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Dendrochronological methods have been widely used to determine the date of construction and provenance of shipwrecks. Despite a large number of shipwrecks, the application of dendroarchaeological techniques is relatively incipient in the coasts of South America. This paper presents the results of a dendroarchaeological study conducted at the shipwreck site “Bahía Galenses” (BG), located in the western sector of Golfo Nuevo, on the Patagonian coast of the South Atlantic Ocean. Based on previous archaeological research, two hypotheses were tested in this study. First, the wreck described in the BG 2 sub-site corresponds to a mid-19th-century whaler built in the northeastern US. Second, these remains correspond to the Dolphin, a northeastern American whaler built in Warren (Rhode Island) in 1850 and shipwrecked in the Atlantic coast of Patagonia in 1859. Using dendroarchaeological provenance methods and a novel approach based on the gridded North American Drought Atlas, we found highly significant correlations between the wreck's tree-ring width series and white oak and yellow pine tree-ring reference chronologies from the eastern US. The latest non-cutting dates obtained in this analysis correspond to the year 1849. To our knowledge, our study pioneered the use of dendrochronological methods for dating and establishing the provenance of a whaler's remains on the Atlantic coast of South America and encourages the feasibility for future dendroarchaeological research based on the large number of wooden shipwrecks that occurred in the region.

We present UV, optical, and near-infrared (NIR) photometry of the first electromagnetic counterpart to a gravitational wave source from Advanced Laser Interferometer Gravitational-wave Observatory (LIGO)/Virgo, the binary neutron star merger GW170817. Our data set extends from the discovery of the optical counterpart at 0.47-18.5 days post-merger, and includes observations with the Dark Energy Camera (DECam), Gemini-South/FLAMINGOS-2 (GS/F2), and the Hubble Space Telescope (HST). The spectral energy distribution (SED) inferred from this photometry at 0.6 days is well described by a blackbody model with T ≈ 8300 K, a radius of R ≈ 4.5 × 1014cm (corresponding to an expansion velocity of v ≈ 0.3c), and a bolometric luminosity of Lbol ≈ 5 × 1041 erg s-1. At 1.5 days we find a multi-component SED across the optical and NIR, and subsequently we observe rapid fading in the UV and blue optical bands and significant reddening of the optical/NIR colors. Modeling the entire data set, we find that models with heating from radioactive decay of 56Ni, or those with only a single component of opacity from r-process elements, fail to capture the rapid optical decline and red optical/NIR colors. Instead, models with two components consistent with lanthanide-poor and lanthanide-rich ejecta provide a good fit to the data; the resulting "blue" component has Mblueej 0.1 M⊙ and vblueej ≈ 0.3c, and the "red" component has and Mredej ≈ 0.04 M⊙ and vredej ≈ 0.1 c. These ejecta masses are broadly consistent with the estimated r-process production rate required to explain the Milky Way r-process abundances, providing the first evidence that binary neutron star (BNS) mergers can be a dominant site of r-process enrichment.

We present the Dark Energy Camera (DECam) discovery of the optical counterpart of the first binary neutron star merger detected through gravitational-wave emission, GW170817. Our observations commenced 10.5 hr post-merger, as soon as the localization region became accessible from Chile. We imaged 70 deg2 in the i and z bands, covering 93% of the initial integrated localization probability, to a depth necessary to identify likely optical counterparts (e.g., a kilonova). At 11.4 hr post-merger we detected a bright optical transient located from the nucleus of NGC 4993 at redshift z = 0.0098, consistent (for km s-1 Mpc-1) with the distance of 40 ±8 Mpc reported by the LIGO Scientific Collaboration and the Virgo Collaboration (LVC). At detection the transient had magnitudes of and , and thus an absolute magnitude of , in the luminosity range expected for a kilonova. We identified 1500 potential transient candidates. Applying simple selection criteria aimed at rejecting background events such as supernovae, we find the transient associated with NGC 4993 as the only remaining plausible counterpart, and reject chance coincidence at the 99.5% confidence level. We therefore conclude that the optical counterpart we have identified near NGC 4993 is associated with GW170817. This discovery ushers in the era of multi-messenger astronomy with gravitational waves and demonstrates the power of DECam to identify the optical counterparts of gravitational-wave sources.

Climate change is associated with the increase in both the mean and variability of thermal conditions. Therefore, the use of more realistic fluctuating thermal regimes is the most appropriate laboratory method for predicting population responses to thermal heterogeneity. However, the long- and short-term implications of evolving under such conditions are not well understood. Here, we examined differences in key life-history traits among populations of seed beetles (Callosobruchus maculatus) that evolved under either constant control conditions or in an environment with fluctuating daily temperatures. Specifically, individuals from two distinct genetic backgrounds were kept for 19 generations at one of two temperatures, a constant temperature (T = 29 °C) or a fluctuating daily cycle (Tmean = 33 °C, Tmax = 40 °C, and Tmin = 26 °C), and were assayed either in their evolved environment or in the other environment. We found that beetles that evolved in fluctuating environments but were then switched to constant 29 °C conditions had far greater lifetime reproductive success compared with beetles that were kept in their evolved environments. This increase in reproductive success suggests that beetles raised in fluctuating environments may have evolved greater thermal breadth than control condition beetles. In addition, the degree of sexual dimorphism in body size and development varied as a function of genetic background, evolved thermal environment, and current temperature conditions. These results not only highlight the value of incorporating diel fluctuations into climate research but also suggest that populations that experience variability in temperature may be better able to respond to both short- and long-term changes in environmental conditions., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Evolutionary Biology.)

