- Email: [email protected]
How planet Earth turned green
This week–
Public Lecture Tuesday 12 December at 6.30pm Admission free – no tickets or advance booking required. Doors open at 5.45pm Royal Society events are frequently broadcast on the web. Visit the video archive at www.royalsoc.ac.uk
The Royal Society 6-9 Carlton House Terrace, London SW1Y 5AG Tel: 020 7451 2581 Email: [email protected] Registered Charity No 207043
14 | NewScientist | 2 December 2006
061202_N_p14_p15.indd 14
Professor Ziauddin Sardar The Qur’an and the traditions of the Prophet Muhammad place great importance on science. Why is science so conspicuously absent from Muslim societies today? Ziauddin Sardar argues that science belongs at the very heart of Islamic culture and the survival of Muslim civilisation itself is intrinsically linked to its troubled relationship with science. Supported by The John Templeton Foundation.
based photosynthesis, which is more efficient than its anaerobic form. Such organisms would then have generated more oxygen for the atmosphere. This wouldn’t be the first major evolutionary advance linked to a snowball Earth. Multicellular life proliferated soon after another such episode ended 630 million years ago or so. However, Jim Kasting of Penn State University at University Park, a specialist in the origin and evolution of Earth’s atmosphere, isn’t convinced by this scenario. One key sticking point for him is the presence of sterols in 2.7-billion-year-old rocks – compounds only made by living cells in the presence of oxygen. If the sterol results are right, and that is by no means certain, then these rocks pre-date the snowball Earth by 400 million years. Back to the drawing board then to understand the history of oxygen and photosynthesis. ●
From The New Scientist, 6 December 1956
G IN
50 YEARS
IST
Islam and science: beyond the troubled relationship
“Thawing of snowball Earth set off the chain of events that led to oxygen-tolerant marine organisms and photosynthesis”
Last summer, Englishman John Jewell succeeded in scaling and then surveying part of a very unusual ice formation at Quenamari, high in the Peruvian Andes. Jewell, who is a member of the Himalaya Club, has just returned from the trip during which he spent some days studying the ice plateau, which is about 12 miles long and 2 to 3 miles wide. It is several hundred feet thick and drops precipitously on all sides to the level of the flat desert land which surrounds it. The strange feature of this ice formation is that it exists apparently without fresh supplies of moisture in the middle of a region which is entirely free from ice and snow for most of the year despite its altitude of about 18,000 feet above sea level. No glacier feeds this ice; no high mountain peaks are near enough to snatch rain from the clouds to water it. It is unique – so glaciologists say – and its existence remains a mystery. Until Jewell took his small party climbing in this little-explored part of mountainous Peru, no one had inspected the ice plateau thoroughly, although several climbers in the Cordillera de Carabaya had been struck by the glistening patch of ice along the horizon 20 miles away. Although the world’s ice is to be reviewed during the course of the 1957 International Geophysical Year, the Quenamari ice plateau is not included in the glaciologists’ programme. This is a pity because the reasons why such a phenomenon is able to exist would enhance our knowledge of the conditions under which ice can form and maintain itself.
NT
WE MAY owe our green Earth to a big freeze that covered the entire planet in thick sheets of ice 2.3 billion years ago. As this “snowball” Earth thawed, it released strong oxidants into the oceans and atmosphere for the first time, setting off the chain of events that led to oxygen-tolerant marine organisms and photosynthesis as we know it today. The evolution of efficient, oxygen-based photosynthesis has been hard to explain. Primitive forms gathered energy from light by using it to free electrons from
sulphur and iron in an oxygenfree environment. Oxygenic photosynthesis, which involves freeing electrons from water, takes more energy and produces oxygen. But oxygen was deadly to most primitive life on Earth. “The first organisms to do this would die,” says Hyman Hartman of the Massachusetts Institute of Technology. So how did organisms evolve oxygen tolerance? Hartman discussed the problem with Yuk Yung, a geobiologist at the California Institute of Technology in Pasadena and his colleagues, and they started to focus on the
‘Water free’ glacier in the Andes
AT
JEFF HECHT
THIS WEEK 50 YEARS AGO
CELEBR
How planet Earth turned green
role of hydrogen peroxide (H2O2). Ultraviolet light from the sun produces H2O2 when it hits water molecules. Today, sunlight destroys the peroxide as it forms. However, if UV light penetrated the surface of a glacier, small amounts of peroxide would have been trapped in the glacial ice for long periods, says Joe Kirschvink of Caltech. Indeed, H2O2 has been spotted on Jupiter’s icy moon Europa. The surface of an ice sheet would have been very similar on a primitive Earth that lacked an oxygen-rich atmosphere and a protective ozone layer. The researchers calculated that a thaw would have released the peroxide into the oceans and atmosphere, producing oxygen. The water would have diluted the harmful oxidants enough for primitive organisms to survive and evolve protective enzymes. Cells could then evolve oxygen-
OF N E W S C
IE
www.newscientist.com
27/11/06 4:24:04 pm
Public Lecture Tuesday 12 December at 6.30pm Admission free – no tickets or advance booking required. Doors open at 5.45pm Royal Society events are frequently broadcast on the web. Visit the video archive at www.royalsoc.ac.uk
The Royal Society 6-9 Carlton House Terrace, London SW1Y 5AG Tel: 020 7451 2581 Email: [email protected] Registered Charity No 207043
14 | NewScientist | 2 December 2006
061202_N_p14_p15.indd 14
Professor Ziauddin Sardar The Qur’an and the traditions of the Prophet Muhammad place great importance on science. Why is science so conspicuously absent from Muslim societies today? Ziauddin Sardar argues that science belongs at the very heart of Islamic culture and the survival of Muslim civilisation itself is intrinsically linked to its troubled relationship with science. Supported by The John Templeton Foundation.
