Genomic SNPs resolve the phylogeny of an ancient amphibian island radiation from the Seychelles.

Unusually for oceanic islands, the granitic Seychelles host multiple lineages of endemic amphibians. This includes an ancient (likely ca. 60 million years) radiation of eight caecilian species, most of which occur on multiple islands.These caecilians have a complicated taxonomic history and their phylogenetic inter-species relationships have been difficult to resolve. Double-digest RAD sequencing (ddRADseq) has been applied extensively to phylogeography and increasingly to phylogenetics but its utility for resolving ancient divergences is less well established. To address this, we applied ddRADseq to generate a genome-wide SNP panel for phylogenomic analyses of the Seychelles caecilians, whose phylogeny has so far not been satisfactorily resolved with traditional DNA markers. Based on 129,154 SNPs, we resolved deep and shallow splits, with strong support. Our findings demonstrate the capability of genome-wide SNPs for evolutionary inference at multiple taxonomic levels and support the recently proposed synonymy of Grandisonia Taylor, 1968 with Hypogeophis Peters, 1879. We revealed three clades of Hypogeophis (large-, medium- and short-bodied) and identify a single origin of the diminutive, stocky-bodied and pointy-snouted phenotype.

Exceptional levels of species discovery ameliorate inferences of the biogeography and diversification of an Afrotropical catfish family.

Endeavours in species discovery, particularly the characterisation of cryptic species, have been greatly aided by the application of DNA molecular sequence data to phylogenetic reconstruction and inference of evolutionary and biogeographic processes. However, the extent of cryptic and undescribed diversity remains unclear in tropical freshwaters, where biodiversity is declining at alarming rates. To investigate how data on previously undiscovered biodiversity impacts inferences of biogeography and diversification dynamics, we generated a densely sampled species-level family tree of Afrotropical Mochokidae catfishes (220 valid species) that was ca. 70 % complete. This was achieved through extensive continental sampling specifically targeting the genus Chiloglanis a specialist of the relatively unexplored fast-flowing lotic habitat. Applying multiple species-delimitation methods, we report exceptional levels of species discovery for a vertebrate genus, conservatively delimiting a staggering ca. 50 putative new Chiloglanis species, resulting in a near 80 % increase in species richness for the genus. Biogeographic reconstructions of the family identified the Congo Basin as a critical region in the generation of mochokid diversity, and further revealed complex scenarios for the build-up of continental assemblages of the two most species rich mochokid genera, Synodontis and Chiloglanis. While Syndontis showed most divergence events within freshwater ecoregions consistent with largely in situ diversification, Chiloglanis showed much less aggregation of freshwater ecoregions, suggesting dispersal as a key diversification process in this older group. Despite the significant increase in mochokid diversity identified here, diversification rates were best supported by a constant rate model consistent with patterns in many other tropical continental radiations. While our findings highlight fast-flowing lotic freshwaters as potential hotspots for undescribed and cryptic species diversity, a third of all freshwater fishes are currently threatened with extinction, signifying an urgent need to increase exploration of tropical freshwaters to better characterise and conserve its biodiversity.

A near-complete species-level phylogeny of uropeltid snakes harnessing historical museum collections as a DNA source.

Uropeltidae is a clade of small fossorial snakes (ca. 64 extant species) endemic to peninsular India and Sri Lanka. Uropeltid taxonomy has been confusing, and the status of some species has not been revised for over a century. Attempts to revise uropeltid systematics and undertake evolutionary studies have been hampered by incompletely sampled and incompletely resolved phylogenies. To address this issue, we take advantage of historical museum collections, including type specimens, and apply genome-wide shotgun (GWS) sequencing, along with recent field sampling (using Sanger sequencing) to establish a near-complete multilocus species-level phylogeny (ca. 87% complete at species level). This results in a phylogeny that supports the monophyly of all genera (if Brachyophidium is considered a junior synonym of Teretrurus), and provides a firm platform for future taxonomic revision. Sri Lankan uropeltids are probably monophyletic, indicating a single colonisation event of this island from Indian ancestors. However, the position of Rhinophis goweri (endemic to Eastern Ghats, southern India) is unclear and warrants further investigation, and evidence that it may nest within the Sri Lankan radiation indicates a possible recolonisation event. DNA sequence data and morphology suggest that currently recognised uropeltid species diversity is substantially underestimated. Our study highlights the benefits of integrating museum collections in molecular genetic analyses and their role in understanding the systematics and evolutionary history of understudied organismal groups.

Interventions for preventing and ameliorating cognitive deficits in adults treated with cranial irradiation.

