Seal evolution: Sexual dimorphism in pinnipeds arose around 27 million years ago as climate changed

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In the world of science, one of the most exciting things a researcher can do is pin down an answer to a widely asked question. This experience came early for Carleton University graduate Thomas Cullen, who made a discovery about pinnipeds — the suborder that makes up seals, sea lions and walruses — while doing research for his Master’s degree under the supervision of Canadian Museum of Nature palaeontologist Dr. Natalia Rybczynski.His discovery, published today in the journal Evolution, relates to sexual dimorphism (a large variance in size between males and females), in a variety of pinniped species. Males in many species of pinnipeds are often much larger than their female counterparts, in some cases more than twice as large, and this has implications for how they mate and behave.Dimorphic pinnipeds such as the Steller’s Sea Lion and Northern Fur Seal typically mate in a harem, with one male pinniped presiding over a larger community of female mates. This behavior is not typically seen in non-dimorphic pinnipeds such as the Ringed Seal, and so sexual dimorphism is intimately linked with mating style.Researchers have long puzzled over both why sexual dimorphism exists in many pinniped species and when this trait evolved. When Cullen examined fossils of an extinct pinniped with Rybczynski, he discovered an incontrovertible answer to the question of when. He was able to examine it there before analyzing the data at Carleton in a lab headed by his other thesis supervisor, Prof. Claudia Schrder-Adams.Skull of Enaliarctos emlongi, an early pinniped ancestor. Cullen examined and analyzed the characteristics of this fossil for his study on the evolution of sexual dimorphism in pinnipeds.”We were examining a fossil of a pinniped that was previously thought to be a juvenile, but we looked at it again and found that, based on its skull structure, it was likely an adult,” says Cullen. This discovery, coupled with analyses comparing this fossil to others of the same species as well as modern dimorphic species, proved that the fossil belonged to a sexually dimorphic species.The fossil in question, the skull of an early pinniped ancestor called Enaliarctos emlongi, was discovered in the late 1980s off the coast of Oregon. …


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Growing impact of lethal "legal highs:" U.K. Deaths report

