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Tracking data highlight the importance of human-induced mortality for large migratory birds at a flyway scale
Get PDFFunding: Aldina M. A. Franco's work was financed by the FEDER Funds through the Operational Competitiveness Factors Program — COMPETE and by National Funds through FCT – Foundation for Science and Technology within the scope of the project Birds on the move ‘POCI-01-0145-FEDER-028176’, by InBIO (UID/BIA/50027/2013 and POCI-01-0145-FEDER-006821), and by the Natural Environment Research Council (NERC), via the EnvEast DTP, and NERC and Engineering and Physical Sciences Research Council (EPSRC), via the NEXUSS CDT Training in the Smart and Autonomous Observation of the Environment. Funding for the development of the GPS tracking devices was provided by NERC (NE/K006312), Norwich Research Park Translational Fund, University of East Anglia Innovation Funds and Earth and Life Systems Alliance funds. Andrea Santangeli acknowledges support from the European Commission through the Horizon 2020 Marie Skłodowska-Curie Actions individual fellowships (Grant no. 101027534). Alessandro Andreotti thanks for the funding received by the European Commission through the Egyptian vulture LIFE project “Measures for the conservation of the Egyptian vulture in Italy and in the Canary Islands” (LIFE16/NAT/IT/000659) and the support provided by Carabinieri Forestali, Stazione Ornitologica Calabrese and De Rerum Natura. Tagging and tracking of Eleonora's falcons from Greece were conducted in the framework of the projects ‘LIFE13 NAT/GR/000909 Conservation measures to assist the adaptation of Falco eleonorae to climate change’ with the financial support of the European Union LIFE Instrument and the Green Fund and ‘Survey and Conservation of Seabirds in Greece’ funded by A.G. Leventis foundation. Flavio Monti acknowledges support from “Progetto Falco pescatore" (and project collaborators) and wants to thank the Tuscan Archipelago National Park, the Maremma Regional Park, the Diaccia Botrona Natural Reserve, the WWF Orbetello Lagoon Natural Reserve and the WWF Orti-Bottagone Marsh Natural Reserve, under the Tuscany Region administration, in Italy. Joan Real and Antonio Hernández-Matías are deeply grateful to Grup de Naturalistes d'Osona-ICHN, Grup d'Anellament de Calldetenes-Osona (GACO), Servei de Biodiversitat de la Generalitat de Catalunya, Ferrovial S.A., Consoci per a la Gestió de Residus Urbans d'Osona, Ministerio de Transición ecológica of Spain (V. Matarranz and A. Díaz). Funding was provided by project PID2020-117909RBI00 funded by MCIN/AEI/10.13039/501100011033 from the National Plan of the Ministry of Science, Innovation and Universities and Red Eléctrica de España SAU, Fundació Catalunya-La Pedrera and Diputación de Barcelona. Joao L. Guilherme was funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Actions grant agreement no. 766417. This research was supported by generous donors, including B. Bahar, S. İşmen, Ö. Külahçıoğlu, B. Över, B. Özkan, A. Peterson, E. Özgür, S. Reyent, C. Sertoğlu, B. Watkins, the Sigrid Rausing Trust and the Whitley Fund. Ç.H·S is grateful to H. Batubay Özkan and Barbara Watkins for their support of the Biodiversity and Conservation Ecology Lab at the University of Utah School of Biological Sciences. orinne J. Kendall and collaborators are very grateful for the donor support provided by Association of Zoos and Aquariums (AZA), AZA SAFE (Saving Animals From Extinction), Dallas Zoo, Disney Conservation Fund, Leiden Conservation Foundation, National Geographic Society, Taronga Conservation Society Australia, and The Mohamed bin Zayed Species Conservation Fund. Damijan Denac thanks Comita d.d. and Elektro Ljubljana d.d. for supporting White Stork telemetry in Slovenia. David R. Barber is grateful to Wallace Research Foundation, The Acopian Family, Hawk Mountain Sanctuary, VulPro (South Africa), Clive Barlow, The Gambian Department of Parks and Wildlife Management, Endangered Wildlife Trust (South Africa). This work was financially supported by the US National Science Foundation, the Christensen Fund, National Geographic Society, the Whitley Fund for Nature, Faruk Yalçın Zoo and KuzeyDoğa’s donors, Turkey’s Ministry of Forestry and Water Affairs General Directorate of Nature Conservation and National Parks, NorthStar Science and Technology, HawkWatch International, the University of Utah, and The Peregrine Fund. Gradimir Gradev acknowledges funding by Project LIFE for Lesser Kestrel, LIFE19 NAT/BG/001017. Hristo Peshev thanks funding provided by