The BA Science News Digest - 13 October 2006
In the news this week: the world moves into ecological overdraft, our wobbly orbit is blamed for cycles of mass extinction and a new species of mouse is discovered. Plus, software that can help expose forged paintings, and the search for the home of Odysseus.
Monday set a worrying record by becoming the day on which we started living beyond our ecological means. As the Guardian reported, it is the earliest date yet on which the global demand for resources has exceeded the rate at which ecosystems can replenish them. The sustainable development organisation Global Footprint Network calculated that this occurred two days later last year, and in 1995 didn’t occur until November 21.
In other news, the Earth’s orbit oscillations have been blamed for mass mammal extinctions, while rare embryo fossils have given a valuable insight into the evolution of complex life on Earth.
Nature reported on a study which looked at whether tiny changes in the Earth’s orbit could wipe out life. A team in the Netherlands studied 80,000 rodent teeth ranging from 24.5 to 2.5 million years old, from 132 different species. They found evidence for two different cycles of extinctions and emerging species, occurring at a frequency of either 2.4 million years or 1 million years. These were found to correspond to cycles in which the Earth’s orbit deviates from circular and the tilt of the Earth’s axis changes, respectively.
Meanwhile, reported the Guardian, a US team have looked inside rare fossilised embryos more than half a billion years old and seen structures that suggest the intricate cellular machinery found in modern organisms was already beginning to evolve. The fragile fossils, found in the Doushantuo Formation in south-central China, are dated between 550m and 635m years old. A technique called microfocus x-ray computed tomography enabled the scientists to look inside the embryos and build up images of internal cellular structures. They found both similarities and differences compared to modern embryos: they divided using the same process as modern embryos, but they did not appear to contain a blastocoel (a fluid filled hole found in the centre of modern embryos), although this may simply not have survived the fossilisation process.
The question ‘what’s the minimum size a genome can be and still run a living organism?’ arises following the discovery of a bacterium whose genome contains just 182 genes and 159,662 base-pairs of DNA, making it by far the smallest genome on record. Science reports that the symbiotic bacterium, Carsonella ruddii, which lives within sap-feeding insects, has already lost some of the genes essential for independent bacterial life. It survives only because the host insect helps out with essential proteins.
A new species of mouse – thought to be the first European mammal discovered in 100 years – has been identified in Cyprus, reported the Times. The observant UK scientist responsible, who was on the island comparing Stone Age mouse teeth to modern varieties when he made his finding, has named the new species Mus cypriacus. It has a larger head, ears, eyes and teeth than previously known European mice.
The Independent reported the good news that a targeted rabies vaccination campaign may have saved the Ethiopian Wolf, one of the rarest animals in the world, from imminent extinction. With only approximately 500 of the wolves remaining following a rabies outbreak in 2003 that wiped out up to three-quarters of the population, the animal was in a precarious position. Computer modelling indicates that the campaign to vaccinate the most vulnerable animals has ensured a more secure short-term future for the species.
Once again, science impacts on the world of art…
Software has been developed that could help reveal forged paintings, reported the Guardian. Using a library of characteristics, such as brushstrokes, colours and canvas-type, obtained through high-resolution scans of paintings, the software has built up unique artist profiles. Comparison of paintings with these artistic “fingerprints” will help experts to determine whether they are authentic or fake much more quickly than at present.
And finally….
BBC News revealed that a group of UK scientists plan to test whether Homer got his geography right in the epic poem, the Odyssey. Challenging cherished ideas on Greek mythology, the geologists, working together with classicists and archaeologists, have proposed an alternative site for Ithaca, the home of Odysseus.
Arguing that the currently proposed site, the island of Ithaki, doesn’t fit descriptions within the poem, the geologists sank a borehole this week to test an alternative location. Their alternative, first proposed in a 2005 book by Robert Bittlestone, demands that the sea once flowed through a tight channel that joins Paliki to Kefalonia. The channel is now 180m above sea level at its highest point and they will need to find evidence of loose aggregates of rock and debris throughout the 100m-plus borehole in order to support their hypothesis that this rapid landscape change came about via a colossal infall of rock from surrounding hills.