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The deadly risk of so-called ‘legal highs’ and other designer drugs, such as the notorious ‘meow meow’, has been confirmed by a huge leap in their links to drug-related deaths in the UK. One expert described experimentation with such drugs as ‘dancing in a minefield.”Meow meow’, officially known as mephedrone and now illegal, is just one of a group of drugs called Novel Psychoactive Substances (NPS), which also includes the amphetamine-like substances Benzo Fury and PMA, amongst others.According to data published in the National Programme on Substance Abuse Deaths (NPSAD) report, compiled by experts at St George’s, University of London, NPS are now linked to more drug-related deaths than ever before.The prevalence of these drugs in the post mortem toxicology tests submitted to the report has increased 800% in three years, from 12 in 2009 to 97 in 2012.The number of cases where NPS were identified as the cause of death rose by almost 600% during the same period — from 10 deaths in 2009 to 68 in 2012.In many cases traces of multiple NPS were found, suggesting that drug users are experimenting with combinations of these drugs, as well as alcohol in some cases.These drugs have undergone little or no human testing so their health effects are virtually unknown.Professor Fabrizio Schifano, a spokesman for NPSAD, said: “We have observed an increase in the number and range of these drugs in the post mortem toxicology results and in the cause of death of cases notified to us.”These include amphetamine-type substances, dietary supplements, ketamine derivatives, among a host of others.”The worrying trend is that these type of drugs are showing up more than ever before. Clearly this is a major public health concern and we must continue to monitor this worrying development.”Those experimenting with such substances are effectively dancing in a minefield.”The report also indicates an increase in the proportion of deaths involving stimulants such as cocaine and ecstasy-type drugs, following a decline in 2009 and stabilisation in 2010.In total, the number of drug-related deaths reported to the NPSAD during 2012 was 1,613.Opiates/opioids such as heroin and morphine, alone or in combination with other drugs continued to account for the highest proportion (36%) of reported drug-related deaths in 2012, a 4% increase compared to 2011 — a reversal of the decline in such deaths observed in recent years.Regional Highlights:Hammersmith one of worst areas in UK for drug-related deaths, says reportNew figures reveal that Hammersmith and Fulham recorded one of the highest drug-related death rates across the country in 2012 with 11.34 deaths per 100,000 population.Only Liverpool (12.57) and Blackburn with Darwen (11.45) were higher.The type of drugs related to deaths in London also drew a strong contrast to some other parts of England. As in 2011, London had the highest proportion of cocaine-related deaths in the country (15.2%), contrasting greatly with other regions, such as the Midlands and East of England where cocaine was implicated in just 3.4% of drug-related deaths.However, it is important to note that when taking into account absolute figures, Liverpool alone had more deaths involving cocaine, which was 20, than the whole of the following regions: Midlands and East of England; London; and the South of England.Liverpool overtakes Manchester with highest rates of drug-related deaths in the North West, reveals new reportThe number of drugs-related deaths in Liverpool has risen above those in Manchester for the first time since 2006 according to a new study.For the first time in over five years there were more drug-related deaths in Liverpool, which saw 49 such cases, compared to Manchester with 36.The report, compiled by researchers at St George’s, University of London, also found that Liverpool alone had more deaths linked to cocaine than the whole of the Midlands and East of England region, London and the South of England.Drugs deaths in Northern Ireland buck wider UK trend of lethal heroin useDeaths related to drugs in Northern Ireland show a marked difference from the rest of the UK as fatalities are mostly linked to prescription drugs, says a new report.Whereas the vast majority of drug-related deaths in the UK are linked to opiates such as heroin and morphine, in the province most relate to other drugs.The new research from St George’s, University of London, also shows a small decrease in the overall number of drug-related deaths in Northern Ireland. There were 78 such deaths in 2012 as opposed to 82 in 2011.Northern Ireland contrasts the rest of the UK with higher proportions of deaths attributed to drugs such as tramadol, benzodiazepines and anti-depressants. Northern Ireland also displayed a substantially lower proportion of deaths attributed to heroin/morphine and methadone than other regions of the UK, such as the South of England, the midlands and London.


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Meeting the eye-witnesses of ocean change

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Members of the German research network BIOACID (Biological Impacts of Ocean Acidification) are developing a model that links ecosystem changes triggered by ocean acidification and climate change with their economic and societal consequences. Workshops and interviews with stakeholders from the Norwegian fishing industry and tourism sector, the government and environmental organisations help them to identify key aspects for their assessment.During the past ten years, scientists have learned a lot about the effects of ocean acidification on marine ecosystems. It has become obvious that with rising carbon dioxide emissions from human activities, oceans absorb larger amounts of this greenhouse gas and become more acidic. The increase of acidity, rising water temperatures and other stressors may alter marine ecosystems dramatically — with consequences for economy and society.Do stakeholders of the economic sectors which depend on the sea already observe signs of ocean change? Which are their most urgent questions towards science? Within the framework of the German research network BIOACID (Biological Impacts of Ocean Acidification), scientists from the University of Bremen investigated stakeholders’ state of knowledge and identified focal points for further research. Between March and November 2013, they held workshops and interviewed more than 30 Norwegian fishers, representatives from fishing associations, aquaculture, tourism, environmental organisations and governmental agencies. They aim to develop a model that yields insights into the overall impacts of ocean change for ecosystems and the services they provide to human societies.”Taking a systems view can help to analyse socio-economic impacts of ocean acidification and find ways to mitigate them and adapt to them,” Dr. Stefan Gling-Reisemann, researcher at the Sustainability Research Center (artec) at the University of Bremen explains. “This is why we connect stakeholders and scientists and adapt further research to the demands of society.” Norway was chosen because the fishing industry, a branch that is likely to be hit first by effects of climate change, plays a very important economic role there. …


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#Change, #Climate, #Ecology, #Health, #Northern, #Norway, #Norwegian, #Oceanacidification, #People, #Research, #Result, #Science