) from a large, partially migratory herd in the eastern Greater Yellowstone Ecosystem, we quantified wolf movement strategies based on overlaps between wolf packs' seasonal ranges and between wolf and elk summer ranges. We found that wolves exhibited a range of movement responses, including migrating, commuting, and remaining resident. Additionally, some packs moved pups from den sites to rendezvous sites along elk migration routes, or even within elk summer range, challenging the long-accepted notion that juvenile carnivores act as spatial anchors. The diverse strategies wolves employ to track migratory prey highlight how the plasticity and variation of migratory behaviors in their ungulate prey can translate to dynamic wolf space use. This suggests that changes in ungulate mobility-for instance, due to climate or land-use change-may reverberate across trophic levels, reshaping predator movement patterns and influencing broader ecosystem dynamics.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":"4035-4042.e3"},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144768482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrections in single-cell migration path in vivo are controlled by pulses in polar Rac1 activation.","authors":"Dennis Hoffmann, Tal Agranov, Lucas Kühl, Laura Ermlich, Michal Reichman-Fried, Benjamin D Simons, Nir S Gov, Erez Raz","doi":"10.1016/j.cub.2025.07.063","DOIUrl":"https://doi.org/10.1016/j.cub.2025.07.063","url":null,"abstract":"<p><p>Directed migration of single cells is central to a large number of processes in development and adult life. Corrections to the migration path of cells are often characterized by periodic loss of polarity that is followed by the generation of a new leading edge in response to guidance cues, a behavior termed \"run and tumble.\" While this phenomenon is essential for accurate arrival at migration targets, the precise molecular mechanisms responsible for the periodic changes in cell polarity are unknown. To investigate this issue, we employ germ cells in live zebrafish embryos as an in vivo model and show that a tunable molecular network controls periodic pulsations of Rac1 activity and actin polymerization. This process, which we term \"polar pulsations,\" is responsible for the transitions between the run and tumble phases. In addition, we provide evidence for the role of apolar blebbing activity during tumble phases in erasing the memory of the previous front-back polarity of the migrating cell. To understand how the molecular components give rise to this distinct behavior, we develop a minimal mathematical model of the biochemical network that accounts for the observed cell behavior. Together, our in vivo findings and the mathematical model suggest that a pulsatory signaling network regulates the accuracy of individual cell migration.</p>","PeriodicalId":11359,"journal":{"name":"Current Biology","volume":" ","pages":""},"PeriodicalIF":7.5,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144946737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}