The Science News Digest - 17 April 2009
In the science news this week: an ancient Antarctic ecosystem that could help explain ice-age life, discovery of an all-female ant species, and mischievous gadgets...
Scientists from more than 100 labs around the world are gearing up to take part in a DIY competition to build a machine from biological parts, reported the Guardian. The last of the teams were registering this week, and will spend three months from June building their machines.
In its sixth year, the aim of the International Genetically Engineered Machine competition is to ‘take the basic building blocks of life and turn them into useful technology’. Components can be ordered from the Massachusetts Institute of Technology’s registry – which already contains about 3,200 parts. Any new parts used must be deposited in the registry when the competition is over.
The competition can yield interesting ideas. Last year, for example, a team from the University of Heidelberg in Germany conducted a project named ‘E.colicense to kill ‘. They re-engineered E.coli bacteria to home in on dangerous pathogens and then kill both themselves and the nearby pathogens by releasing a natural toxin. The team has since designed E.coli to hunt down cancer cells and destroy tumours in mice.
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BBC News reported that researchers have discovered an all-female ant species that is the first ever shown to have dispensed entirely with sexual reproduction. The Amazonian ant instead reproduces asexually by cloning the queen.
Dr Anna Himler’s interest in the species Mycocepurus smithii was first sparked by its skill at cultivating various different fungal crops for food. But further investigation by the University of Arizona biologist and her team uncovered an unusual sex bias. A battery of tests failed to uncover any males and DNA ‘fingerprinting’ showed that members of colonies were all clones of the colony’s queen. In addition, dissection of the female insects revealed they were physically incapable of mating.
While asexual reproduction of males from unfertilised eggs is known in some insect species, asexual reproduction of females is ‘exceedingly rare in ants’.
This method of reproduction could be advantageous because ‘it avoids the energetic cost of producing males, and doubles the number of reproductive females produced each generation from 50 per cent to 100 per cent of the offspring,’ explained Dr Himler. However, it could leave the colony susceptible to disease because if one ant is susceptible to a parasite, for example, all the clones will be too.
Dr Himler and colleagues are now investigating how long ago the phenomenon evolved.
--------------------
A community of microbes trapped nearly half a kilometre beneath an Antarctic glacier for more than 1.5 million years has demonstrated the ability of life to survive in the most extreme environments. It may help explain how life persisted during the ‘snowball Earth’ period when the surface of the globe was almost entirely frozen over, and also raises the prospect that further such discoveries could be discovered in other inhospitable environments both on Earth and on other planets.
The microbes were discovered by analysis of very salty water flowing out of a crack in the Taylor Glacier in East Antarctica. These annual summer trickles of water have been named ‘Blood Falls’ because iron in the water stains the ice red.
The fact that the brine contained no oxygen indicated that it had been isolated from the atmosphere, but it was found to contain the genetic signatures of living microorganisms. DNA analysis suggested the microbes were closely related to modern-day marine microbes.
Trapped in total darkness with nothing but minerals and long-decayed organic matter, the microbes survived by ‘breathing’ iron to produce energy – using sulphur compounds as chemical catalysts. The research has been published in the journal Science. Read more in the Independent and New Scientist.
--------------------
Scientists analysing lake sediments in West Africa have discovered that the region is susceptible to a cycle of droughts and megadroughts. It appears that the infamous 1970s Sahel region drought that lasted several decades and killed over 100,000 people was actually a relatively ‘minor’ event, reported New Scientist.
Lake Bosumtwi is Ghana’s only natural lake, formed in an ancient meteorite impact crater. Lake levels are very dependent on rainfall, and sediments are laid down each year in precise layers as nothing lives at the bottom to disturb them.
A research team led by Tim Shanahan from the University of Texas studied relative amounts of different oxygen isotopes in layers within a sediment core taken from the lake, and were able to reconstruct 3,000 years of rainfall. The study, reported in the journal Science, revealed that droughts lasting several decades occurred every 30 to 60 years, and also that there was a pattern of more severe droughts lasting a century or more. The last of these megadroughts occurred from 1400 to 1750.