BACKGROUND: Cognitive deficits are common in people who have received cranial irradiation and have a serious impact on daily functioning and quality of life. The benefit of pharmacological and non-pharmacological treatment of cognitive deficits in this population is unclear. This is an updated version of the original Cochrane Review published in Issue 12, 2014. OBJECTIVES: To assess the effectiveness of interventions for preventing or ameliorating cognitive deficits in adults treated with cranial irradiation. SEARCH METHODS: For this review update we searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE via Ovid, Embase via Ovid, and PsycInfo via Ovid to 12 September 2022. SELECTION CRITERIA: We included randomised controlled (RCTs) trials that evaluated pharmacological or non-pharmacological interventions in cranial irradiated adults, with objective cognitive functioning as a primary or secondary outcome measure. DATA COLLECTION AND ANALYSIS: Two review authors (MK, JD) independently extracted data from selected studies and carried out a risk of bias assessment. Cognitive function, fatigue and mood outcomes were reported. No data were pooled. MAIN RESULTS: Eight studies met the inclusion criteria and were included in this updated review. Six were from the original version of the review, and two more were added when the search was updated. Nineteen further studies were assessed as part of this update but did not fulfil the inclusion criteria. Of the eight included studies, four studies investigated "prevention" of cognitive problems (during radiotherapy and follow-up) and four studies investigated "amelioration" (interventions to treat cognitive impairment as a late complication of radiotherapy). There were five pharmacological studies (two studies on prevention and three in amelioration) and three non-pharmacological studies (two on prevention and one in amelioration). Due to differences between studies in the interventions being evaluated, a meta-analysis was not possible.  Studies in early radiotherapy treatment phase (five studies) Pharmacological studies in the "early radiotherapy treatment phase" were designed to prevent or ameliorate cognitive deficits and included drugs used in dementia (memantine) and fatigue (d-threo-methylphenidate hydrochloride). Non-pharmacological studies in the "early radiotherapy treatment phase" included a ketogenic diet and a two-week cognitive rehabilitation and problem-solving programme.  In the memantine study, the primary cognitive outcome of memory at six months did not reach significance, but there was significant improvement in overall cognitive function compared to placebo, with similar adverse events across groups. The d-threo-methylphenidate hydrochloride study found no statistically significant difference between arms, with few adverse events. The study of a calorie-restricted ketogenic diet found no effect, although a lower than expected calorie intake in the control group complicates interpretation of the results.  The study investigating the utility of a rehabilitation program did not carry out a statistical comparison of cognitive performance between groups.  Studies in delayed radiation or late effect phase (four studies) The "amelioration" pharmacological studies to treat cognitive complications of radiotherapy included drugs used in dementia (donepezil) or psychostimulants (methylphenidate and modafinil). Non-pharmacological measures included cognitive rehabilitation and problem solving (Goal Management Training). These studies included patients with cognitive problems at entry who had "stable" brain cancer.  The donepezil study did not find an improvement in the primary cognitive outcome of overall cognitive performance, but did find improvement in an individual test of memory, compared to placebo; adverse events were not reported. A study comparing methylphenidate with modafinil found improvements in cognitive function in both the methylphenidate and modafinil arms; few adverse events were reported. Another  study comparing two different doses of modafinil combined treatment arms and found improvements across all cognitive tests, however, a number of adverse events were reported. Both studies were limited by a small sample size. The Goal Management Training study suggested a benefit of the intervention, a behavioural intervention that combined mindfulness and strategy training, on executive function and processing speed.  There were a number of limitations across studies and few were without high risks of bias. AUTHORS' CONCLUSIONS: In this update, limited additional evidence was found for the treatment or amelioration of cognitive deficits in adults treated with cranial irradiation. As concluded in the original review, there is supportive evidence that memantine may help prevent cognitive deficits for adults with brain metastases receiving cranial irradiation. There is supportive evidence that donepezil, methylphenidate and modafinil may have a role in treating cognitive deficits in adults with brain tumours who have been treated with cranial irradiation; patient withdrawal affected the statistical power of these studies. Further research that tries to minimise the withdrawal of consent, and subsequently reduce the requirement for imputation procedures, may offer a higher certainty of evidence. There is evidence from only a single small study to support non-pharmacological interventions in the amelioration of cognitive deficits. Further research is required.

Interventions for the management of fatigue in adults with a primary brain tumour.