Across western North America (WNA), 20th-21st century anthropogenic warming has increased the prevalence and severity of concurrent drought and heat events, also termed hot droughts. However, the lack of independent spatial reconstructions of both soil moisture and temperature limits the potential to identify these events in the past and to place them in a long-term context. We develop the Western North American Temperature Atlas (WNATA), a data-independent 0.5° gridded reconstruction of summer maximum temperatures back to the 16th century. Our evaluation of the WNATA with existing hydroclimate reconstructions reveals an increasing association between maximum temperature and drought severity in recent decades, relative to the past five centuries. The synthesis of these paleo-reconstructions indicates that the amplification of the modern WNA megadrought by increased temperatures and the frequency and spatial extent of compound hot and dry conditions in the 21st century are likely unprecedented since at least the 16th century.

Extracting data from studies is the norm in meta-analyses, enabling researchers to generate effect sizes when raw data are otherwise not available. While there has been a general push for increased reproducibility in meta-analysis, the transparency and reproducibility of the data extraction phase is still lagging behind. Unfortunately, there is little guidance of how to make this process more transparent and shareable. To address this, we provide several steps to help increase the reproducibility of data extraction in meta-analysis. We also provide suggestions of R software that can further help with reproducible data policies: the shinyDigitise and juicr packages. Adopting the guiding principles listed here and using the appropriate software will provide a more transparent form of data extraction in meta-analyses., (© 2023 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd.)

Code review increases reliability and improves reproducibility of research. As such, code review is an inevitable step in software development and is common in fields such as computer science. However, despite its importance, code review is noticeably lacking in ecology and evolutionary biology. This is problematic as it facilitates the propagation of coding errors and a reduction in reproducibility and reliability of published results. To address this, we provide a detailed commentary on how to effectively review code, how to set up your project to enable this form of review and detail its possible implementation at several stages throughout the research process. This guide serves as a primer for code review, and adoption of the principles and advice here will go a long way in promoting more open, reliable, and transparent ecology and evolutionary biology., (© 2023 The Authors. Journal of Evolutionary Biology published by John Wiley & Sons Ltd on behalf of European Society for Evolutionary Biology.)

Compound earthquakes involving simultaneous ruptures along multiple faults often define a region's upper threshold of maximum magnitude. Yet, the potential for linked faulting remains poorly understood given the infrequency of these events in the historic era. Geological records provide longer perspectives, although temporal uncertainties are too broad to clearly pinpoint single multifault events. Here, we use dendrochronological dating and a cosmogenic radiation pulse to constrain the death dates of earthquake-killed trees along two adjacent fault zones near Seattle, Washington to within a 6-month period between the 923 and 924 CE growing seasons. Our narrow constraints conclusively show linked rupturing that occurred either as a single composite earthquake of estimated magnitude 7.8 or as a closely spaced double earthquake sequence with estimated magnitudes of 7.5 and 7.3. These scenarios, which are not recognized in current hazard models, increase the maximum earthquake size needed for seismic preparedness and engineering design within the Puget Sound region of >4 million residents.

Fasting increases lifespan in invertebrates, improves biomarkers of health in vertebrates and is increasingly proposed as a promising route to improve human health. Nevertheless, little is known about how fasted animals use resources upon refeeding, and how such decisions affect putative trade-offs between somatic growth and repair, reproduction and gamete quality. Such fasting-induced trade-offs are based on strong theoretical foundations and have been recently discovered in invertebrates, but the data on vertebrates are lacking. Here, we report that fasted female zebrafish, Danio rerio , increase investment in soma upon refeeding, but it comes at a cost of egg quality. Specifically, an increase in fin regrowth was accompanied by a reduction in 24 h post-fertilization offspring survival. Refed males showed a reduction in sperm velocity and impaired 24 h post-fertilization offspring survival. These findings underscore the necessity of considering the impact on reproduction when assessing evolutionary and biomedical implications of lifespan-extending treatments in females and males and call for careful evaluation of the effects of intermittent fasting on fertilization.

