Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany.
Published: February 2022
AI Article Synopsis
Article Abstract
Steller's sea cow, an extinct sirenian and one of the largest Quaternary mammals, was described by Georg Steller in 1741 and eradicated by humans within 27 years. Here, we complement Steller's descriptions with paleogenomic data from 12 individuals. We identified convergent evolution between Steller's sea cow and cetaceans but not extant sirenians, suggesting a role of several genes in adaptation to cold aquatic (or marine) environments. Among these are inactivations of lipoxygenase genes, which in humans and mouse models cause ichthyosis, a skin disease characterized by a thick, hyperkeratotic epidermis that recapitulates Steller's sea cows' reportedly bark-like skin. We also found that Steller's sea cows' abundance was continuously declining for tens of thousands of years before their description, implying that environmental changes also contributed to their extinction.
Laboratório de Biologia Teórica e Matemática Experimental (MetaBIO), Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21941-909, Brazil.
Brain reconstruction, specially of the cerebral cortex, is a challenging task and even more so when it comes to highly gyrified brained animals. Here, we present Stitcher, a novel tool capable of generating such surfaces utilizing MRI data and manual segmentation. Stitcher makes a triangulation between consecutive brain slice segmentations by recursively adding edges that minimize the total length and simultaneously avoid self-intersection.
An evaluation of morbidity and mortality in Steller sea lions (SSLs) Eumetopias jubatus under professional care identified a high prevalence of thyroid disease in aged animals. While studies have investigated the effects of age, season, nutrition, stressors, and pollutants on thyroid hormones in pinnipeds, data from individuals with known thyroid disease are lacking. Histopathological reports of adult SSLs in North American aquariums from 1979 to 2022 with banked serum (n = 14) were reviewed.
To date, published comprehensive pathology investigations documented in Steller sea lions (SSL; ) are from free-ranging populations, whereas health data from those under professional care in aquariums are currently lacking. A retrospective review of gross and histopathologic reports of SSL under human care in North American aquariums from 1979 to 2021 ( = 20) was performed. Associations between age, sex, or birth origin (born in aquariums versus the wild) with cause of death (COD) and comorbidities were explored.
Institute of Northern Engineering, Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK 99775, USA; Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA.
The study analyzes how factors like location, age, diet, and metabolism affect the concentration of essential and non-essential elements in Steller sea lion pups from different Aleutian Islands rookeries.
Differences in element concentrations, like higher mercury in one rookery and higher sulfur in another, were found, indicating locality impacts wildlife health.
The research revealed strong interactions among elements in lanugo, suggesting that these relationships are important for understanding the health and metabolism of sea lion pups.
Institute of Northern Engineering, Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK 99775, USA; Alaska Department of Fish and Game, Division of Wildlife Conservation, Fairbanks, AK 99701, USA. Electronic address:
Steller sea lions (SSL) are sentinels for monitoring environmental contaminants in remote areas of the Aleutian Islands, Alaska. Therefore, concentrations of several organochlorines (OCs) were measured in blood from 123 SSL pups sampled from 3 regions; the western Aleutian Islands (WAI), central Aleutian Islands (CAI), and the central Gulf of Alaska. Blood, blubber, and milk from 12 adult female SSL from WAI, CAI and southeast Alaska also were analyzed.
