Insights into birds’ migration routes

Date:July 21, 2014Source:WileySummary:By tracking hybrids between songbird species, investigators have found that migration routes are under genetic control and could be preventing interbreeding. The research was conducted using geolocators that, like GPS, record the position of a bird and allow its long distance movement to be tracked.By tracking hybrids between songbird species, investigators have found that migration routes are under genetic control and could be preventing interbreeding. The research, which is published in Ecology Letters, was conducted using geolocators that, like GPS, record the position of a bird and allow its long distance movement to be tracked.Compared with their parents, hybrids exhibited increased variability in their migratory routes: some used intermediate routes across less suitable areas, while others used the same routes as one parental group on fall migration and the other on spring migration.”This is the first time we’ve been able to track songbirds over the entire annual cycle, and the data we collected support a longstanding hypothesis in ecological speciation, that differences in migratory behavior could be acting as postmating reproductive isolating barriers,” said lead author Kira Delmore.Story Source:The above story is based on materials provided by Wiley. Note: Materials may be edited for content and length.Journal Reference:Kira E. Delmore, Darren E. Irwin. Hybrid songbirds employ intermediate routes in a migratory divide. Ecology Letters, 2014; DOI: 10.1111/ele.12326 Cite This Page:MLA APA Chicago Wiley. “Insights into birds’ migration routes.” ScienceDaily. ScienceDaily, 21 July 2014. …

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Converting land to agriculture reduces carbon uptake, study shows

University of Montana researchers examined the impact that converting natural land to cropland has on global vegetation growth, as measured by satellite-derived net primary production, or NPP. They found that measures of terrestrial vegetation growth actually decrease with agricultural conversion, which has important implications for terrestrial carbon storage.Postdoctoral researcher Bill Smith and UM faculty members Steve Running and Cory Cleveland, along with a former UM postdoctoral researcher and current USGS scientist Sasha Reed, used estimates of agricultural NPP and satellite-derived estimates of natural NPP to evaluate the impact of expanding agricultural land to meet needs for food and fiber. Terrestrial NPP represents the total annual growth of vegetation on the land, which is a critical factor that helps determine how much carbon can be absorbed and stored from the atmosphere.Their results show that agricultural conversion has reduced that productivity by approximately 7 percent. A small percentage of intensively managed, irrigated or fertilized agricultural land shows an increase in productivity. However, productivity is reduced in 88 percent of agricultural lands globally, with the largest reductions in former tropical forests and savannas.”Current forecasts suggest that global food demand will likely double by 2050,” Smith said. “We hope that this research will help to identify strategies that, from a carbon balance perspective, should be avoided due to the potential for severe degradation of global vegetation growth and carbon storage.”The research was published in Geophysical Research Letters and highlighted in the February 2014 issue of Nature Geoscience.Story Source:The above story is based on materials provided by The University of Montana. Note: Materials may be edited for content and length.

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‘Insect soup’ holds DNA key for monitoring biodiversity

Aug. 5, 2013 — Scientists at the University of East Anglia have shown that sequencing the DNA of crushed up creepy crawlies can accelerate the monitoring and cataloguing of biodiversity around the world.Research published today in the journal Ecology Letters shows that a process known as ‘metabarcoding’ is much faster than and just as reliable as standard biodiversity datasets assembled with traditional labour-intensive methods.The breakthrough means that changing environments and endangered species can be monitored more easily than ever before. It could help researchers find endangered tree kangaroos in Papua New Guinea, discover which moths will be wiped out by climate change, and restore nature to heathlands in the UK, rubber plantations in China, and oil-palm plantations in Sumatra.Lead researcher Dr Douglas Yu, from UEA’s school of Biological Sciences, said: “Every living organism contains DNA, and even small fragments of that DNA can be used to identify species.”We collected lots of insects and other creepy-crawlies, ground them up into an ‘insect soup’, and read the DNA using sequencers that are now cheap enough to use weekly or even daily.”We compared our results with high-quality datasets collected in Malaysia, China and the UK which combined more than 55,000 arthropod and bird specimens and took experts 2,505 hours to identify. These kinds of datasets are the gold standard for biodiversity monitoring but are so expensive to compile that that we cannot use them for regular monitoring. Thus, conservation biologists and environmental managers are forced to work with little information.”We found that our ‘soup’ samples give us the same biodiversity information as the gold-standard datasets. They are also more comprehensive, many times quicker to produce, less reliant on taxonomic expertise, and they have the added advantage of being verifiable by third parties.”The findings are important because they show that metabarcoding can be used to reliably inform policy and environmental management decisions.Dr Yu added: “If the environment changes for the better or for the worse, what lives in that environment changes as well. Insect soup becomes a sensitive thermometer for the state of nature.”For instance, we showed that if the UK Forestry Commission ploughs up some of the grass-covered trackways that run between our endangered heathland habitats, populations of rare spiders, beetles, and other creepy-crawlies can reconnect along those trackways, helping to stave off extinction.”We are now working with the WWF and Copenhagen University to apply the method to bloodsucking leeches to look for endangered mammals in Vietnamese and Laotian rainforests. By creating a ‘leech soup’ we can get a list of mammals and know more about whether park conservation is working.”Each soup combines hundreds to thousands of insects caught using insect traps. The numbers captured amount to a tiny fraction of their overall populations and pose no threat to endangered species.The research was funded by the Natural Environment Research Council UK, the Chinese Academy of Sciences, the National Science Foundation of China, and the Yunnan provincial government.’Reliable, verifiable, and efficient monitoring of biodiversity via metabarcoding’ is published in the journal Ecology Letters on August 5, 2013.