the projects; ‘Recovery of the Populations of Large European Vultures in Bulgaria’ (LIFE08 NAT/BG/000278), ‘Vultures back to LIFE - Bright Future for Black Vulture in Bulgaria’ (LIFE14 NAT/BG/000649) funded by the European Union and project ‘Saving the Balkans’ last vultures: introducing Vulture Safe Areas as a model for scavenger conservation in the Anthropocene’ funded by Whitley Fund for Nature. Inês Catry was funded by contract 2021.03224.CEECIND. Funding for the work on rough-legged buzzards in Norway was provided by the Norwegian Environment Agency and the Environment departments at the Office of the County Governors of Troms and Finnmark, Trøndelag, Innlandet, Vestfold and Telemark, Oslo and Viken, Agder and Vestland. This study was funded by the Max-Planck Institute of Animal Behavior and the German Air and Space Administration (DLR). Partial funding was provided by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy – EXC 2117–422037984. Tagging of common cranes in Estonia was supported by institutional research funding (IUT21-1) at the Estonian Ministry of Education and Research, by the Environmental Investment Centre Projects 2015–2017, and by Research Development Projects from Estonian University of Life Sciences. A significant proportion of the GPS birds provided by Ana Bermejo-Bermejo and Javier de la Puente were marked as part of the Migra programme developed by SEO/BirdLife between 2011 and 2021 and funded by Fundación Iberdrola España. Funding was provided by Interreg POCTEFA Ecogyp (EFA 089/15). The telemetry of Montagu's Harrier in the Czech Republic was supported by the European Union under the Operational Program Environment, project No. CZ.05.4.27/0.0/0.0/19_130/0010743. Mansoor H. AlJahdhami thanks the Office for Conservation of the Environment, Diwan of Royal Court. Manuel Galán is grateful to Ministerio para la Transición Ecológica y Reto Demográfico. Marcin Tobolka thanks funding from National Science Centre (Poland), 2016/23/D/NZ8/01902. Māris Strazds acknowledges funding by Administration of Latvian Environmental Protection Fund, and the Latvian Ornithological Society. Martin Wikelski acknowledges partial funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's ExcellenceStrategy – EXC 2117–422037984. Michael J. McGrady thanks the Environment Authority of Oman for issuance of permits and field support and the Environment Society of Oman for administrative and logistical support. Munir Z. Virani thanks the Band Foundation, The Peregrine Fund, Whitley Fund for Nature, National Geographic Society, Simon Thomsett, Narok County Government, Kenya Wildlife Service and Matira Safaris. Orr Spiegel acknowledges funding by the Binational Science Foundation (BSF) 822/2019 grant. Pauline L. Kamath thanks support from NSF-BSF Ecology and Evolution of Infectious Diseases (EEID) Grant 2015904; USDA—National Institute of Food and Agriculture Hatch Project Nos. ME021908 and ME022402 to PLK. Peter Palatitz was funded by LIFE11/NAT/HU/000926. ainer Raab thanks the support from LIFE EUROKITE project (LIFE18 NAT/AT/000048). They acknowledge funding through the WUR Knowledge Base Program: KB36 Biodiversity in a Nature-Inclusive Society (project number KB36-5200044844) - which is supported by the Dutch Ministry of Agriculture, Nature and Food Quality. Ran Nathan thanks the Minerva Centre for Movement Ecology and Grants BSF-255/2008, BSF-904/2015, DIP NA 846/1-1, GIF-999-66.8/2008, JNF-KKL 14-093-01-6, ISF 2525/16 to RN for their kind support. his work was supported by grant no. I-1465-413.13/2018 of the German-Israeli Foundation for Scientific Research and Development (GIF). Ron Efrat was supported by the Israeli Academy of Science's Adams Fellowship and the Ben-Gurion University's Negev Fellowship. Salim Javed would like to thank the Environment Agency-Abu Dhabi for their support. Simeon A. Marin thanks the Project Greater chance for Lesser Kestrel (Falco naumanni) in Bulgaria - Lesser Kestrel Recovery, LIFE11 NAT/BG/360. Šimon Krejčí was supported by the University of Veterinary Sciences Brno grant no. IGA 204/2023/FVHE. Steffen Oppel and Volen Arkumarev highlight that their work was carried out in the framework of the LIFE projects “The Return of the Neophron” (LIFE10 NAT/BG/000152) and “Egyptian Vulture New LIFE” (LIFE16 NAT/BG/000874, www.LifeNeophron.eu) funded by the European Union and co-funded by the A. G. Leventis Foundation, MAVA Foundation, and the BirdLife GEF/UNDP Migratory Soaring Birds project. Steven R. Ewing would like to thank the private individuals and organisations that funded the RSPB's Hen