BACKGROUND: Fatigue is a common and disabling symptom in people with a primary brain tumour (PBT). The effectiveness of interventions for treating clinically significant levels of fatigue in this population is unclear. This is an updated version of the original Cochrane Review published in Issue 4, 2016. OBJECTIVES: To assess the effectiveness and safety of pharmacological and non-pharmacological interventions for adults with PBT and clinically significant (or high levels) of fatigue. SEARCH METHODS: For this updated review, we searched CENTRAL, MEDLINE and Embase, and checked the reference lists of included studies in April 2022. We also searched relevant conference proceedings, and ClinicalTrials.gov for ongoing trials. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that investigated any pharmacological or non-pharmacological intervention in adults with PBT and fatigue, where fatigue was the primary outcome measure. We restricted inclusion specifically to studies that enrolled only participants with clinically significant levels of fatigue to improve the clinical utility of the findings. DATA COLLECTION AND ANALYSIS: Two review authors (JD, DC) independently evaluated search results for the updated search. Two review authors (JD, SYK) extracted data from selected studies, and carried out a risk of bias assessment. We extracted data on fatigue, mood, cognition, quality of life and adverse events outcomes. MAIN RESULTS: The original review identified one study and this update identified a further two for inclusion. One study investigated the use of modafinil, one study the use of armodafinil and one study the use of dexamfetamine. We identified three ongoing studies. In the original review, the single eligible trial compared modafinil to placebo for 37 participants with a high- or low-grade PBT. One new study compared two doses of armodafinil (150 mg and 250 mg) to placebo for 297 people with a high-grade glioma. The second new study compared dexamfetamine sulfate to placebo for 46 participants with a low- or high-grade PBT. The evidence was uncertain for both modafinil and dexamfetamine regarding fatigue outcome measures, compared to controls, at study endpoint. Two trials did not reach the planned recruitment target and therefore may not, in practice, have been adequately powered to detect a difference. These trials were at a low risk of bias across most areas. There was an unclear risk of bias related to the use of mean imputation for one study because the investigators did not analyse the impact of imputation on the results and information regarding baseline characteristics and randomisation were not clear. The certainty of the evidence measured using GRADE was very low across all three studies. There was one identified study awaiting classification once data are available, which investigated the feasibility of 'health coaching' for people with a PBT experiencing fatigue. There were three ongoing studies that may be eligible for an update of this review, all investigating a non-pharmacological intervention for fatigue in people with PBT. AUTHORS' CONCLUSIONS: There is currently insufficient evidence to draw reliable and generalisable conclusions regarding potential effectiveness or harm of any pharmacological or non-pharmacological treatments for fatigue in people with PBT. More research is needed on how best to treat people with brain tumours with high fatigue.

Molecular phylogenetics of sub-Saharan African natricine snakes, and the biogeographic origins of the Seychelles endemic Lycognathophis seychellensis.

Phylogenetic relationships of sub-Saharan African natricine snakes are understudied and poorly understood, which in turn has precluded analyses of the historical biogeography of the Seychelles endemic Lycognathophis seychellensis. We inferred the phylogenetic relationships of Seychelles and mainland sub-Saharan natricines by analysing a multilocus DNA sequence dataset for three mitochondrial (mt) and four nuclear (nu) genes. The mainland sub-Saharan natricines and L. seychellensis comprise a well-supported clade. Two maximally supported sets of relationships within this clade are (Limnophis,Natriciteres) and (Afronatrix,(Hydraethiops,Helophis)). The relationships of L. seychellensis with respect to these two lineages are not clearly resolved by analysing concatenated mt and nu data. Analysed separately, nu data best support a sister relationship of L. seychellensis with (Afronatrix,(Hydraethiops,Helophis)) and mt data best support a sister relationship with all mainland sub-Saharan natricines. Methods designed to cope with incomplete lineage sorting strongly favour the former hypothesis. Genetic variation among up to 33 L. seychellensis from five Seychelles islands is low. Fossil calibrated divergence time estimates support an overseas dispersal of the L. seychellensis lineage to the Seychelles from mainland Africa ca. 43-25 million years before present (Ma), rather than this taxon being a Gondwanan relic.

Akt Phosphorylates NQO1 and Triggers its Degradation, Abolishing Its Antioxidative Activities in Parkinson's Disease.