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Artificial organelles transform free radicals into water and oxygen

July 16, 2013 — Researchers at the University of Basel have successfully developed artificial organelles that are able to support the reduction of toxic oxygen compounds. This opens up new ways in the development of novel drugs that can influence pathological states directly inside the cell.The results have been published in the journal Nano Letters.Free oxygen radicals are produced either as metabolic byproduct, or through environmental influences such as UV-rays and smog. Is the concentration of free radicals inside the organism elevated to the point where the antioxidant defense mechanism is overwhelmed, the result can be oxidative stress, which is associated with numerous diseases such as cancer of arthritis.The aggressive molecules are normally controlled by endogenous antioxidants. Within this process, organelles located inside the cell, so-called peroxisomes, play an important part, since they assist in regulating the concentration of free oxygen radicals.Nanocapsules Transform Radicals into Water and OxygenProf. Cornelia Palivan and her research group at the University of Basel have successfully produced artificial peroxisomes that mimic the natural organelle. The researchers developed a cell organelle based on polymeric nanocapsules, in which two types of enzymes are encapsulated. These enzymes are able to transform free oxygen radicals into water and oxygen.In order to verify the functionality inside the cell, channel proteins were added to the artificial peroxisome’s membrane, to serve as gates for substrates and products. The results show that the artificial peroxisomes are incorporated into the cell, where they then very efficiently support the natural peroxisomes in the detoxification process.Novel DrugsThis type of effective principle targets the cell dysfunction directly on the cellular level, thus representing a further step towards the development of novel drugs that will make patient-oriented and personalized treatments possible in the future.

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Air pollution responsible for more than 2 million deaths worldwide each year, experts estimate

July 12, 2013 — More than two million deaths occur worldwide each year as a direct result of human-caused outdoor air pollution, a new study has found.In addition, while it has been suggested that a changing climate can exacerbate the effects of air pollution and increase death rates, the study shows that this has a minimal effect and only accounts for a small proportion of current deaths related to air pollution.The study, which has been published today, 12 July, in IOP Publishing’s journal Environmental Research Letters, estimates that around 470,000 people die each year because of human-caused increases in ozone.It also estimates that around 2.1 million deaths are caused each year by human-caused increases in fine particulate matter (PM2.5) ? tiny particles suspended in the air that can penetrate deep into the lungs, causing cancer and other respiratory disease.Co-author of the study, Jason West, from the University of North Carolina, said: “Our estimates make outdoor air pollution among the most important environmental risk factors for health. Many of these deaths are estimated to occur in East Asia and South Asia, where population is high and air pollution is severe.”According to the study, the number of these deaths that can be attributed to changes in the climate since the industrial era is, however, relatively small. It estimates that a changing climate results in 1500 deaths due to ozone and 2200 deaths related to PM2.5 each year.Climate change affects air quality in many ways, possibly leading to local increases or decreases in air pollution. For instance, temperature and humidity can change the reaction rates which determine the formation or lifetime of a pollutant, and rainfall can determine the time that pollutants can accumulate.Higher temperatures can also increase the emissions of organic compounds from trees, which can then react in the atmosphere to form ozone and particulate matter.”Very few studies have attempted to estimate the effects of past climate change on air quality and health. We found that the effects of past climate change are likely to be a very small component of the overall effect of air pollution,” continued West.In their study, the researchers used an ensemble of climate models to simulate the concentrations of ozone and PM2.5 in the years 2000 and 1850. A total of 14 models simulated levels of ozone and six models simulated levels of PM2.5.Previous epidemiological studies were then used to assess how the specific concentrations of air pollution from the climate models related to current global mortality rates.The researchers’ results were comparable to previous studies that have analysed air pollution and mortality; however, there was some variation depending on which climate model was used.”We have also found that there is significant uncertainty based on the spread among different atmospheric models. This would caution against using a single model in the future, as some studies have done,” continued West.