Harrier tagging programme, particularly the European Commission's LIFE programme through the Hen Harrier LIFE project (LIFE13 NAT/UK/000258), Northern England Raptor Forum (NERF), Lothian and Borders Raptor Study Group, Lush Retail Limited, Natural Resources Wales, Scottish and Southern Energy and the Welsh Government. Tracking of Imperial eagle in Bulgaria was funded by the LIFE Program of the European Union under the project “Conservation of Imperial Eagle and Saker Falcon in key Natura 2000 sites in Bulgaria” (LIFE07 NAT/BG/000068). Tomáš Veselovský acknowledges support from the Pannon Eagle LIFE project (LIFE15/NAT/HU/000902). Tagging of short-toed eagles in Italy was funded by Parco Regionale Gallipoli Cognato e Piccole Dolomiti Lucane. Wayne M. Getz was funded by the National Science Foundation, Grant/Award Number: 1617982; United States-Israel Binational Science Foundation, Grant/Award Number: 904/2015. Rigas Tsiakiris is grateful to the FWFF-Fund for Wild Flora and Fauna (https://www.fwff.org/). Sonja Krüger would like to thank Ezemvelo KZN Wildlife and the Maloti Drakensberg Transfrontier project for their support. Pietro Serroni would like to thank GREFA for their support and collaboration throughout the reintroduction project, Ministero dell'Ambiente e della Sicurezza Energetica for funding the gps tracking activity, Dipartimento Ambiente - Regione Calabria for funding the reintroduction project. Ülo Väli acknowledges support from the EC LIFE programme (project LIFE04NAT/EE/000072), Estonian Environmental Investments Centre (Projects No. 15432 and 15632), the Estonian Environmental Board, Estonian Ministry of Foreign Affairs (Project no. 79-2017) and the Estonian University of Life Sciences (Project No. P180271). Tracking of saker falcons in Slovakia was funded by the LIFE projects LIFE09 NAT/HU/000384 Conservation of Falco cherrug in NE Bulgaria, Hungary, Romania and Slovakia, and LIFE06 NAT/H/000096 Conservation of saker (Falco cherrug) in the Carpathian Basin.Human-induced direct mortality affects huge numbers of birds each year, threatening hundreds of species worldwide. Tracking technologies can be an important tool to investigate temporal and spatial patterns of bird mortality as well as their drivers. We compiled 1704 mortality records from tracking studies across the African-Eurasian flyway for 45 species, including raptors, storks, and cranes, covering the period from 2003 to 2021. Our results show a higher frequency of human-induced causes of mortality than natural causes across taxonomic groups, geographical areas, and age classes. Moreover, we found that the frequency of human-induced mortality remained stable over the study period. From the human-induced mortality events with a known cause (n = 637), three main causes were identified: electrocution (40.5 %), illegal killing (21.7 %), and poisoning (16.3 %). Additionally, combined energy infrastructure-related mortality (i.e., electrocution, power line collision, and wind-farm collision) represented 49 % of all human-induced mortality events. Using a random forest model, the main predictors of human-induced mortality were found to be taxonomic group, geographic location (latitude and longitude), and human footprint index value at the location of mortality. Despite conservation efforts, human drivers of bird mortality in the African-Eurasian flyway do not appear to have declined over the last 15 years for the studied group of species. Results suggest that stronger conservation actions to address these threats across the flyway can reduce their impacts on species. In particular, projected future development of energy infrastructure is a representative example where application of planning, operation, and mitigation measures can enhance bird conservation.Peer reviewe
Reduced nephrin tyrosine phosphorylation impairs podocyte force transmission and accelerates detachment in disease