The oxidative metabolism of dopamine and consequent oxidative stress are implicated in dopaminergic neuronal loss, mediating the pathogenesis of Parkinson's disease (PD). The inducible detoxifying antioxidative enzyme Quinone oxidoreductase (NQO1) (NAD(P)H: quinone oxidoreductase 1), neuroprotective to counteract reactive oxidative species, is most prominent in the active stage of the disease and virtually absent at the end stage of the disease. However, the molecular mechanism dictating NQO1 expression oscillation remains unclear. Here we show that Akt phosphorylates NQO1 at T128 residues and triggers its polyubiquitination and proteasomal degradation, abrogating its antioxidative effects in PD. Akt binds NQO1 in a phosphorylation-dependent manner. Interestingly, Akt, but not PINK1, provokes NQO1 phosphorylation and polyubiquitination with Parkin as an E3 ligase. Unphosphorylatable NQO1 mutant displays more robust neuroprotective activity than WT NQO1 in suppressing reactive oxidative species and against MPTP-induced dopaminergic cell death, rescuing the motor disorders in both α-synuclein transgenic transgenic male and female mice elicited by the neurotoxin. Thus, our findings demonstrate that blockade of Akt-mediated NQO1 degradation may ameliorate PD pathogenesis.SIGNIFICANCE STATEMENT Dopaminergic neurodegeneration in Parkinson's disease (PD) is associated with the imbalance of oxidative metabolism of dopamine. Quinone oxidoreductase (NQO1), a potent antioxidant system, its expression levels are prominently increased in the early and intermediate stages of PD and disappeared in the end-stage PD. The molecular modification behavior of NQO1 after it is upregulated by oxidative stress in the early stage of PD, however, remains unclear. This study shows that Akt binds and phosphorylates NQO1 at T128 residue and promotes its ubiquitination and degradation, and Parkin acts as an E3 ligase in this process, which affects the antioxidant capacity of NQO1. This finding provides a novel molecular mechanism for NQO1 oscillation in PD pathogenesis.

The roles of vicariance and isolation by distance in shaping biotic diversification across an ancient archipelago: evidence from a Seychelles caecilian amphibian.

BACKGROUND: Island systems offer excellent opportunities for studying the evolutionary histories of species by virtue of their restricted size and easily identifiable barriers to gene flow. However, most studies investigating evolutionary patterns and processes shaping biotic diversification have focused on more recent (emergent) rather than ancient oceanic archipelagos. Here, we focus on the granitic islands of the Seychelles, which are unusual among island systems because they have been isolated for a long time and are home to a monophyletic radiation of caecilian amphibians that has been separated from its extant sister lineage for ca. 65-62 Ma. We selected the most widespread Seychelles caecilian species, Hypogeophis rostratus, to investigate intraspecific morphological and genetic (mitochondrial and nuclear) variation across the archipelago (782 samples from nine islands) to identify patterns and test processes that shaped their evolutionary history within the Seychelles. RESULTS: Overall a signal of strong geographic structuring with distinct northern- and southern-island clusters were identified across all datasets. We suggest that these distinct groups have been isolated for ca. 1.26 Ma years without subsequent migration between them. Populations from the somewhat geographically isolated island of Frégate showed contrasting relationships to other islands based on genetic and morphological data, clustering alternatively with northern-island (genetic) and southern-island (morphological) populations. CONCLUSIONS: Although variation in H. rostratus across the Seychelles is explained more by isolation-by-distance than by adaptation, the genetic-morphological incongruence for affinities of Frégate H. rostratus might be caused by local adaptation over-riding the signal from their vicariant history. Our findings highlight the need of integrative approaches to investigate fine-scale geographic structuring to uncover underlying diversity and to better understand evolutionary processes on ancient, continental islands.

The toad's warts: Discordance creates bumpy expectations of mitochondrial-nuclear evolution between species.

Discordance between the mitochondrial and nuclear genomes is a prevalent phenomenon in nature, in which the underlying processes responsible are considered to be important in shaping genetic variation in natural populations. Among the evolutionary processes that best explain such genomic mismatches incomplete lineage sorting and introgression are commonly identified, however, many studies are unable to distinguish between these hypotheses, which has become a major challenge in the field. In this issue of Molecular Ecology, Firneno et al. (2020) present an elegant exploration of mitochondrial-nuclear discordance in Mesoamerican toads. Integrating genome-scale and spatial data to test between these hypotheses within an empirical model testing framework, they find strong support that incomplete lineage sorting explains the observed discordance. Their work, along with many previous articles in Molecular Ecology, highlights the commonality of mito-nuclear discordance among species despite the expectations of tightly concerted mitochondrial and nuclear genome evolution. It is increasingly clear that the nuclear genomes of many species are (at least for short periods of evolutionary time) functionally compatible with multiple, divergent mitochondrial haplotypes. As such, we suggest future research not only seeks to understand the processes causing spatial mito-nuclear discordance (e.g. incomplete lineage sorting, introgression), but also explores those that maintain discordance through time and space (e.g. relaxed selection on mito-nuclear interactions, heterozygosity, population demographics). We also discuss the vital role that taxonomy plays in interpreting patterns of mito-nuclear discordance when data-consistent yet differing taxonomies are used, such as treating allopatrically distributed taxa as multiple isolated populations versus multiple micro-endemic species.