Monday set a worrying record by becoming the day on which we started living beyond our ecological means. As the Guardian reported, it is the earliest date yet on which the global demand for resources has exceeded the rate at which ecosystems can replenish them. The sustainable development organisation Global Footprint Network calculated that this occurred two days later last year, and in 1995 didn’t occur until November 21.
In other news, the Earth’s orbit oscillations have been blamed for mass mammal extinctions, while rare embryo fossils have given a valuable insight into the evolution of complex life on Earth.
Nature reported on a study which looked at whether tiny changes in the Earth’s orbit could wipe out life. A team in the Netherlands studied 80,000 rodent teeth ranging from 24.5 to 2.5 million years old, from 132 different species. They found evidence for two different cycles of extinctions and emerging species, occurring at a frequency of either 2.4 million years or 1 million years. These were found to correspond to cycles in which the Earth’s orbit deviates from circular and the tilt of the Earth’s axis changes, respectively.
Meanwhile, reported the Guardian, a US team have looked inside rare fossilised embryos more than half a billion years old and seen structures that suggest the intricate cellular machinery found in modern organisms was already beginning to evolve. The fragile fossils, found in the Doushantuo Formation in south-central China, are dated between 550m and 635m years old. A technique called microfocus x-ray computed tomography enabled the scientists to look inside the embryos and build up images of internal cellular structures. They found both similarities and differences compared to modern embryos: they divided using the same process as modern embryos, but they did not appear to contain a blastocoel (a fluid filled hole found in the centre of modern embryos), although this may simply not have survived the fossilisation process.
The question ‘what’s the minimum size a genome can be and still run a living organism?’ arises following the discovery of a bacterium whose genome contains just 182 genes and 159,662 base-pairs of DNA, making it by far the smallest genome on record. Science reports that the symbiotic bacterium, Carsonella ruddii, which lives within sap-feeding insects, has already lost some of the genes essential for independent bacterial life. It survives only because the host insect helps out with essential proteins.
A new species of mouse – thought to be the first European mammal discovered in 100 years – has been identified in Cyprus, reported the Times. The observant UK scientist responsible, who was on the island comparing Stone Age mouse teeth to modern varieties when he made his finding, has named the new species Mus cypriacus. It has a larger head, ears, eyes and teeth than previously known European mice.
The Independent reported the good news that a targeted rabies vaccination campaign may have saved the Ethiopian Wolf, one of the rarest animals in the world, from imminent extinction. With only approximately 500 of the wolves remaining following a rabies outbreak in 2003 that wiped out up to three-quarters of the population, the animal was in a precarious position. Computer modelling indicates that the campaign to vaccinate the most vulnerable animals has ensured a more secure short-term future for the species.
Once again, science impacts on the world of art…
Software has been developed that could help reveal forged paintings, reported the Guardian. Using a library of characteristics, such as brushstrokes, colours and canvas-type, obtained through high-resolution scans of paintings, the software has built up unique artist profiles. Comparison of paintings with these artistic “fingerprints” will help experts to determine whether they are authentic or fake much more quickly than at present.
And finally….
BBC News revealed that a group of UK scientists plan to test whether Homer got his geography right in the epic poem, the Odyssey. Challenging cherished ideas on Greek mythology, the geologists, working together with classicists and archaeologists, have proposed an alternative site for Ithaca, the home of Odysseus.
Arguing that the currently proposed site, the island of Ithaki, doesn’t fit descriptions within the poem, the geologists sank a borehole this week to test an alternative location. Their alternative, first proposed in a 2005 book by Robert Bittlestone, demands that the sea once flowed through a tight channel that joins Paliki to Kefalonia. The channel is now 180m above sea level at its highest point and they will need to find evidence of loose aggregates of rock and debris throughout the 100m-plus borehole in order to support their hypothesis that this rapid landscape change came about via a colossal infall of rock from surrounding hills.
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