Recent climate extremes in Mongolia have ignited a renewed interest in understanding past climate variability over centennial and longer time scales across north-central Asia. Tree-ring width records have been extensively studied in Mongolia as proxies for climate reconstruction, however, the climate and environmental signals of tree-ring stable isotopes from this region need to be further explored. Here, we evaluated a 182-year record of tree-ring δ13C and δ18O from Siberian Pine (Pinus sibirica Du Tour) from a xeric site in central Mongolia (Khorgo Lava) to elucidate the environmental factors modulating these parameters. First, we analyzed the climate sensitivity of tree-ring δ13C and δ18O at Khorgo Lava for comparison with ring-width records, which have been instrumental in reconstructing hydroclimate in central Mongolia over two millennia. We also compared stable isotope records of trees with partial cambial dieback ('strip-bark morphology'), a feature of long-lived conifers growing on resource-limited sites, and trees with a full cambium ('whole-bark morphology'), to assess the inferred leaf-level physiological behavior of these trees. We found that interannual variability in tree-ring δ13C and δ18O reflected summer hydroclimatic variability, and captured recent, extreme drought conditions, thereby complementing ring-width records. The tree-ring δ18O records also had a spring temperature signal and thus expanded the window of climate information recorded by these trees. Over longer time scales, strip-bark trees had an increasing trend in ring-widths, δ13C (and intrinsic water-use efficiency, iWUE) and δ18O, relative to whole-bark trees. Our results suggest that increases in iWUE at this site might be related to a combination of leaf-level physiological responses to increasing atmospheric CO2, recent drought, and stem morphological changes. Our study underscores the potential of stable isotopes for broadening our understanding of past climate in north-central Asia. However, further studies are needed to understand how stem morphological changes might impact stable isotopic trends., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Maternal senescence is the reduction in individual performance associated with increased maternal age at conception. When manifested on adult lifespan, this phenomenon is known as the "Lansing Effect." Single-species studies report both maternal age-related increases and decreases in adult lifespan, but no comprehensive review of the literature has yet been undertaken to determine if the Lansing Effect is a widespread phenomenon. To address this knowledge gap, we performed a meta-analysis of maternal aging rates taken from all available published studies. We recovered 78 estimates from 22 studies representing 15 species. All studies taken together suggest a propensity for a Lansing Effect, with an estimated average effect of maternal age on offspring's adult lifespan of between -17% and -22%, depending upon our specific choice of model. We failed to find a significant effect of animal class or insect order but given the oversampling of insect species in the published literature and the paucity of vertebrate studies, we infer that only rotifers and insects yet demonstrate a tendency toward expressing the phenomenon., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE).)

Linked to major volcanic eruptions around 536 and 540 CE, the onset of the Late Antique Little Ice Age has been described as the coldest period of the past two millennia. The exact timing and spatial extent of this exceptional cold phase are, however, still under debate because of the limited resolution and geographical distribution of the available proxy archives. Here, we use 106 wood anatomical thin sections from 23 forest sites and 20 tree species in both hemispheres to search for cell-level fingerprints of ephemeral summer cooling between 530 and 550 CE. After cross-dating and double-staining, we identified 89 Blue Rings (lack of cell wall lignification), nine Frost Rings (cell deformation and collapse), and 93 Light Rings (reduced cell wall thickening) in the Northern Hemisphere. Our network reveals evidence for the strongest temperature depression between mid-July and early-August 536 CE across North America and Eurasia, whereas more localised cold spells occurred in the summers of 532, 540-43, and 548 CE. The lack of anatomical signatures in the austral trees suggests limited incursion of stratospheric volcanic aerosol into the Southern Hemisphere extra-tropics, that any forcing was mitigated by atmosphere-ocean dynamical responses and/or concentrated outside the growing season, or a combination of factors. Our findings demonstrate the advantage of wood anatomical investigations over traditional dendrochronological measurements, provide a benchmark for Earth system models, support cross-disciplinary studies into the entanglements of climate and history, and question the relevance of global climate averages., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2022 Science China Press. Published by Elsevier B.V. All rights reserved.)

Parental age at reproduction influences offspring size and survival by affecting prenatal and postnatal conditions in a wide variety of species, including humans. However, most investigations into this manifestation of ageing focus upon maternal age effects; the effects of paternal age and interactions between maternal and paternal age are often neglected. Furthermore, even when maternal age effects are studied, pre- and post-natal effects are often confounded. Using a cross-fostered experimental design, we investigated the joint effects of pre-natal paternal and maternal and post-natal maternal ages on five traits related to offspring outcomes in a laboratory population of a species of burying beetle, Nicrophorus vespilloides . We found a significant positive effect of the age of the egg producer on larval survival to dispersal. We found more statistical evidence for interaction effects, which acted on larval survival and egg length. Both interaction effects were negative and involved the age of the egg-producer, indicating that age-related pre-natal maternal improvements were mitigated by increasing age in fathers and foster mothers. These results agree with an early study that found little evidence for maternal senescence, but it emphasizes that parental age interactions may be an important contributor to ageing patterns. We discuss how the peculiar life history of this species may promote selection to resist the evolution of parental age effects, and how this might have influenced our ability to detect senescence., (© The Author(s) 2022. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology.)