Get PDFFunding: This work was supported by the Canadian Institutes of Health Research (PJT-148731 to N.J.), Kidney Foundation of Canada (KFOC190002; to N.J.), the Canada Research Chairs Program (to N.J.), the Biotechnology and Biological Sciences Research Council (BB/P027148/1; to M.C.G and P.R.) and the Engineering and Physical Science Research Council (EP/P030017/1; to M.C.G.). Support to C.R.W. was provided by the National Sciences and Engineering Research Council of Canada Postgraduate Scholarship – Doctoral (NSERC PGS D) and a Graduate Entrance Excellence Scholarship from the University of Guelph College of Biological Sciences.Podocytes are specialized kidney cells that form the slit diaphragm (SD), an intercellular filtration barrier against plasma protein loss. The SD is subject to significant mechanical strain which can be amplified in disease, leading to podocyte detachment. One key SD protein that might intercept mechanical strain and transmit adhesion signals is nephrin, although its influence on podocyte force transmission remains uncharacterized. Using immunoblotting and elastic resonator interference stress microscopy (ERISM), we demonstrate that nephrin clustering induces rapid podocyte force transmission and adhesion protein activation (paxillin, FAK, and p130Cas), which require nephrin tyrosine phosphorylation at its three YDxV motifs. Furthermore, using a model of diabetic nephropathy to amplify mechanical stress in vivo, we show that abolishing phosphorylation at YDxV tyrosines leads to exacerbated proteinuria, glomerular hypertrophy, and podocyte detachment. Altogether, this study links nephrin phosphorylation with force transmission, which is likely critical to maintaining podocyte adhesion during many renal pathologies.Peer reviewe
Fertility differences across immigrant generations in the United Kingdom
Get PDFFunding: This paper is part of a project that has received funding from the Scottish Graduate School of Social Science. We gratefully acknowledge the resources provided by the International Max Planck Research School for Population, Health and Data Science (IMPRS-PHDS). Hill Kulu and Sarah Christison’s research was part of a project that has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement 834103).Background : Previous studies have investigated immigrant fertility in various European countries, but only a few have compared the fertility rates of women who migrated as children (1.5 Generation), women born in the host society to foreign-born parents (2 Generation), and women born in the host society with one foreign-born and one native-born parent (2.5 Generation). Objective : This study examines the first-, second-, and third-birth rates of three migrant generation groups in the United Kingdom – 1.5G, 2G, and 2.5G. The study investigates the role of sociocultural factors in shaping their fertility behaviour. Methods : Event history analysis is applied to longitudinal individual-level data (N = 24,228) from the UK Household Longitudinal Study (2009–2021). Results : Pakistani and Bangladeshi women who arrived in the United Kingdom as children exhibit elevated fertility at all birth orders, partly consistent with socialization theory. No clear convergence emerges among women born in the United Kingdom with one immigrant parent and one UK-born parent (2.5G) across all groups from different migrant-origin backgrounds. Instead, certain 2.5G groups show distinct fertility patterns. The influence of sociocultural factors on fertility varies by birth order and migrant generation, highlighting the need for a detailed approach that considers both cultural and socioeconomic dimensions. Contribution : This study is one of the first to differentiate the fertility behaviours of 1.5G, 2G, and 2.5G women in the United Kingdom. It reveals important variations in childbearing behaviour, which have implications for understanding intergenerational differences and the influence of sociocultural factors on migrant fertility.Peer reviewe
Na4Fe3(PO4)2(P2O7)/C composite with porous structure enabling all climate and long-life sodium-ion batteries
Get PDFThis work was supported by the National Natural Science Foundation of China (52202286, 22309002, 52250710680, and 52171217), Natural Science Foundation of Zhejiang Province (LY24B030006), High-end Foreign Experts Recruitment Plan of China (G2023016009L), Key Research and Development Program of Zhejiang Province (2023C01232, and 2024C01057), Basic Research Project of Wenzhou City (G20220016), Science and Technology Plan Project of Wenzhou Municipality (ZG2022032). CW and ARA thank the Faraday Institution NEXGENNA project (FIRG064) for financial support.Na4Fe3(PO4)2(P2O7) (NFPP) with the advantages of low cost and stable crystal structure has been considered a highly promising cathode candidate for sodiumion batteries. However, limited by its undesirable intrinsic conductivity, it still suffers from unsatisfactory electrochemical performance. Herein, we synthesized NFPP/C composites with porous structure (p-NFPP) by a facile selfassembly strategy. Its well-developed pore structure can effectively reduce the ion diffusion path, accelerate electrolyte infiltration and accommodate volume expansion during the charge/discharge process. In addition, in-situ X-ray diffraction revealed the superior structural stability of p-NFPP. They enable a high reversible capacity (104.8 mAh g−1), and good rate performance (75.0 mAh g−1 at 10 A g−1), and excellent cycling stability (a reversible capacity of 85.1 mAh g−1 after 2000 cycles). More importantly, the p-NFPP realizes a stable operation in a wide temperature range of 55°C to −10°C. This work highlights morphology engineering as a powerful strategy to boost the all-climate sodium storage performance of electrode materials.Peer reviewe
Disease landscapes beyond the “Spanish flu” pandemic : temporal patterns, re-centered narratives (1889-1970s)
Get PDF“C'est par l'accent que l'histoire met sur le changement et sur les différences ou écarts affectant les changements qu'elle se distinguish des autres social sciences et principalement de la sociologie”, argued Paul Ricoeur in his classic study La mémoire, l'histoire, l'oubli . We could add to this that change—the passage from one collective situation or circumstance to another—would constitute not only the most specific object of history, but also a major impetus for historians to do research and, in general, for the development of historical science. As Reinhart Koselleck pointed out in Future Pasts. On the semantics of historical time , changes produce a “penetration [rupture] of the horizon of expectations” (taking these as “the future made present”) that inevitably leads to a “restructuring of the space of experiences” (taking these as “the past made present”). Each generation of historians would, thus, feel compelled from the changes occurring in its present to rewrite history in order to re-imagine collective destiny (and vice versa).Non peer reviewe
Directly observing replica symmetry breaking in a vector quantum-optical spin glass
Get PDFFunding: The authors are grateful for funding support from the Army Research Office (Grant #W911NF2210261), NTT Research, and the Q-NEXT DOE National Quantum Information Science Research Center. J.K. and S.G. were supported in part by the International Centre for Theoretical Sciences (ICTS) through participating in the program, Periodically and quasi-periodically driven complex systems (code: ICTS/pdcs2023/6). B.M. acknowledges funding from the Stanford QFARM Initiative and the NSF Graduate Research Fellowship. A.B. and M.W. thank the Stanford Graduate Fellowship and the Joint Quantum Institute Fellowship for support, resp.Spin glasses are quintessential examples of complex matter. Although their ordering lacks complete theoretical understanding, abstract models of spin glasses inform problems in other fields, such as combinatorial optimization and artificial intelligence—where they form a mathematical basis for neural network computing. We demonstrate the ability to realize a spin glass of a distinct driven-dissipative and vector form. By microscopically visualizing its glassy spin states, the technique allows us to directly measure replica symmetry breaking and the resulting ultrametric hierarchical structure. Ultrametricity is known to be emergent in models of evolution, protein folding, and climate change; this work shows it to be directly observable in a physically realized system.Peer reviewe
Efficient burial of labile organic carbon in sediments of oxygenated Icelandic fjords
Get PDFFunding: T. S. Bianchi was funded by the Jon and Beverly Thompson Endowed Chair in the Department of Geological Sciences at Univ. of Florida. We thank the crew of the R/V Skagerak at the University of Gothenburg and funding from the Swedish Research Council (VR 2020-00457). S. B. and T. P. were additionally supported by the Swedish Research Council (VR 2022-04710).Fjords are hotspots of organic carbon (OC) burial, making them key components in the global carbon cycle. Recent research shows high marine OC burial even under oxic fjord water columns, broadening the scope of key drivers of OC burial therein. Here, we investigate the fate of marine OC in fjord sediments underlying oxic bottom waters in East Iceland. We estimate OC sources using stable isotopes, degradation using chemical biomarkers, and burial using 210Pb and 137Cs profiles. The average OC accumulation rates in East Iceland fjords was ~15 g OC m-2 yr-1, lower than the fjord global average of 54 g OC m-2 yr-1. Marine OC was the overwhelming source of OC to sediments and accounted for 91% of the OC buried in Iceland. The gradient in OC source from the head-to-mouth of the fjords was minimal, due to limited terrestrial vegetation and soil cover, low riverine inputs, and effective exchange with coastal waters. Lignin and total hydrolyzable amino acid biomarkers suggest negligible degradation of terrestrial OC and minor degradation of marine OC. Although a portion of marine OC was prone to remineralization in sediments, it represented only a small fraction of the total OC resulting in high OC transfer (burial) efficiencies of 68-96% within the top 25 cm of sediments. Overall, Icelandic fjords efficiently bury labile marine OC despite oxic water columns.Peer reviewe
