Biotic and Human Vulnerability to Projected Changes in Ocean Biogeochemistry over the 21st Century

Ongoing greenhouse gas emissions can modify climate processes and induce shifts in ocean temperature, pH, oxygen concentration, and productivity, which in turn could alter biological and social systems. Here, we provide a synoptic global assessment of the simultaneous changes in future ocean biogeochemical variables over marine biota and their broader implications for people. We analyzed modern Earth System Models forced by greenhouse gas concentration pathways until 2100 and showed that the entire world''s ocean surface will be simultaneously impacted by varying intensities of ocean warming, acidification, oxygen depletion, or shortfalls in productivity. In contrast, only a small fraction of the world''s ocean surface, mostly in polar regions, will experience increased oxygenation and productivity, while almost nowhere will there be ocean cooling or pH elevation. We compiled the global distribution of 32 marine habitats and biodiversity hotspots and found that they would all experience simultaneous exposure to changes in multiple biogeochemical variables. This superposition highlights the high risk for synergistic ecosystem responses, the suite of physiological adaptations needed to cope with future climate change, and the potential for reorganization of global biodiversity patterns. If co-occurring biogeochemical changes influence the delivery of ocean goods and services, then they could also have a considerable effect on human welfare. Approximately 470 to 870 million of the poorest people in the world rely heavily on the ocean for food, jobs, and revenues and live in countries that will be most affected by simultaneous changes in ocean biogeochemistry. These results highlight the high risk of degradation of marine ecosystems and associated human hardship expected in a future following current trends in anthropogenic greenhouse gas emissions.     

Replicated high-density genetic maps of two great tit populations reveal fine-scale genomic departures from sex-equal recombination rates

Linking variation in quantitative traits to variation in the genome is an important, butchallenging task in the study of life-history evolution. Linkage maps provide a valuabletool for the unravelling of such trait−gene associations. Moreover, they giveinsight into recombination landscapes and between-species karyotype evolution. Here weused genotype data, generated from a 10k single-nucleotide polymorphism (SNP) chip, ofover 2000 individuals to produce high-density linkage maps of the great tit (Parusmajor), a passerine bird that serves as a model species for ecological andevolutionary questions. We created independent maps from two distinct populations: acaptive F2-cross from The Netherlands (NL) and a wild population from the United Kingdom(UK). The two maps contained 6554 SNPs in 32 linkage groups, spanning 2010 cM and1917 cM for the NL and UK populations, respectively, and were similar in size andmarker order. Subtle levels of heterochiasmy within and between chromosomes wereremarkably consistent between the populations, suggesting that the local departures fromsex-equal recombination rates have evolved. This key and surprising result would have beenimpossible to detect if only one population was mapped. A comparison with zebra finchTaeniopygia guttata, chicken Gallus gallus and the green anole lizardAnolis carolinensis genomes provided further insight into the evolution ofavian karyotypes.     

A comparative study on efficiency of adult fibroblasts and amniotic fluid-derived stem cells as donor cells for production of hand-made cloned buffalo (Bubalus bubalis) embryos

The efficiency of two cell types, namely adult fibroblasts, and amniotic fluid stem (AFS) cells as nuclear donor cells for somatic cell nuclear transfer by hand-made cloning in buffalo (Bubalus bubalis) was compared. The in vitro expanded buffalo adult fibroblast cells showed a typical “S” shape growth curve with a doubling time of 40.8 h and stained positive for vimentin. The in vitro cultured undifferentiated AFS cells showed a doubling time of 33.2 h and stained positive for alkaline phosphatase, these cells were also found positive for undifferentiated embryonic stem cell markers like OCT-4, NANOG and SOX-2, which accentuate their pluripotent property. Further, when AFS cells were exposed to corresponding induction conditions, these cells differentiated into osteogenic, adipogenic and chondrogenic lineages which was confirmed through alizaran, oil red O and alcian blue staining, respectively. Cultured adult fibroblasts and AFS cells of passages 10–15 and 8–12, respectively, were used as nuclear donors. A total of 94 embryos were reconstructed using adult fibroblast as donor cells with cleavage and blastocyst production rate of 62.8 ± 1.8 and 19.1 ± 1.5, respectively. An overall cleavage and blastocyst formation rate of 71.1 ± 1.2 and 29.9 ± 2.2 was obtained when 97 embryos were reconstructed using AFS cells as donor cells. There were no significant differences (P > 0.05) in reconstructed efficiency between the cloned embryos derived from two donor cells, whereas the results showed that there were significant differences (P < 0.05) in cleavage and blastocyst rates between the cloned embryos derived from two donor cell groups. Average total cell numbers for blastocyst generated using AFS cells (172.4 ± 5.8) was significantly (P < 0.05) higher than from adult fibroblasts (148.2 ± 6.1). This study suggests that the in vitro developmental potential of the cloned embryos derived from AFS cells were higher than that of the cloned embryos derived from adult fibroblasts in buffalo hand-made cloning.     