A comprehensive molecular phylogeny of Afrotropical white-eyes (Aves: Zosteropidae) highlights prior underestimation of mainland diversity and complex colonisation history.

White-eyes (Zosterops) are a hyper-diverse genus of passerine birds that have rapidly radiated across the Afrotropics and Southeast Asia. Despite their broad range, a disproportionately large number of species are currently recognised from islands compared to the mainland. Described species-level diversity of this 'great speciator' from continental Africa-Arabia is strikingly low, despite the vast size and environmental complexity of this region. However, efforts to identify natural groups using traditional approaches have been hindered by the remarkably uniform morphology and plumage of these birds. Here, we investigated the phylogenetic relationships and systematics of Afrotropical Zosterops, including the Gulf of Guinea and western Indian Ocean islands. We included exceptional sampling (~160 individuals) from all except one subspecies of the 55 taxa (32 species, plus 23 additional named sub-species) currently recognized throughout the region, in addition to a subset of extra-Afrotropical taxa, by exploiting blood and archival samples. Employing a multi-locus phylogenetic approach and applying quantitative species delimitation we tested: (1) if there has been a single colonisation event of the Afrotropical realm; (2) if constituent mainland and island birds are monophyletic; and (3) if mainland diversity has been underestimated. Our comprehensive regional phylogeny revealed a single recent colonisation of the Afrotropical realm c.1.30 Ma from Asia, but a subsequent complex colonisation history between constituent island and mainland lineages during their radiation across this vast area. Our findings suggest a significant previous underestimation of continental species diversity and, based on this, we propose a revised taxonomy. Our study highlights the need to densely sample species diversity across ranges, providing key findings for future conservation assessments and establishing a robust framework for evolutionary studies.

Molecular phylogeny of Oreochromis (Cichlidae: Oreochromini) reveals mito-nuclear discordance and multiple colonisation of adverse aquatic environments.

Although the majority of cichlid diversity occurs in the African Great Lakes, these fish have also diversified across the African continent. Such continental radiations, occurring in both rivers and lakes have received far less attention than lacustrine radiations despite some members, such as the oreochromine cichlids (commonly referred to as 'tilapia'), having significant scientific and socio-economic importance both within and beyond their native range. Unique among cichlids, several species of the genus Oreochromis exhibit adaptation to soda conditions (including tolerance to elevated temperatures and salinity), which are of interest from evolutionary biology research and aquaculture perspectives. Questions remain regarding the factors facilitating the diversification of this group, which to date have not been addressed within a phylogenetic framework. Here we present the first comprehensive (32/37 described species) multi-marker molecular phylogeny of Oreochromis and closely related Alcolapia, based on mitochondrial (1583 bp) and nuclear (3092 bp) sequence data. We show widespread discordance between nuclear DNA and mitochondrial DNA trees. This could be the result of incomplete lineage sorting and/or introgression in mitochondrial loci, although we did not find a strong signal for the latter. Based on our nuclear phylogeny we demonstrate that adaptation to adverse conditions (elevated salinity, temperature, or alkalinity) has occurred multiple times within Oreochromis, but that adaptation to extreme (soda) conditions (high salinity, temperature, and alkalinity) has likely arisen once in the lineage leading to O. amphimelas and Alcolapia. We also show Alcolapia is nested within Oreochromis, which is in agreement with previous studies, and here revise the taxonomy to synonymise the genus in Oreochromis, retaining the designation as subgenus Oreochromis (Alcolapia).

Interventions for the management of fatigue in adults with a primary brain tumour.

