11 Nov
Events of Interest and Analyses, A Foreign Perspective
News
News
*********************
Deadly blast in central KarachiLarge explosion hits Criminal Investigation Department in Pakistani city, killing at least 25 people and injuring 35. |
||
|
******************************** Cholera reaches Haiti quake camps
|
| Aung San Suu Kyi’s lawyers said she plans to hold a press conference if she is freed without restrictions [AFP] |
A Myanmar court has rejected an appeal by the country’s detained opposition leader against her house arrest, amid hopes she will be released.
It was the third and final appeal by Aung San Suu Kyi, 65, who has spent most of the last 20 years locked up in her home……………………..
************************
Bomb ‘timed to explode over US’Forensic evidence shows parcel from Yemen was timed to detonate when jet would have been in US airspace, UK police say.
|
**********************
World
Showdown looms as leaders head to G20 summit
Nigel Morris: World leaders flew into South Korea last night to meet and try to avert a ‘currency war’.
- Aid workers held captive in payment row new
- Sun sets on US influence in Iraq as deal on new government looms
- Tea Party feels the pressure as counting begins in Alaskan poll
***********************************
The secrets of evolution unearthed in Highlands
By Steve Connor, Science Editor, Thursday, 11 November 2010
Independent MindsThe key moment in the history of life on Earth – the tipping point at which there was enough oxygen in the atmosphere to support the evolution of complex animals and plants – occurred about 400 million years earlier than previously thought, a study has found.
Geologists studying rocks in Scotland believe that oxygen – the vital element for energy-hungry life forms – began to rise to useful concentrations in the Earth’s atmosphere about 1.2 billion years ago rather than 800 million years ago, which was suggested by previous studies.
The discovery pushes back the point at which complex organisms could have begun to evolve from the simple microbes that had inhabited the planet for much of its history. But it raises the question: what was the ultimate spark that ignited the evolutionary explosion of life, leading to the immense diversity of species today?
Although the earliest fossil evidence of life on Earth goes back 3.8 billion years, for about 3 billion years of this time, living organisms consisted of simple microbes no more complex than “green slime”. It was only relatively recently – less than 1 billion years ago – that life began to evolve into symmetrical, multicellular organisms with complex body plans.
“Our geochemical analyses have provided a clear signal that levels of oxygen in the atmosphere had increased to levels critical to the evolution of complex life – from which we ourselves emerge – much earlier than has been previously proven to date,” said Adrian Boyce, of the Scottish Universities Environmental Research Centre in Glasgow.
“This opens the door to a new understanding of the evolution of our planet’s atmosphere and the life it sustains,” he added. The study, published in the journal Nature, analysed the chemical signatures of bacteria found in rocks near Lochinver in the north-west Highlands of Scotland, which showed that oxygen levels must have increased 1.2 billion years ago to allow certain sulphur-using microbes to exist in high numbers.
“Investigations revealed that these bacteria, which on a basic level use sulphur to obtain energy, were also using oxygen in a much more complex and efficient chemical reaction in order to generate their energy and survive,” said Professor John Parnell of Aberdeen University, who led the research team.
He added: “Evidence of this chemical reaction tells us that the levels of oxygen in the atmosphere were at this key point for evolution, at this much earlier stage in Earth’s history.
“Our findings, which shift this key point in the evolution of life on Earth to a much earlier date than previously proven, will give impetus to further investigations into the timescale of the development of complex life, which followed this event,” he said.
%d bloggers like this: