Ecological diversification of sea catfishes is accompanied by genome-wide signatures of positive selection.

Habitat transitions have shaped the evolutionary trajectory of many clades. Sea catfishes (Ariidae) have repeatedly undergone ecological transitions, including colonizing freshwaters from marine environments, leading to an adaptive radiation in Australia and New Guinea alongside non-radiating freshwater lineages elsewhere. Here, we generate and analyze one long-read reference genome and 66 short-read whole genome assemblies, in conjunction with genomic data for 54 additional species.

Evolutionary Rate Shifts in Coding and Regulatory Regions Underpin Repeated Adaptation to Sulfidic Streams in Poeciliid Fishes.

Adaptation to extreme environments often involves the evolution of dramatic physiological changes. To better understand how organisms evolve these complex phenotypic changes, the repeatability and predictability of evolution, and possible constraints on adapting to an extreme environment, it is important to understand how adaptive variation has evolved. Poeciliid fishes represent a particularly fruitful study system for investigations of adaptation to extreme environments due to their repeated colonization of toxic hydrogen sulfide-rich springs across multiple species within the clade.

Why Do Some Lineages Radiate While Others Do Not? Perspectives for Future Research on Adaptive Radiations.

Understanding the processes that drive phenotypic diversification and underpin speciation is key to elucidating how biodiversity has evolved. Although these processes have been studied across a wide array of clades, adaptive radiations (ARs), which are systems with multiple closely related species and broad phenotypic diversity, have been particularly fruitful for teasing apart the factors that drive and constrain diversification. As such, ARs have become popular candidate study systems for determining the extent to which ecological features, including aspects of organisms and the environment, and inter- and intraspecific interactions, led to evolutionary diversification.

Evolutionary genomics of oceanic island radiations.

A recurring feature of oceanic archipelagos is the presence of adaptive radiations that generate endemic, species-rich clades that can offer outstanding insight into the links between ecology and evolution. Recent developments in evolutionary genomics have contributed towards solving long-standing questions at this interface. Using a comprehensive literature search, we identify studies spanning 19 oceanic archipelagos and 110 putative adaptive radiations, but find that most of these radiations have not yet been investigated from an evolutionary genomics perspective.

Genomic architecture of adaptive radiation and hybridization in Alpine whitefish.

Adaptive radiations represent some of the most remarkable explosions of diversification across the tree of life. However, the constraints to rapid diversification and how they are sometimes overcome, particularly the relative roles of genetic architecture and hybridization, remain unclear. Here, we address these questions in the Alpine whitefish radiation, using a whole-genome dataset that includes multiple individuals of each of the 22 species belonging to six ecologically distinct ecomorph classes across several lake-systems.

Stepwise evolution of a butterfly supergene via duplication and inversion.

Supergenes maintain adaptive clusters of alleles in the face of genetic mixing. Although usually attributed to inversions, supergenes can be complex, and reconstructing the precise processes that led to recombination suppression and their timing is challenging. We investigated the origin of the BC supergene, which controls variation in warning coloration in the African monarch butterfly, .

Genomic variation from an extinct species is retained in the extant radiation following speciation reversal.

Ecosystem degradation and biodiversity loss are major global challenges. When reproductive isolation between species is contingent on the interaction of intrinsic lineage traits with features of the environment, environmental change can weaken reproductive isolation and result in extinction through hybridization. By this process called speciation reversal, extinct species can leave traces in genomes of extant species through introgressive hybridization.

Genome assembly of Danaus chrysippus and comparison with the Monarch Danaus plexippus.

Milkweed butterflies in the genus Danaus are studied in a diverse range of research fields including the neurobiology of migration, biochemistry of plant detoxification, host-parasite interactions, evolution of sex chromosomes, and speciation. We have assembled a nearly chromosomal genome for Danaus chrysippus (known as the African Monarch, African Queen, and Plain Tiger) using long-read sequencing data. This species is of particular interest for the study of genome structural change and its consequences for evolution.

Sequencing platform shifts provide opportunities but pose challenges for combining genomic data sets.

Technological advances in DNA sequencing over the last decade now permit the production and curation of large genomic data sets in an increasing number of nonmodel species. Additionally, these new data provide the opportunity for combining data sets, resulting in larger studies with a broader taxonomic range. Whilst the development of new sequencing platforms has been beneficial, resulting in a higher throughput of data at a lower per-base cost, shifts in sequencing technology can also pose challenges for those wishing to combine new sequencing data with data sequenced on older platforms.

A de novo chromosome-level genome assembly of Coregonus sp. "Balchen": One representative of the Swiss Alpine whitefish radiation.

Salmonids are of particular interest to evolutionary biologists due to their incredible diversity of life-history strategies and the speed at which many salmonid species have diversified. In Switzerland alone, over 30 species of Alpine whitefish from the subfamily Coregoninae have evolved since the last glacial maximum, with species exhibiting a diverse range of morphological and behavioural phenotypes. This, combined with the whole genome duplication which occurred in the ancestor of all salmonids, makes the Alpine whitefish radiation a particularly interesting system in which to study the genetic basis of adaptation and speciation and the impacts of ploidy changes and subsequent rediploidization on genome evolution.

