Meta-analysis shows no consistent evidence for senescence in ejaculate traits across animals.

Male reproductive traits such as ejaculate size and quality, are expected to decline with advancing age due to senescence. It is however unclear whether this expectation is upheld across taxa. We perform a meta-analysis on 379 studies, to quantify the effects of advancing male age on ejaculate traits across 157 species of non-human animals. Contrary to predictions, we find no consistent pattern of age-dependent changes in ejaculate traits. This result partly reflects methodological limitations, such as studies sampling a low proportion of adult lifespan, or the inability of meta-analytical approaches to document non-linear ageing trajectories of ejaculate traits; which could potentially lead to an underestimation of senescence. Yet, we find taxon-specific differences in patterns of ejaculate senescence. For instance, older males produce less motile and slower sperm in ray-finned fishes, but larger ejaculates in insects, compared to younger males. Notably, lab rodents show senescence in most ejaculate traits measured. Our study challenges the notion of universal reproductive senescence, highlighting the need for controlled methodologies and a more nuanced understanding of reproductive senescence, cognisant of taxon-specific biology, experimental design, selection pressures, and life-history.

Seasonal weather impacts wine quality in Bordeaux.

Critics judge quality based upon subjective characteristics of wine. These judgments are converted by critics into quantitative scores, which allow for comparison of vintages. This paper uses high resolution discrete and continuous time-based weather estimates at both a local and regional level to determine the role of weather conditions on producing high quality Bordeaux vintages, as determined by critics scores. By using discrete-time weather variables across local AOCs, this study reveals climate-quality relationships across the whole year, including previously ignored season effects. By using continuous time weather variables, we reinforce the evidence for these local effects by finding higher quality wine is made in years with higher rainfall, warmer temperatures; and earlier, shorter seasons. We propose management impacts of our results and suggest that as the climate continues to change, the quality of Bordeaux wines may continue to improve.

MOSAIC - A Unified Trait Database to Complement Structured Population Models.

Despite exponential growth in ecological data availability, broader interoperability amongst datasets is needed to unlock the potential of open access. Our understanding of the interface of demography and functional traits is well-positioned to benefit from such interoperability. Here, we introduce MOSAIC, an open-access trait database that unlocks the demographic potential stored in the COMADRE, COMPADRE, and PADRINO open-access databases. MOSAIC data were digitised and curated through a combination of existing datasets and new trait records sourced from primary literature. In its first release, MOSAIC (v. 1.0.0) includes 14 trait fields for 300 animal and plant species: biomass, height, growth determination, regeneration, sexual dimorphism, mating system, hermaphrodism, sequential hermaphrodism, dispersal capacity, type of dispersal, mode of dispersal, dispersal classes, volancy, and aquatic habitat dependency. MOSAIC includes species-level phylogenies for 1,359 species and population-specific climate data. We identify how database integration can improve our understanding of traits well-quantified in existing repositories and those that are poorly quantified (e.g., growth determination, modularity). MOSAIC highlights emerging challenges associated with standardising databases and demographic measures.

Plasticity's role in adaptive evolution depends on environmental change components.

To forecast extinction risks of natural populations under climate change and direct human impacts, an integrative understanding of both phenotypic plasticity and adaptive evolution is essential. To date, the evidence for whether, when, and how much plasticity facilitates adaptive responses in changing environments is contradictory. We argue that explicitly considering three key environmental change components - rate of change, variance, and temporal autocorrelation - affords a unifying framework of the impact of plasticity on adaptive evolution. These environmental components each distinctively effect evolutionary and ecological processes underpinning population viability. Using this framework, we develop expectations regarding the interplay between plasticity and adaptive evolution in natural populations. This framework has the potential to improve predictions of population viability in a changing world.

The steroid hormone ecdysone regulates growth rate in response to oxygen availability.

In almost all animals, physiologically low oxygen (hypoxia) during development slows growth and reduces adult body size. The developmental mechanisms that determine growth under hypoxic conditions are, however, poorly understood. Here we show that the growth and body size response to moderate hypoxia (10% O2) in Drosophila melanogaster is systemically regulated via the steroid hormone ecdysone. Hypoxia increases level of circulating ecdysone and inhibition of ecdysone synthesis ameliorates the negative effect of low oxygen on growth. We also show that the effect of ecdysone on growth under hypoxia is through suppression of the insulin/IGF-signaling pathway, via increased expression of the insulin-binding protein Imp-L2. These data indicate that growth suppression in hypoxic Drosophila larvae is accomplished by a systemic endocrine mechanism that overlaps with the mechanism that slows growth at low nutrition. This suggests the existence of growth-regulatory mechanisms that respond to general environmental perturbation rather than individual environmental factors.

Larval Density, Sex, and Allocation Hierarchy Affect Life History Trait Covariances in a Bean Beetle.

AbstractLife history theory aims to understand how different environments result in differential investment in fitness-related traits. While trade-offs between traits are expected, many studies show positive or no correlation between pairs of costly traits. One hypothesis that may explain the inconsistency of trade-offs in the literature is that trait investment may occur in a dichotomous hierarchy (the tree model), which allows for differential trait investment weighted by the traits' respective positions within the hierarchy. Previous mathematical models predict different covariances between traits depending on their position on the allocation tree. While hierarchical differential investment is often used to discuss findings in life history theory, the role of an allocation hierarchy in trait covariances has not been directly tested. In turn, this study aims to identify trait covariances between behavioral and morphological phenotypes on different branches of an allocation tree for the bean beetle, Callosobruchus maculatus. While trade-offs between copulatory behaviors and morphology were found for both males and females, only traits at the base and far from each other in the hierarchy negatively covaried. This study empirically shows that trade-offs may be the result of hierarchical investment.