based photosynthesis, which is more efficient than its anaerobic form. Such organisms would then have generated more oxygen for the atmosphere. This wouldn’t be the first major evolutionary advance linked to a snowball Earth. Multicellular life proliferated soon after another such episode ended 630 million years ago or so. However, Jim Kasting of Penn State University at University Park, a specialist in the origin and evolution of Earth’s atmosphere, isn’t convinced by this scenario. One key sticking point for him is the presence of sterols in 2.7-billion-year-old rocks – compounds only made by living cells in the presence of oxygen. If the sterol results are right, and that is by no means certain, then these rocks pre-date the snowball Earth by 400 million years. Back to the drawing board then to understand the history of oxygen and photosynthesis. ●
From The New Scientist, 6 December 1956
G IN
50 YEARS
IST
Islam and science: beyond the troubled relationship
“Thawing of snowball Earth set off the chain of events that led to oxygen-tolerant marine organisms and photosynthesis”
Last summer, Englishman John Jewell succeeded in scaling and then surveying part of a very unusual ice formation at Quenamari, high in the Peruvian Andes. Jewell, who is a member of the Himalaya Club, has just returned from the trip during which he spent some days studying the ice plateau, which is about 12 miles long and 2 to 3 miles wide. It is several hundred feet thick and drops precipitously on all sides to the level of the flat desert land which surrounds it. The strange feature of this ice formation is that it exists apparently without fresh supplies of moisture in the middle of a region which is entirely free from ice and snow for most of the year despite its altitude of about 18,000 feet above sea level. No glacier feeds this ice; no high mountain peaks are near enough to snatch rain from the clouds to water it. It is unique – so glaciologists say – and its existence remains a mystery. Until Jewell took his small party climbing in this little-explored part of mountainous Peru, no one had inspected the ice plateau thoroughly, although several climbers in the Cordillera de Carabaya had been struck by the glistening patch of ice along the horizon 20 miles away. Although the world’s ice is to be reviewed during the course of the 1957 International Geophysical Year, the Quenamari ice plateau is not included in the glaciologists’ programme. This is a pity because the reasons why such a phenomenon is able to exist would enhance our knowledge of the conditions under which ice can form and maintain itself.
NT
WE MAY owe our green Earth to a big freeze that covered the entire planet in thick sheets of ice 2.3 billion years ago. As this “snowball” Earth thawed, it released strong oxidants into the oceans and atmosphere for the first time, setting off the chain of events that led to oxygen-tolerant marine organisms and photosynthesis as we know it today. The evolution of efficient, oxygen-based photosynthesis has been hard to explain. Primitive forms gathered energy from light by using it to free electrons from
sulphur and iron in an oxygenfree environment. Oxygenic photosynthesis, which involves freeing electrons from water, takes more energy and produces oxygen. But oxygen was deadly to most primitive life on Earth. “The first organisms to do this would die,” says Hyman Hartman of the Massachusetts Institute of Technology. So how did organisms evolve oxygen tolerance? Hartman discussed the problem with Yuk Yung, a geobiologist at the California Institute of Technology in Pasadena and his colleagues, and they started to focus on the
‘Water free’ glacier in the Andes
AT
JEFF HECHT
THIS WEEK 50 YEARS AGO
CELEBR
How planet Earth turned green
role of hydrogen peroxide (H2O2). Ultraviolet light from the sun produces H2O2 when it hits water molecules. Today, sunlight destroys the peroxide as it forms. However, if UV light penetrated the surface of a glacier, small amounts of peroxide would have been trapped in the glacial ice for long periods, says Joe Kirschvink of Caltech. Indeed, H2O2 has been spotted on Jupiter’s icy moon Europa. The surface of an ice sheet would have been very similar on a primitive Earth that lacked an oxygen-rich atmosphere and a protective ozone layer. The researchers calculated that a thaw would have released the peroxide into the oceans and atmosphere, producing oxygen. The water would have diluted the harmful oxidants enough for primitive organisms to survive and evolve protective enzymes. Cells could then evolve oxygen-
OF N E W S C
IE
www.newscientist.com
27/11/06 4:24:04 pm