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New evidence on easing inflammation of brain cells for Alzheimer’s disease

Oct. 3, 2012 — New research proves the validity of one of the most promising approaches for combating Alzheimer’s disease (AD) with medicines that treat not just some of the symptoms, but actually stop or prevent the disease itself, scientists are reporting.Share This:The study, in the journal ACS Medicinal Chemistry Letters, also identifies a potential new oral drug that the scientists say could lead the way.Wenhui Hu and colleagues point out that existing drugs for AD provide only “minimal” relief of memory loss and other symptoms, creating an urgent need for new medicines that actually combat the underlying destruction of brain cells. Research suggests that inflammation of nerve cells in the brain is a key part of that process. One medicine, Minozac, is in clinical trials. But Hu says Minozac still has more space to improve its efficacy. So the scientists sifted through compounds with a molecular architecture similar to Minozac in an effort to find more active substances.The report describes success in doing so. They discovered one compound that appeared especially effective in relieving nerve inflammation and in improving learning and memory in lab mice widely used in AD research. “In general, this study not only proves that countering neuroinflammation is indeed a potential therapeutic strategy for Alzheimer’s disease, but also provides a good lead compound with efficacy comparable to donepezil [an existing AD medicine] for further oral anti-AD drug discovery and development,” the report states.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is reprinted from materials provided by American Chemical Society. Note: Materials may be edited for content and length. For further information, please contact the source cited above. …

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Cooling ocean temperature could buy more time for coral reefs

May 14, 2013 — Limiting the amount of warming experienced by the world’s oceans in the future could buy some time for tropical coral reefs, say researchers from the University of Bristol.

The study, published by the journal Geophysical Research Letters, used computer models to investigate how shallow-water tropical coral reef habitats may respond to climate change over the coming decades.

Elena Couce and colleagues found that restricting greenhouse warming to three watts per square metre (equivalent to just 50-100 parts per million carbon dioxide, or approximately half again the increase since the Industrial Revolution) is needed in order to avoid large-scale reductions in reef habitat occurring in the future.

Shallow-water tropical coral reefs are amongst the most productive and diverse ecosystems on the planet. They are currently in decline due to increasing frequency of bleaching events, linked to rising temperatures and fossil fuel emissions.

Elena Couce said: “If sea surface temperatures continue to rise, our models predict a large habitat collapse in the tropical western Pacific which would affect some of the most biodiverse coral reefs in the world. To protect shallow-water tropical coral reefs, the warming experienced by the world’s oceans needs to be limited.”

The researchers modelled whether artificial means of limiting global temperatures — known as solar radiation ‘geoengineering’ — could help. Their results suggest that if geoengineering could be successfully deployed then the decline of suitable habitats for tropical coral reefs could be slowed. They found, however, that over-engineering the climate could actually be detrimental as tropical corals do not favour overly-cool conditions. Solar radiation geoengineering also leaves unchecked a carbon dioxide problem known as ‘ocean acidification’.

Elena Couce said: “The use of geoengineering technologies cannot safeguard coral habitat long term because ocean acidification will continue unabated. Decreasing the amount of carbon dioxide in the atmosphere is the only way to address reef decline caused by ocean acidification.”

Dr Erica Hendy, one of the co-authors, added: “This is the first attempt to model the consequences of using solar radiation geoengineering on a marine ecosystem. There are many dangers associated with deliberate human interventions in the climate system and a lot more work is needed to fully appreciate the consequences of intervening in this way.”

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