’It’s disconcerting,’ Professor Shanahan told BBC News. ‘It suggests we’re vulnerable to a longer-lasting drought than we’ve seen in our lifetime. If the region were to shift into one of these droughts it would be very difficult for people to adapt; and we need to develop an adaptation policy.’
--------------------
Other news in brief:
The government has released a list of 11 sites in England in Wales where new nuclear power stations could potentially be built. There will now be a month-long period of publication consultation.
(BBC News)
MI5, the UK’s domestic intelligence agency is recruiting a Chief Scientific Advisor to help combat terrorism and support counter-intelligence operations.
(BBC News)
According to a report by computer security firm McAfee, 62 trillion spam emails sent in 2008 resulted in carbon emissions equivalent to cars using 2 billion gallons of petrol.
(New Scientist)
The Pacific Gas and Electric Company, a leading American power company, has agreed to buy electricity from Solaren – a startup company that claims to have found a way to take advantage of space-based solar power. The company plans to launch solar panels into orbit, beam the energy back down to a depot in California as radio-frequency transmissions, and convert the energy to usable electricity.
(Guardian)
--------------------
And finally...
Do your furniture and gadgets fade into the background when they’re no longer shiny and new? Well someone may have come up with a solution to make you take more notice: attention-seeking objects.
James Pierce at Indiana University is designing ways for objects to periodically make their presence felt. He believes this approach will help to end our unsustainable habit of constantly buying new things to replace the old and ‘discourage thoughtless consumption of things’ by increasing our sense of attachment to our possessions.
Pierce presented his ideas recently at the Computer Human Interaction conference in Boston, reported New Scientist. Among his approaches is cheeky misbehaviour of objects – such as a lamp that gradually dims and needs to be shaken to wake it up again, and a clock that occasionally displays the wrong time before correcting itself with a message that it was just joking.
Personally, I’m not sure that I want to be wound up by my gadgets... but if it makes us stop and think before throwing them away when they get a bit old, maybe it’s not such a bad idea.
Scientists from more than 100 labs around the world are gearing up to take part in a DIY competition to build a machine from biological parts, reported the Guardian. The last of the teams were registering this week, and will spend three months from June building their machines.
In its sixth year, the aim of the International Genetically Engineered Machine competition is to ‘take the basic building blocks of life and turn them into useful technology’. Components can be ordered from the Massachusetts Institute of Technology’s registry – which already contains about 3,200 parts. Any new parts used must be deposited in the registry when the competition is over.
The competition can yield interesting ideas. Last year, for example, a team from the University of Heidelberg in Germany conducted a project named ‘E.colicense to kill ‘. They re-engineered E.coli bacteria to home in on dangerous pathogens and then kill both themselves and the nearby pathogens by releasing a natural toxin. The team has since designed E.coli to hunt down cancer cells and destroy tumours in mice.
--------------------
BBC News reported that researchers have discovered an all-female ant species that is the first ever shown to have dispensed entirely with sexual reproduction. The Amazonian ant instead reproduces asexually by cloning the queen.
Dr Anna Himler’s interest in the species Mycocepurus smithii was first sparked by its skill at cultivating various different fungal crops for food. But further investigation by the University of Arizona biologist and her team uncovered an unusual sex bias. A battery of tests failed to uncover any males and DNA ‘fingerprinting’ showed that members of colonies were all clones of the colony’s queen. In addition, dissection of the female insects revealed they were physically incapable of mating.
While asexual reproduction of males from unfertilised eggs is known in some insect species, asexual reproduction of females is ‘exceedingly rare in ants’.
This method of reproduction could be advantageous because ‘it avoids the energetic cost of producing males, and doubles the number of reproductive females produced each generation from 50 per cent to 100 per cent of the offspring,’ explained Dr Himler. However, it could leave the colony susceptible to disease because if one ant is susceptible to a parasite, for example, all the clones will be too.