Socioeconomic inequalities in incidence of lung and upper aero-digestive tract cancer by age, tumour subtype and sex: a population-based study in Scotland (2000-2007)

BackgroundLung and upper aero-digestive tract (UADT) cancer risk is associated with socioeconomic inequality (SEI) but the degree of socioeconomic burden by age, tumour subtype, and sex is not known.MethodsWe reviewed 216,305 cases excluding non melanoma skin cancer (All Cancer) comprising 37,274 lung; 8216 head and neck; and 6534 oesophageal cancers from 2000 to 2007 classified into anatomical or morphology subtypes. Deprivation was measured using the Scottish Index of Multiple Deprivation and SEI was measured using the Slope Index of Inequality and the Relative Index of Inequality (RII). Analyses were partitioned by 5-year age group and sex. RII was adapted to rank tumour type contribution to All Cancer SEI and to examine subtype by age and sex simultaneously. Rank was defined as proportion of All Cancer SEI.ResultsAll Cancer SEI was greater for males (RII = 0.366; female RII = 0.279); the combination of lung and UADT SEI contributed 91% and 81% respectively to All Cancer SEI. For both sexes lung and UADT subtypes showed significant SEI (P < 0.001) except oesophageal adenocarcinoma in males (P = 0.193); for females, SEI was borderline significant (P = 0.048). Although RII rank differed by sex, all lung and larynx subtypes contributed most to All Cancer SEI with RII rank for oral cavity, oesophagus-squamous cell, and oropharynx following. For males 40–44 years, SEI increased abruptly peaking at 55–59 years. For females, SEI gradually peaked 10 years later. In both sexes, the SEI peak preceded peak incidence.ConclusionSEI in lung and UADT cancers vary greatly by age, tumour subtype and sex; these variations are likely to largely reflect differences between the sexes in risk behaviours which vary by birth cohort and are socioeconomically patterned.     

Meta‐analysis reveals the importance of matrix composition for animals in fragmented habitat

Aim Connectivity is a key determinant of the distribution and abundance of organisms and is greatly influenced by anthropogenic landscape modification, yet we lack a synthetic perspective on the magnitude and extent of matrix effects on connectivity. We synthesize results from published studies to understand the importance of matrix effects on fragmented animal populations. Location Global. Methods We conduct a meta‐analysis of 283 fragmented populations representing 184 terrestrial animal taxa to determine the strength of matrix composition effects on the occurrence and abundance of animals in fragmented habitat. Results Studies that use data on matrix composition report greater effects on abundance and occupancy of fragmented populations than studies that define connectivity without regard to the surrounding matrix (i.e. ‘binary’ studies that describe only characteristics of patch habitat). Main conclusions Our findings underscore that conservation strategies must consider the importance of matrix habitat, have important implications for metapopulation and metacommunity paradigms, and provide direct large‐scale, multi‐taxa evidence that matrix habitat is an important driver of ecological dynamics in heterogeneous landscapes.     

Effects on the ecological integrity of a soft-bottom habitat from a trawling disturbance

The effects of trawling disturbance on a soft-sediment system were investigated with a manipulative field experiment in an area that had been closed to shrimp trawling activities for 20 years. The area was also chosen for its weak natural physical agents i.e. no scouring of sediments by storm events or tidal flow, allowing a quantitative assessment of the effects of trawling on the benthic fauna and geochemical properties of the soft substrate.The study examined the ambient spatial and temporal patterns of sedimentological variables and benthic species abundances over a time interval of 16 months for both the reference and the trawl stations before dragging the trawling gear over the predetermined trawl sites. Shifts in the patterns of the benthic infauna and geochemical variables were identified by the post-trawl samples that were collected at both the reference and trawl stations over the next 6 months. Post-trawl changes in the bottom topography did not translate into changes in the vertical profile of the sedimentological variables. Chlorophyll a content of the trawled surface sediments was significantly elevated immediately after the trawling event in comparison to the reference concentrations.Immediately after the trawling disturbance, numbers of species, species abundance and diversity decreased in the trawled area in comparison to the reference area. Sensitive species were found to be the bivalves; Ennucula annulata, Hampson, Thyasira flexuosa (Montagu), and Yoldia sapotilla (Gould), and polychaetes; Chaetozonecf.setosa Malmgren, Anobothrus gracilis(Malmgren), Euchone incolor Hartman, and Terebellides atlantis Williams. In contrast, the carnivorous nemertea, Cerebratulus lacteus Verrill, was the resistant species to field manipulations on account of its predatory behavior; highly effective in seeking out freshly dead (dying) organisms and its active migration. Multivariate analysis confirmed the changes in the trawled community structure immediately following the trawling event and differences in the recovery patterns 6 months thereafter. Although the trawling disturbance was one of low frequency and intensity compared to commercial operations, the biological variables studied indicated that successional processes in this soft-bottom community were altered, at least for a short period, in response to the trawling disturbance.     

Signaling through a mutant IFN-gamma receptor

Activation of STAT1 and the IFN-gamma response are thought to be mediated exclusively through the Y440 motif of the human IFNGR1 receptor subunit. Contrary to this accepted dogma, here it is shown that IFNGR1 with a mutant (Y440F) motif, when stably expressed in IFNGR1-negative human fibroblasts at levels similar to wild type, can sustain a substantial IFN-gamma response. The mutant receptor supports selective induction of IFN-gamma-inducible genes but is notably defective in the CIITA, class II HLA, suppressor of cytokine signaling and antiviral responses. Remarkably, similar selective defects are observed in human fibrosarcoma cells expressing a mutant JAK1. The phenotypes are novel and appear distinct from those observed in response to the inhibition of known additional pathways. Data from different cell types further emphasizes the importance of cellular background in determining the response.     

Observations of terrestrial locomotion in wild Polypterus senegalus from Lake Albert,Uganda

Polypterids, the most basal actinopterygians, are a group of fish long-considered living fossils and holding a key position for understanding fish and tetrapod evolution. Knowledge of the natural history of Polypterus is limited, their having been studied in little detail since the early 1900s. The locomotory habits of wild Polypterus senegalus from Lake Albert, Uganda, were investigated in 2014. High-speed videography demonstrated the capability of large Polypterus to move overland successfully. Contrary to previous evidence, field observations found that terrestrial locomotion in Polypterus is not inherently restricted by body size. Evidence that Polypterus exhibit this behaviour as part of their natural life history can be found in the existence of environmental challenges and the presence of adaptations for amphibious life.