BACKGROUND: Fatigue is a common and disabling symptom in people with a primary brain tumour (PBT). The effectiveness of interventions for treating clinically significant levels of fatigue in this population is unclear. OBJECTIVES: To assess the effectiveness and safety of pharmacological and non-pharmacological interventions for adults with PBT and high levels of fatigue. SEARCH METHODS: In March 2016, we searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO and CINAHL and checked the reference lists of included studies. We also searched relevant conference proceedings, searched for ongoing trials via ClinicalTrials.gov and contacted major co-operative groups with trials in this area. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that investigated any pharmacological or non-pharmacological intervention in adults with PBT and fatigue, where fatigue was the primary outcome measure. We restricted inclusion specifically to studies that enrolled only participants with clinically significant levels of fatigue. DATA COLLECTION AND ANALYSIS: Three review authors (JD, SYK, DC) independently evaluated search results, extracted data from selected studies and carried out a bias risk assessment. We extracted data on fatigue, cognition, mood, quality of life and adverse events outcomes. MAIN RESULTS: We identified nine studies. We excluded eight of these as they did not restrict participation to people with high fatigue. The single eligible trial investigated the use of modafinil compared to placebo. Although this study found a significant improvement over time in the primary outcome of fatigue, the improvement occurred after both modafinil and placebo with no significant difference in response between the two groups. The included trial did not reach its planned recruitment target and therefore may not, in practice, have been adequately powered to detect a difference. The trial was at a low risk of bias across most areas. There was an unclear risk of bias related to the use of mean imputation because the investigators did not analyse the impact of imputation on the results. AUTHORS' CONCLUSIONS: There was insufficient evidence to draw reliable and generalisable conclusions regarding potential effectiveness or harm of any pharmacological or non-pharmacological treatments for fatigue in people with PBT. More research is needed on how best to treat people with brain tumours with high fatigue.

High levels of interspecific gene flow in an endemic cichlid fish adaptive radiation from an extreme lake environment.

Studying recent adaptive radiations in isolated insular systems avoids complicating causal events and thus may offer clearer insight into mechanisms generating biological diversity. Here, we investigate evolutionary relationships and genomic differentiation within the recent radiation of Alcolapia cichlid fish that exhibit extensive phenotypic diversification, and which are confined to the extreme soda lakes Magadi and Natron in East Africa. We generated an extensive RAD data set of 96 individuals from multiple sampling sites and found evidence for genetic admixture between species within Lake Natron, with the highest levels of admixture between sympatric populations of the most recently diverged species. Despite considerable environmental separation, populations within Lake Natron do not exhibit isolation by distance, indicating panmixia within the lake, although individuals within lineages clustered by population in phylogenomic analysis. Our results indicate exceptionally low genetic differentiation across the radiation despite considerable phenotypic trophic variation, supporting previous findings from smaller data sets; however, with the increased power of densely sampled SNPs, we identify genomic peaks of differentiation (FST outliers) between Alcolapia species. While evidence of ongoing gene flow and interspecies hybridization in certain populations suggests that Alcolapia species are incompletely reproductively isolated, the identification of outlier SNPs under diversifying selection indicates the radiation is undergoing adaptive divergence.

Niche divergence promotes rapid diversification of East African sky island white-eyes (Aves: Zosteropidae).

The Eastern Afromontane biodiversity hotspot composed of highly fragmented forested highlands (sky islands) harbours exceptional diversity and endemicity, particularly within birds. To explain their elevated diversity within this region, models founded on niche conservatism have been offered, although detailed phylogeographic studies are limited to a few avian lineages. Here, we focus on the recent songbird genus Zosterops, represented by montane and lowland members, to test the roles of niche conservatism versus niche divergence in the diversification and colonization of East Africa's sky islands. The species-rich white-eyes are a typically homogeneous family with an exceptional colonizing ability, but in contrast to their diversity on oceanic islands, continental diversity is considered depauperate and has been largely neglected. Molecular phylogenetic analysis of ~140 taxa reveals extensive polyphyly among different montane populations of Z. poliogastrus. These larger endemic birds are shown to be more closely related to taxa with divergent habitat types, altitudinal distributions and dispersal abilities than they are to populations of restricted endemics that occur in neighbouring montane forest fragments. This repeated transition between lowland and highland habitats over time demonstrate that diversification of the focal group is explained by niche divergence. Our results also highlight an underestimation of diversity compared to morphological studies that has implications for their taxonomy and conservation. Molecular dating suggests that the spatially extensive African radiation arose exceptionally rapidly (1-2.5 Ma) during the fluctuating Plio-Pleistocene climate, which may have provided the primary driver for lineage diversification.

Nocturnal claroteine catfishes reveal dual colonisation but a single radiation in Lake Tanganyika.