Dr Himler and colleagues are now investigating how long ago the phenomenon evolved.
--------------------
A community of microbes trapped nearly half a kilometre beneath an Antarctic glacier for more than 1.5 million years has demonstrated the ability of life to survive in the most extreme environments. It may help explain how life persisted during the ‘snowball Earth’ period when the surface of the globe was almost entirely frozen over, and also raises the prospect that further such discoveries could be discovered in other inhospitable environments both on Earth and on other planets.
The microbes were discovered by analysis of very salty water flowing out of a crack in the Taylor Glacier in East Antarctica. These annual summer trickles of water have been named ‘Blood Falls’ because iron in the water stains the ice red.
The fact that the brine contained no oxygen indicated that it had been isolated from the atmosphere, but it was found to contain the genetic signatures of living microorganisms. DNA analysis suggested the microbes were closely related to modern-day marine microbes.
Trapped in total darkness with nothing but minerals and long-decayed organic matter, the microbes survived by ‘breathing’ iron to produce energy – using sulphur compounds as chemical catalysts. The research has been published in the journal Science. Read more in the Independent and New Scientist.
--------------------
Scientists analysing lake sediments in West Africa have discovered that the region is susceptible to a cycle of droughts and megadroughts. It appears that the infamous 1970s Sahel region drought that lasted several decades and killed over 100,000 people was actually a relatively ‘minor’ event, reported New Scientist.
Lake Bosumtwi is Ghana’s only natural lake, formed in an ancient meteorite impact crater. Lake levels are very dependent on rainfall, and sediments are laid down each year in precise layers as nothing lives at the bottom to disturb them.
A research team led by Tim Shanahan from the University of Texas studied relative amounts of different oxygen isotopes in layers within a sediment core taken from the lake, and were able to reconstruct 3,000 years of rainfall. The study, reported in the journal Science, revealed that droughts lasting several decades occurred every 30 to 60 years, and also that there was a pattern of more severe droughts lasting a century or more. The last of these megadroughts occurred from 1400 to 1750.
’It’s disconcerting,’ Professor Shanahan told BBC News. ‘It suggests we’re vulnerable to a longer-lasting drought than we’ve seen in our lifetime. If the region were to shift into one of these droughts it would be very difficult for people to adapt; and we need to develop an adaptation policy.’
--------------------
Other news in brief:
The government has released a list of 11 sites in England in Wales where new nuclear power stations could potentially be built. There will now be a month-long period of publication consultation.
(BBC News)
MI5, the UK’s domestic intelligence agency is recruiting a Chief Scientific Advisor to help combat terrorism and support counter-intelligence operations.
(BBC News)
According to a report by computer security firm McAfee, 62 trillion spam emails sent in 2008 resulted in carbon emissions equivalent to cars using 2 billion gallons of petrol.
(New Scientist)
The Pacific Gas and Electric Company, a leading American power company, has agreed to buy electricity from Solaren – a startup company that claims to have found a way to take advantage of space-based solar power. The company plans to launch solar panels into orbit, beam the energy back down to a depot in California as radio-frequency transmissions, and convert the energy to usable electricity.
(Guardian)
--------------------
And finally...
Do your furniture and gadgets fade into the background when they’re no longer shiny and new? Well someone may have come up with a solution to make you take more notice: attention-seeking objects.
James Pierce at Indiana University is designing ways for objects to periodically make their presence felt. He believes this approach will help to end our unsustainable habit of constantly buying new things to replace the old and ‘discourage thoughtless consumption of things’ by increasing our sense of attachment to our possessions.
Pierce presented his ideas recently at the Computer Human Interaction conference in Boston, reported New Scientist. Among his approaches is cheeky misbehaviour of objects – such as a lamp that gradually dims and needs to be shaken to wake it up again, and a clock that occasionally displays the wrong time before correcting itself with a message that it was just joking.
Personally, I’m not sure that I want to be wound up by my gadgets... but if it makes us stop and think before throwing them away when they get a bit old, maybe it’s not such a bad idea.
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