A European Whitefish Linkage Map and Its Implications for Understanding Genome-Wide Synteny Between Salmonids Following Whole Genome Duplication.

Genomic datasets continue to increase in number due to the ease of production for a wider selection of species including non-model organisms. For many of these species, especially those with large or polyploid genomes, highly contiguous and well-annotated genomes are still rare due to the complexity and cost involved in their assembly. As a result, a common starting point for genomic work in non-model species is the production of a linkage map.

Arbuscular mycorrhizal fungi promote coexistence and niche divergence of sympatric palm species on a remote oceanic island.

Microbes can have profound effects on their hosts, driving natural selection, promoting speciation and determining species distributions. However, soil-dwelling microbes are rarely investigated as drivers of evolutionary change in plants. We used metabarcoding and experimental manipulation of soil microbiomes to investigate the impact of soil and root microbes in a well-known case of sympatric speciation, the Howea palms of Lord Howe Island (Australia).

Pleomorphic adenoma arising in an incidental midline isthmic thyroid nodule: a case report and review of the literature.

Ectopic salivary gland tissue is common in the head and neck, usually associated with lymph nodes in lateral areas. It is rarely noted in the thyroid gland. Here we report the first case of a pleomorphic adenoma presenting as a midline nodule in the isthmus of thyroid in a 66-year-old man.

Non-linear relationship between an index of social deprivation, psychiatric admission prevalence and the incidence of psychosis.

Background: Indicators of population socio-economic disadvantage expressed as weighted deprivation indices show strong relationships with mental health and underpin national funding of psychiatric services. A new index of social deprivation, the Mental Illness Needs Index, has been devised specifically to predict need for psychiatric services. Its validity has not been established outside the area in which it was developed.

The relationship of cognitive, personality, and academic measures to anesthesiology resident clinical performance.

Unlabelled: Cognitive skills (including vigilance), personality factors, and standardized academic test performance may be associated with clinical competence in anesthesiology to varying degrees. Sixty-seven anesthesiology residents in training at one center between 1993 and 1995 were administered the modified Vigil (For Thought, Ltd., Nashua, NH), the Paced Auditory Serial Addition Test, the California Personality Inventory, the State-Trait Anxiety Inventory, and five standardized academic performance tests.

Demographic and educational characteristics of inner city middle school problem absence students.

Results of a study of characteristics of middle school students revealed highly significant differences between problem absence students and non-problem absence students on all study variables except sex. Characteristics such as increasing grade, being behind appropriate grade, busing and special education status, and the particular school attended were highly correlated with this behavior, as were race and increasing age.

Endocrine and reproductive dysfunction in men associated with occupational inorganic lead intoxication.

In an attempt to define a postulated effect of lead on male endocrine function, seven men with symptomatic occupational lead intoxication (maximum whole blood lead levels 66-139 micrograms/dl) underwent in-patient endocrine evaluation at the time of diagnosis. Defects in thyroid function, probably of central origin, were present in three patients. Six patients had subnormal glucocorticoid production measured by 24-hr urinary 17-hydroxycorticosteroids and plasma cortisol responses to vasopressin- and/or insulin-induced hypoglycemia.

Depressed thyroid indexes associated with occupational exposure to inorganic lead.

The finding of low values for serum thyroxine and estimated free thyroxine in seven of 12 workers referred because of elevated blood lead levels (greater than 40 mg/L) prompted further investigation. In a cross-sectional study of workers at a small foundry, both measurements were found to regress negatively with blood lead level. In 12 of 47 subjects, both indexes were in the hypothyroid range.

Erythrocyte insulin binding in insulin-dependent diabetes mellitus: lack of relationship to duration and control of diabetes in children and adolescents.

Insulin binding was measured in the erythrocytes (RBCs) of four children and 12 adolescents with insulin-dependent diabetes mellitus in the basal (fasting, nonketotic) state. Children and adolescents with insulin-dependent diabetes mellitus showed normal binding of insulin to their RBCs when expressed as the total insulin bound over the physiologic range of insulin concentrations. The insulin receptor concentration and receptor binding affinity for insulin were also normal.

Increased integrated concentration of norepinephrine, epinephrine, aldosterone, and growth hormone in patients with uncontrolled juvenile diabetes mellitus.

The 24-h integrated plasma concentration of glucose (IC-glucose), norepinephrine (IC-NE), epinephrine (IC-E), cortisol (IC-F), growth hormone (IC-GH), aldosterone (IC-ALDO), and plasma renin activity (IC-PRA) were measured in 11 nonobese juvenile-onset nonketotic diabetic patients exhibiting hyperglycemia and glycosuria and 34 matched control subjects using a portable pump, drawing blood at a constant rate through a nonthrombogenic i.v. catheter.