Four key challenges in the open-data revolution.

In Focus: Culina, A., Adriaensen, F., Bailey, L. D., et al. (2021) Connecting the data landscape of long-term ecological studies: The SPI-Birds data hub. Journal of Animal Ecology, https://doi.org/10.1111/1365-2656.13388. Long-term, individual-based datasets have been at the core of many key discoveries in ecology, and calls for the collection, curation and release of these kinds of ecological data are contributing to a flourishing open-data revolution in ecology. Birds, in particular, have been the focus of international research for decades, resulting in a number of uniquely long-term studies, but accessing these datasets has been historically challenging. Culina et al. (2021) introduce an online repository of individual-level, long-term bird records with ancillary data (e.g. genetics), which will enable key ecological questions to be answered on a global scale. As well as these opportunities, however, we argue that the ongoing open-data revolution comes with four key challenges relating to the (1) harmonisation of, (2) biases in, (3) expertise in and (4) communication of, open ecological data. Here, we discuss these challenges and how key efforts such as those by Culina et al. are using FAIR (Findable, Accessible, Interoperable and Reproducible) principles to overcome them. The open-data revolution will undoubtedly reshape our understanding of ecology, but with it the ecological community has a responsibility to ensure this revolution is ethical and effective.

Enfocado: Culina, A., Adriaensen, F., Bailey, L. D., et al. (2021) Connecting the data landscape of long-term ecological studies: the SPI-Birds data hub. Journal of Animal Ecology, https://doi.org/10.1111/1365-2656.13388. La información a largo plazo y a nivel de individuo ha cementado numerosos descubrimientos clave en la ecología, y las llamadas para la recopilación, conservación, y publicación de este tipo de datos ecológicos están contribuyendo a una revolución de información abierta en la ecología. Las aves, en particular, han sido el foco de la investigación internacional durante décadas, el cual ha resultado en una serie de estudios únicos a largo plazo. No obstante, historicamente el acceso libre a esta información ha representado un desafío importante. Culina y colegas (2021) presentan un repositorio online de registros de aves a nivel individual y de alta replicación temporal con metadatos (por ejemplo, genética) que permitirá explorar importantes preguntas ecológicas a grandes escalas espaciales. Sin embargo, además de las oportunidades presentadas en esta base de datos, argumentamos que la revolución de la información abierta viene con cuatro desafíos clave relacionados con (1) la armonización de, (2) los sesgos en, (3) la experiencia en y (4) la comunicación de información ecológica de forma abierta y transparente. Aquí discutimos estos desafíos y cómo esfuerzos clave como los de Culina y colaboradores están utilizando los principios FAIR (por sus siglas en inglés: Localizable, Accesible, Interoperable y Reproducible) para superarlos. La revolución de la información abierta sin duda remodelará nuestro entendimiento de la ecología. Sin embargo, la comunidad ecológica tiene la responsabilidad de garantizar que esta revolución sea ética y eficaz.

Plasticity Through Canalization: The Contrasting Effect of Temperature on Trait Size and Growth in Drosophila.

In most ectotherms, a reduction in developmental temperature leads to an increase in body size, a phenomenon known as the temperature size rule (TSR). In Drosophila melanogaster, temperature affects body size primarily by affecting critical size, the point in development when larvae initiate the hormonal cascade that stops growth and starts metamorphosis. However, while the thermal plasticity of critical size can explain the effect of temperature on overall body size, it cannot entirely account for the effect of temperature on the size of individual traits, which vary in their thermal sensitivity. Specifically, the legs and male genitalia show reduced thermal plasticity for size, while the wings show elevated thermal plasticity, relative to overall body size. Here, we show that these differences in thermal plasticity among traits reflect, in part, differences in the effect of temperature on the rates of cell proliferation during trait growth. Counterintuitively, the elevated thermal plasticity of the wings is due to canalization in the rate of cell proliferation across temperatures. The opposite is true for the legs. These data reveal that environmental canalization at one level of organization may explain plasticity at another, and vice versa.

Algal Bloom Expansion Increases Cyanotoxin Risk in Food.

As advances in global transportation infrastructure make it possible for out of season foods to be available year-round, the need for assessing the risks associated with the food production and expanded distribution are even more important. Risks for foodborne illness are associated with contamination by bacteria, viruses, mold, parasites, natural and synthetic toxins, chemical residues, and conditions that lead to contamination. An increase in the popularity of natural alternatives to pharmaceuticals, herbal remedies and the desire for consuming "super foods" is leading to a change in the dietary patterns of consumers. Similarly, dietary trends are plentiful, with more consumers adopting changes with little medical guidance to dietary plans that are supported by inadequate scientific data. In particular, U.S. consumers are acquiring novel foods that may not be adequately checked for the presence of marine toxins and heat stable toxins in dry or minimally processed foods. Some dry foods cultivated in or processed in regions that may utilize hypoxic agricultural waters high in cyanobacterial or algal contamination. These may perpetuate increased risks for chronic liver, kidney, and neurodegenerative disorders due to intoxication from preventable foodborne agents. Global climate change, which has the effect of potentially expanding the toxic waters into higher latitudes, forecasts an increase in the risk of food contamination with toxins.