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In the news this week: the dinosaurs’ demise didn’t cause mammalian success, the government is warned about failing nanoscience and pizza gets a nutrition makeover...

It has long been assumed that it was the extinction of dinosaurs 65 million years ago that enabled mammals to diversify, flourish and occupy their position today as the world’s dominant large animals. However, a family “supertree” constructed using genetic data collected from 99 per cent of the 4,500 species that currently exist, suggests that the demise of dinosaurs had little effect on the evolution of mammals. Instead, it reveals that mammals underwent one important phase of evolution 80-100 million years ago. The rapid phase of evolution that gave rise to modern groups such as primates and rodents, didn’t take place until 10-15 million years after dinosaurs died out. The findings reconcile existing DNA and fossil evidence.

‘It looks like a later bout of global warming may have kick-started today’s diversity – not the death of the dinosaurs,’ said Professor Andy Purvis, one of the study leaders, in the Times.

Co-author Dr Kate Jones explained the work behind the study to the BBC: ‘If we had done this from scratch, we would have had to get molecular and morphological data for 4,000 different species. What we did instead was use already published information from hundreds of researchers around the world. We used a new technique called supertree construction which allows us to get all the information that’s out there, re-code it and re-analyse it as if it’s all part of one dataset.’

Global warming continues to be high on the agenda of UK politics. But despite this, BBC News reported that our carbon emissions increased by 1.25 per cent last year. It seems a major culprit is the switch from gas to coal for electricity generation. This higher carbon fuel is being used because its cost has risen less than gas prices.

Another BBC News story shared the findings of a report commissioned by the environmental group WWF: between 1999 and 2006 UK power sector emissions rose by nearly 30 per cent.

The Forestry Commission has devised a new strategy that could save 400,000 tonnes of carbon each year. The plan is to increase the amount of wood from managed woodlands to be used for energy, reported BBC News. Provided the woods are restocked, and harvesting and processing does not use much fossil fuel, burning wood can be considered essentially carbon neutral.

BBC News also reported that certain British peat bogs, which absorb and store carbon, are drying out due to damage. The National Trust believes this could be contributing significant amounts of carbon dioxide to the atmosphere and are urging the government to conserve peat bogs. Only certain peatlands have been studied in detail so the extent of carbon leakage is unknown, but 1,350 hectares of degraded bog in the Peak District have been found to be releasing 37,000 tonnes of carbon annually – that’s as much as 18,000 cars emit.

Meanwhile, Portugal has opened a solar plant that it says is the world’s most powerful yet. The solar panels cover about 60 hectares and are predicted to produce enough energy to supply 8,000 homes, reported BBC News.

A team of scientists have conducted an analysis of emission scenarios laid out by the Intergovernmental Panel on Climate Change (IPCC) to predict the locations of temperature and precipitation changes. If development continues along the track it is now, by the end of the century 12-39 per cent of the Earth’s land surface will have a new climate. Climatic conditions on up to 48 per cent will have ceased to exist altogether. This could have devastating effects on species that are unable to move to stay within their preferred climate conditions or adapt to cope with the changes, reported the Guardian.

In other news, leading science advisors have accused the UK government of failing to adequately fund research into the potential risks of developing nanotechnology. The government committed to “an immediate programme of research” in 2005 in response to a report published by the Royal Society and Royal Academy of Engineering. But a review of progress conducted by the Council of Science and Technology (CST) reveals that, while efforts to measure and minimise workplace exposure to nanomaterials have progressed, insufficient has been done to understand possible environmental and health effects.

While 90 million pounds was spent on promoting and advancing nanotechnology research in 2004 alone, a mere 600,000 pounds a year average has been spent on researching the impacts of nanomaterials over the past five years, reported BBC News.

‘More targeted research to reduce the uncertainties around the health and environmental effects of nanomaterials must be funded,’ said Professor Ann Dowling, who chaired the working group of the original 2004 report. ‘This is a vital step to ensuring that nanotechnologies are well regulated and inspire the confidence of the public and investors.’ She believes without this, the UK risks losing the competitive edge it currently has in nanoscience.

Batteries powered by sugary drinks could be on the market within five years, according to researchers. The sugar battery prototype is made from biodegradable materials and is the most powerful yet devised. So far, sugared water, still soft drinks, glucose and tree saps have all been used successfully. The sugar is oxidised into electrons and protons by dehydrogenase enzymes in the battery.

The Times quoted Dr Shelley Minteer, who presented the work at the American Chemical Society conference: ‘This study shows that renewable fuels can be directly employed in batteries at room temperature to lead to more energy-efficient battery technology than metal-based approaches. It demonstrates that by bridging biology and chemistry, we can build a better battery that’s cleaner for the environment.’

According to UK asthma experts, a technique known as bronchial thermoplasty could help fight asthma in the future, reported the New Scientist. The procedure uses radio waves to reduce the amount of smooth muscle lining the patients’ airways and doctors believe this results in reduced inflammation. In the recent trial, the treatment helped asthma sufferers control their symptoms for up to a year.

112 people aged 18-65 with asthma took part in the study. All continued to have access to their usual inhaler medication and, in addition, half received three thermoplasty treatments. The latter group experienced half as many mild asthma attacks as the former and also had far more symptom-free days.

An American study was published this week that showed a significant link between regular beef consumption by mothers during pregnancy and low sperm counts in their offspring. While no direct link with a cause could be made, the researchers suggest that growth hormones and steroids used in cattle may be responsible.

Lead author, Professor Shanna Swan, said: ‘Theoretically, the foetus and young children are particularly sensitive to exposure to sex steroids. Therefore, the consumption of residues of steroids in meat by pregnant women and young children is of particular concern.

‘What we’re really doing here is raising an issue,’ she commented in the Daily Telegraph. ‘The average sperm concentration of the men in our study went down as their mothers’ beef intake went up.’

The Times added that the hormones of concern were banned throughout the EU in 1988, and were never widely used in Britain.

In other news, pollen grains could help solve the mystery of where China’s 2,200-year-old terracotta army was made. Soils from different areas contain distinct pollen ‘signatures’, reflecting vegetation differences. Scientists separately analysed components of the clay from a soldier and a horse. They identified 32 types of pollen and found that the two items had different pollen signatures – indicating they were made in separate locations. Several ancient kilns have previously been discovered in this region of China and the new research may help trace the origins of the figures, reported BBC News.

Scientists have identified the world’s only known example of “semi-identical” twins. The toddlers were conceived as a result of two sperm fertilising a single egg that then split to form two embryos. Each stage is itself unlikely, so scientists do not expect to discover another rare case like this – these twins only came to the attention of scientists because one had ambiguous genitalia.

‘Their similarity is somewhere between identical and fraternal twins,’ commented Vivienne Souter, a genetist who investigated the case, in the Times.

And finally...

It’s a staple part of many of our diets, but it hardly has a healthy reputation. Now, however, food chemists have been working to give pizzas a nutrition makeover. By varying the baking temperature and time, they have discovered that they can increase the level of antioxidants in the pizza base. For example, cooking at 290 rather than 200 degrees celsius led antioxidants to increase by as much as 82 per cent. A longer fermentation time before baking also raised antioxidant levels.

Professor Lucy Yu said in the Guardian: ‘Antioxidants are considered beneficial to health because they protect important biological molecules such as DNA, lipids and enzymes from oxygen free radicals.

‘We’re not trying to make junk food more healthy, we’re providing hard scientific data so people who bake can improve the food they make.’

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