Lake Tanganyika (LT) is a biodiversity hotspot supporting many endemic radiations that provide comparative systems in which to investigate if there are common factors leading to the build-up of its considerable diversity. Despite LT containing the highest diversity of lacustrine catfishes on Earth, the evolutionary relationships of nocturnal catfishes within the sub-family Claroteinae have not been investigated and it is unknown if its constituent genera have diversified via single or independent colonisation events. We report the first molecular phylogeny of the LT claroteine catfishes based on a multigene dataset (three nuclear markers, two mitochondrial totalling 4227 bp), including 85 samples from LT and outside of the lake basin. These data support LT claroteine monophyly, with the exclusion of the LT endemic Chrysichthys brachynema that independently colonised the lake but has not radiated. Multiple sampling localities from LT and the use of Bayesian species delimitation methods reveal additional locally restricted diversity within the LT Claroteinae clade. Fossil calibrated molecular divergence dates suggest that diversification occurred within full lake conditions as demonstrated in other LT lineages.

Evolutionary origins and genetic variation of the Seychelles treefrog, Tachycnemis seychellensis (Duméril and Bibron, 1841) (Amphibia: Anura: Hyperoliidae).

The hyperoliid frog Tachycnemis seychellensis, the only species of its genus, is endemic to the four largest granitic islands of the Seychelles archipelago and is reliant on freshwater bodies for reproduction. Its presence in the Seychelles is thought to be the product of a transoceanic dispersal, diverging from the genus Heterixalus, its closest living relative (currently endemic to Madagascar), between approximately 10-35Ma. A previous study documented substantial intraspecific morphological variation among island populations and also among populations within the largest island (Mahé). To assess intraspecific genetic variation and to infer the closest living relative(s) of T. seychellensis, DNA sequence data were generated for three mitochondrial and four nuclear markers. These data support a sister-group relationship between T. seychellensis and Heterixalus, with the divergence between the two occurring between approximately 11-19Ma based on cytb p-distances. Low levels of genetic variation were found among major mitochondrial haplotype clades of T. seychellensis (maximum 0.7% p-distance concatenated mtDNA), and samples from each of the islands (except La Digue) comprised multiple mitochondrial haplotype clades. Two nuclear genes (rag1 and tyr) showed no variation, and the other two (rho and pomc) lacked any notable geographic structuring, counter to patterns observed within presumably more vagile Seychelles taxa such as lizards. The low levels of genetic variation and phylogeographic structure support an interpretation that there is a single but morphologically highly variable species of Seychelles treefrog. The contrasting genetic and morphological intraspecific variation may be attributable to relatively recent admixture during low sea-level stands, ecophenotypic plasticity, local adaptation to different environmental conditions, and/or current and previously small population sizes. Low genetic phylogeographic structure but substantial morphological variation is unusual within anurans.

Continental diversification of an African catfish radiation (Mochokidae: Synodontis).

Despite African rivers containing high species diversity, continental-scale studies investigating the mechanisms generating biological diversity of African riverine faunas are limited compared with lacustrine systems. To investigate the build-up of diversity in a tropical aquatic continental radiation, we test different models of lineage diversification and reconstruct the biogeographic history in a species-rich siluriform genus, Synodontis (~130 species), with a broad distribution across all major tropical African drainage basins. The resulting robust species-level phylogeny (~60% complete, based on a multigene data set) exhibits a near constant rate of lineage accumulation throughout the mid-Cenozoic to recent, irrespective of missing species and despite the changing environmental conditions that were prevalent during this time period. This pattern contrasts with the findings for species-level diversification of large clades that commonly show an early burst of cladogenesis followed by declining rates through time. The identification of distinct biogeographic clades demonstrates a correlation between river hydrology and cladogenesis, although there is evidence of recent repeat dispersal into the southern range of the focal group. We conclude that diverse freshwater fish radiations with tropical continental distributions represent important organisms to test hypotheses of diversification and investigate the effects of palaeo-landscapes and climates on present day biodiversity.

Interventions for preventing and ameliorating cognitive deficits in adults treated with cranial irradiation.

