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Abstract Background In ecosystems influenced by strong seasonal variation in insolation, the fitness of diverse taxa depends on seasonal movements to track resources along latitudinal or elevational gradients. Deep pelagic ecosystems, where sunlight is extremely limited, represent Earth’s largest habitable space and yet ecosystem phenology and effective animal movement strategies in these systems are little understood. Sperm whales (Physeter macrocephalus) provide a valuable acoustic window into this world: the echolocation clicks they produce while foraging in the deep sea are the loudest known biological sounds on Earth and convey detailed information about their behavior. Methods We analyze seven years of continuous passive acoustic observations from the Central California Current System, using automated methods to identify both presence and demographic information from sperm whale echolocation clicks. By integrating empirical results with individual-level movement simulations, we test hypotheses about the movement strategies underlying sperm whales’ long-distance movements in the Northeast Pacific. Results We detect foraging sperm whales of all demographic groups year-round in the Central California Current System, but also identify significant seasonality in frequency of presence. Among several previously hypothesized movement strategies for this population, empirical acoustic observations most closely match simulated results from a population undertaking a “seasonal resource-tracking migration”, in which individuals move to track moderate seasonal-latitudinal variation in resource availability. Discussion Our findings provide evidence for seasonal movements in this cryptic top predator of the deep sea. We posit that these seasonal movements are likely driven by tracking of deep-sea resources, based on several lines of evidence: (1) seasonal-latitudinal patterns in foraging sperm whale detection across the Northeast Pacific; (2) lack of demographic variation in seasonality of presence; and (3) the match between simulations of seasonal resource-tracking migration and empirical results. We show that sperm whales likely track oceanographic seasonality in a manner similar to many surface ocean predators, but with dampened seasonal-latitudinal movement patterns. These findings shed light on the drivers of sperm whales’ long-distance movements and the shrouded phenology of the deep-sea ecosystems in which they forage.

Abstract Social information is predicted to enhance the quality of animals’ migratory decisions in dynamic ecosystems, but the relative benefits of social information in the long-range movements of marine megafauna are unknown. In particular, whether and how migrants use nonlocal information gained through social communication at the large spatial scale of oceanic ecosystems remains unclear. Here we test hypotheses about the cues underlying timing of blue whales’ breeding migration in the Northeast Pacific via individual-based models parameterized by empirical behavioral data. Comparing emergent patterns from individual-based models to individual and population-level empirical metrics of migration timing, we find that individual whales likely rely on both personal and social sources of information about forage availability in deciding when to depart from their vast and dynamic foraging habitat and initiate breeding migration. Empirical patterns of migratory phenology can only be reproduced by models in which individuals use long-distance social information about conspecifics’ behavioral state, which is known to be encoded in the patterning of their widely propagating songs. Further, social communication improves pre-migration seasonal foraging performance by over 60% relative to asocial movement mechanisms. Our results suggest that long-range communication enhances the perceptual ranges of migrating whales beyond that of any individual, resulting in increased foraging performance and more collective migration timing. These findings indicate the value of nonlocal social information in an oceanic migrant and suggest the importance of long-distance acoustic communication in the collective migration of wide-ranging marine megafauna.

Summary: Background: Obesity represents a major global health challenge with important clinical implications. Despite its recognized importance, the global disease burden attributable to high body mass index (BMI) remains less well understood. Methods: We systematically analyzed global deaths and disability-adjusted life years (DALYs) attributable to high BMI using the methodology and analytical approaches of the Global Burden of Disease Study (GBD) 2021. High BMI was defined as a BMI over 25 kg/m2 for individuals aged ≥20 years. The Socio-Demographic Index (SDI) was used as a composite measure to assess the level of socio-economic development across different regions. Subgroup analyses considered age, sex, year, geographical location, and SDI. Findings: From 1990 to 2021, the global deaths and DALYs attributable to high BMI increased more than 2.5-fold for females and males. However, the age-standardized death rates remained stable for females and increased by 15.0% for males. Similarly, the age-standardized DALY rates increased by 21.7% for females and 31.2% for males. In 2021, the six leading causes of high BMI-attributable DALYs were diabetes mellitus, ischemic heart disease, hypertensive heart disease, chronic kidney disease, low back pain and stroke. From 1990 to 2021, low-middle SDI countries exhibited the highest annual percentage changes in age-standardized DALY rates, whereas high SDI countries showed the lowest. Interpretation: The worldwide health burden attributable to high BMI has grown significantly between 1990 and 2021. The increasing global rates of high BMI and the associated disease burden highlight the urgent need for regular surveillance and monitoring of BMI. Funding: National Natural Science Foundation of China and National Key R&D Program of China.

Hepatitis B and Hepatitis C are viral causes of Hepatitis that lead to significant worldwide mortality and morbidity through the sequelae of fibrosis and hepatocellular carcinoma. In this review, we have summarized recent studies that have examined the effects of antiviral therapy on the regression of fibrosis and the reduction in mortalities associated with the viruses. Antiviral therapy significantly decreases mortality and induces the regression of fibrosis.

Distinctive for its pungent and oftentimes rotten odor, the thorny fruit of durian (Durio spp.) is considered a delicacy throughout Asia. Despite its burgeoning global recognition, durian remains a fruit of contradiction—desirable to some yet repulsive to others. Although regarded commonly as immobile, mute, and insentient, plants such as durian communicate within their own bodies, between the same and different species, and between themselves and other life forms. As individuals and collectives, plants develop modes of language—or phytodialects—that are specific to certain contexts. Focused on vegetal semiosis or sign processes, a phytosemiotic lens views plants as dynamic and expressive subjects positioned within lifeworlds. Absent from phytosemiotic theory, however, are the cultural sign processes that take place within and between plants—what I call cultural phytosemiotics. The framework I propose calls attention to the interlinked biological, ecological, and cultural dimensions of signification between plants and non-plants. From a phytosemiotic standpoint, this article examines historical, cinematographic, and literary narratives of durian. Reflecting the fruit’s divisive sensory effects, historical accounts of Durio by Niccolò de’ Conti, Jan Huyghen van Linschoten, Georg Eberhard Rumphius, and William Marsden alternate between praise and disdain. Moreover, films such as Fruit Chan’s Durian Durian (2000) and Anthony Chen’s Wet Season (2019) narrativize the polarities that similarly figure into historical depictions of the species. Literary narratives, including the poems “Durians” (2005) by Hsien Min Toh and “Hurling a Durian” (2013) by Sally Wen Mao, investigate the language of durian’s olfactory and gustatory sensations. Along a continuum between adoration to revulsion, durian embodies the otherness of vegetal being. In an era of rampant biodiversity loss, learning to embrace botanical difference should be a human imperative.