Green chemistry-assisted synthesis of metal nanoparticle and fabrication of microstructurally engineered conductive and endurable M0@PEO functional films
Get PDFThe present research reports the synthesis of poly[ethylene oxide]-based composite films (500 μm) containing metal nanoparticles (NPs) [Ag0 (dp ∼ 6 nm), Cu0 (dp ∼ 25 nm), and Fe0 (dp ∼ 35 nm)] as the mobile phase. The novelty of the study is in the corroboration of a plausible mechanism for the generation of metal NPs through green synthesis using herbal extracts of Camellia sinensis (Tea) and Azadirachta indica (Neem). Density functional theory (DFT) is used to optimize the phytoreductants present in both biosources, wherein the reducing and/or stabilizing functional entities are primarily hydroxyl groups (−OH). The transition energy (band gap, ΔE|LUMO–HOMO|) is found to be minimum for Epicatechin gallate (1.05 eV, tea) and Sitosterol (0.58 eV, neem), which could act as potent phytoreductants for initiating a redox reaction, followed by subsequent capping through secondary bond formation. Upon increasing the loading of metal NPs from 1 to 7 wt %, the ionic conductivity of a PEO composite increases (0.1 S·cm–1) for PAgN (N: neem). With a subsequent increase in loading (10 wt %), the crystalline region within PEO is enhanced (≥83% using DSC), which restricts the ion migration and lowers the charge storage capacity, as studied using dielectric constants and complex relaxation processes (EIS and DRT). Among all of the compositions, PCuN is observed to exhibit negligible performance deterioration (Δtan δ for 18,500 h → 0). However, PAg system(s) are good ion conductors with significant dielectric nature, but they suffer from particle ripening. Hence, metal NPs, which functionalize PEO films, could be effectively synthesized using a green synthesis route and applied as a solid electrolyte for device application.Peer reviewe
East of Eden : parallel functional programming in Idris
Get PDFImplicit parallel programming models typically give less control to the programmer over the parallelism properties of the program, but require less specialisedexpertise. Explicit parallel models, on the other hand, give much greater control over the parallelism behaviour, but require much more significant expertisefrom the programmer. In this paper, we introduce a novel semi-implicit parallelmodel for an emerging class of languages known as dependently-typed languages.These dependently-typed languages encourage safer software via their ability toexpress strong logical guarantees, in the form of proofs, directly in code. Oursemi-implicit approach is based on a process model that uses dependent typesto guarantee parallelism properties. We demonstrate how we can use this semi-implicit process model to build common algorithmic skeletons, such as farms,pipelines and divide and conquer skeletons. We evaluate our process skeletonapproach on a number of examples, achieving speedups of up to 21.8 times on a28-core machine.Peer reviewe
Irredundant bases for soluble groups
Get PDFFunding: Sofia Brenner received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (EngageS: grant agreement No. 820148) and from the German Research Foundation DFG (SFB-TRR 195 “Symbolic Tools in Mathematics and their Application” as well as grant 522790373). Coen del Valle is supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), [reference number PGSD-577816-2023], as well as a University of St Andrews School of Mathematics and Statistics Scholarship.Let Δ be a finite set and G be a subgroup of Sym(Δ). An irredundant base for G is a sequence of points of Δ yielding a strictly descending chain of pointwise stabilisers, terminating with the trivial group. Suppose that G is primitive and soluble. We determine asymptotically tight bounds for the maximum length of an irredundant base for G. Moreover, we disprove a conjecture of Seress on the maximum length of an irredundant base constructed by the natural greedy algorithm, and prove Cameron's Greedy Conjecture for |G| odd.Peer reviewe
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