BACKGROUND: Cognitive deficits are common in people who have received cranial irradiation and have a serious impact on daily functioning and quality of life. The benefit of pharmacological and non-pharmacological treatment of cognitive deficits in this population is unclear. OBJECTIVES: To assess the effectiveness of interventions for preventing or ameliorating cognitive deficits in adult patients treated with cranial irradiation. SEARCH METHODS: In August 2014. we searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and PsycINFO and checked the reference lists of included studies. We also searched for ongoing trials via ClinicalTrials.gov, the Physicians Data Query and the Meta Register of Controlled Trials. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that evaluated pharmacological or non-pharmacological interventions in cranial irradiated adults, with objective cognitive functioning as a primary or secondary outcome measure. DATA COLLECTION AND ANALYSIS: Two review authors (JD, KZ) independently extracted data from selected studies and carried out a 'Risk of bias' assessment. Cognitive function, fatigue and mood outcomes were reported. No data were pooled. MAIN RESULTS: Sixteen studies were identified for possible inclusion in the review, six of which were included. Three studies investigated prevention and three studies investigated amelioration. Due to differences between studies in the interventions being evaluated, a meta-analysis was not possible. Two studies investigated a pharmacological intervention for the prevention of cognitive deficits; memantine compared with placebo, and d-threo-methylphenidate HCL compared with placebo. In the first study the primary cognitive outcome of memory at six months did not reach significance, but there was significant improvement in overall cognitive function compared to placebo, with similar adverse events across groups. The second study found no statistically significant difference between arms, with few adverse events. The third study investigated a rehabilitation program for the prevention of cognitive deficits but did not carry out a statistical comparison of cognitive performance between groups.Three studies investigated the use of a pharmacological intervention for the treatment of cognitive deficits; methylphenidate compared with modafinil, two different doses of modafinil, and donepezil compared with placebo. The first study found improvements in cognitive function in both the methylphenidate and modafinil arms; few adverse events were reported. The second study combined treatment arms and found improvements across all cognitive tests, however, a number of adverse events were reported. Both studies were limited by a small sample size. The third study did not find an improvement in the primary cognitive outcome of overall performance, but did find improvement in an individual test of memory, compared to placebo; adverse events were not reported. No non-pharmacological studies for the amelioration of cognitive deficits were eligible. There were a number of limitations across studies but few without high risks of bias. AUTHORS' CONCLUSIONS: There is supportive evidence that memantine may help prevent cognitive deficits for adults with brain metastases receiving cranial irradiation. There is supportive evidence that donepezil may have a role in treating cognitive deficits in adults with primary or metastatic brain tumours who have been treated with cranial irradiation. Patient withdrawal affected the statistical power of both studies. Further research that tries to minimise the withdrawal of consent, and subsequently reduce the requirement for imputation procedures, may offer a higher quality of evidence.There is no strong evidence to support any non-pharmacological interventions (medical or cognitive/behavioural) in the prevention or amelioration of cognitive deficits. Non-randomised studies appear promising but are as yet to be conclusive via translation into high quality evidence. Further research is required.

Predictors of Early Reading Skill in 5-Year-Old Children With Hearing Loss Who Use Spoken Language.

This research investigated the concurrent association between early reading skills and phonological awareness (PA), print knowledge, language, cognitive, and demographic variables in 101 5-year-old children with prelingual hearing losses ranging from mild to profound who communicated primarily using spoken language. All participants were fitted with hearing aids (n = 71) or cochlear implants (n = 30). They completed standardized assessments of PA, receptive vocabulary, letter knowledge, word and non-word reading, passage comprehension, math reasoning, and nonverbal cognitive ability. Multiple regressions revealed that PA (assessed using judgments of similarity based on words' initial or final sounds) made a significant, independent contribution to children's early reading ability (for both letters and words/non-words) after controlling for variation in receptive vocabulary, nonverbal cognitive ability, and a range of demographic variables (including gender, degree of hearing loss, communication mode, type of sensory device, age at fitting of sensory devices, and level of maternal education). Importantly, the relationship between PA and reading was specific to reading and did not generalize to another academic ability, math reasoning. Additional multiple regressions showed that letter knowledge (names or sounds) was superior in children whose mothers had undertaken post-secondary education, and that better receptive vocabulary was associated with less severe hearing loss, use of a cochlear implant, and earlier age at implant switch-on. Earlier fitting of hearing aids or cochlear implants was not, however, significantly associated with better PA or reading outcomes in this cohort of children, most of whom were fitted with sensory devices before 3 years of age.

Outcomes of 3-year-old children with hearing loss and different types of additional disabilities.

This research investigated the speech, language, and functional auditory outcomes of 119 3-year-old children with hearing loss and additional disabilities. Outcomes were evaluated using direct assessment and caregiver report. Multiple regressions revealed that type of additional disability and level of maternal education were significant predictors of language outcomes. Poorer outcomes were achieved in a combined group of children with autism, cerebral palsy, and/or developmental delay (DD) (Group A), compared with children with vision or speech output impairments, syndromes not entailing DD, or medical disorders (Group B). Better outcomes were associated with higher levels of maternal education. The association between better language outcomes and earlier cochlear implant switch-on approached significance. Further regression analyses were conducted separately for children with different types of additional disabilities. Level of maternal education was the only significant predictor of outcomes for Group A children, whereas degree of hearing loss was the strongest predictor for children in Group B. The findings highlight the variable impact that different types of additional disabilities can have on language development in children with hearing loss.