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Zoologger: Superfemale mice have secret male DNA
NASA/GSFC-SVS/SCIENCE PHOTO LIBRARY
IN BRIEF Double flood trouble for Europe
Moon’s radio glow can help keep Islamic dates in sync IS IT Ramadan yet? Muslim communities look for the new moon to decide, and radio waves could settle the matter. The Islamic calendar is based on lunar months, with sightings of the first sliver of the waxing moon marking the start of each month. It is possible to calculate when this thin crescent will theoretically be visible, but many Muslims will only accept visual confirmation. Religious authorities in each country conduct their own lunar observations, so cloudy skies can delay the start of a new month by a day or two in some countries relative to others. This means that Muslims around the
world can get slightly out of sync when marking festivals and the start and end of the holy month of Ramadan. Radio observations could bring calendars more into line, says a team led by Yaser Hafez at the King Abdulaziz City for Science and Technology, the Saudi Arabian science agency in Riyadh. Solar radiation bouncing off the moon creates a distinct glow for radio astronomers, even in cloudy conditions. Using a 3.7-metre radio telescope, the team could lock on to the moon’s signal as the first thin crescent appeared (MNRAS, doi.org/rpt). Traditionalists will probably prefer visual confirmation, says Khalid Shaukat, who runs the Islamic astronomy website moonsighting.com. But the team argues that its method is complementary and might help resolve matters in the event of a disputed sighting.
Tomboy mice have the most pups NEVER write off a rank outsider. A female mammal with a “male” chromosome should struggle to reproduce, but for female African pygmy mice, a male chromosome spells more offspring. Mus minutoides has three sex chromosomes. On top of the usual X and Y seen in other mammals, there is a modified X called X*. In 2010, Frédéric Veyrunes of the Institute of Evolutionary Sciences 14 | NewScientist | 8 March 2014
at the University of Montpellier in France realised the X* is “super-feminising”: it blocks the masculinising effect of the Y chromosome. So females can be XX, XX* or X*Y. Males are all XY. Now Veyrunes has found that X*Y females reproduce more than XX or XX*. They were more likely to have a litter during a six-month spell with a male, and had larger litters (Evolution, doi.org/rpr).
Yet one-quarter of a Y-female’s offspring die before birth – they inherit two Y chromosomes, one from each parent, so lack vital genes from the X chromosome. So why does a Y chromosome help a female reproduce? Part of the answer may be that males and Y-females are more likely to breed, because the females behave in a more “male” way. Lab studies offer some support for this. In that case, the Y-females’ secret may be being tomboys.
EUROPE’S politicians should stockpile waterproof boots. By 2050 big floods will swamp Europe twice as often as now, and annual costs may quintuple. Climate change is partly to blame, as is construction in flood zones. A new study by Brenden Jongman of the VU University in Amsterdam, the Netherlands, is the first to include floods that affect several river basins at once. His team fed data on peak river flows into climate models. They say major floods will hit Europe every 10 years by 2050, instead of every 16 years as now. Annual losses from floods, now at €4.9 billion, will reach €23 billion by 2050 (Nature Climate Change, doi.org/rqp). Climate change accounts for onethird of the extra losses. “This approach provides an important basis for a new way of carrying out continental-scale risk management,” says Hannah Cloke of the University of Reading, UK.
Super-rice defies a triple whammy FOR the first time, a single strain of genetically modified rice has been made that handles drought, salty soils and lack of fertiliser. The aim is to “climate-proof” rice farms in Asia and Africa. Drought costs $13 billion a year globally in crop losses, while salt costs $1 billion per year. Fertilisers often pollute nearby water. Some crops cope with single environmental stresses, but this rice is the first to handle three at once. It was made by Arcadia Biosciences in Davis, California, using genes from a type of cress, a soil bacterium and barley. In two years of trials, under each of the stresses the GM rice produced yields 12 to 42 per cent greater than the unmodified parent rice, according to Arcadia.
IN BRIEF Double flood trouble for Europe
Moon’s radio glow can help keep Islamic dates in sync IS IT Ramadan yet? Muslim communities look for the new moon to decide, and radio waves could settle the matter. The Islamic calendar is based on lunar months, with sightings of the first sliver of the waxing moon marking the start of each month. It is possible to calculate when this thin crescent will theoretically be visible, but many Muslims will only accept visual confirmation. Religious authorities in each country conduct their own lunar observations, so cloudy skies can delay the start of a new month by a day or two in some countries relative to others. This means that Muslims around the
world can get slightly out of sync when marking festivals and the start and end of the holy month of Ramadan. Radio observations could bring calendars more into line, says a team led by Yaser Hafez at the King Abdulaziz City for Science and Technology, the Saudi Arabian science agency in Riyadh. Solar radiation bouncing off the moon creates a distinct glow for radio astronomers, even in cloudy conditions. Using a 3.7-metre radio telescope, the team could lock on to the moon’s signal as the first thin crescent appeared (MNRAS, doi.org/rpt). Traditionalists will probably prefer visual confirmation, says Khalid Shaukat, who runs the Islamic astronomy website moonsighting.com. But the team argues that its method is complementary and might help resolve matters in the event of a disputed sighting.
Tomboy mice have the most pups NEVER write off a rank outsider. A female mammal with a “male” chromosome should struggle to reproduce, but for female African pygmy mice, a male chromosome spells more offspring. Mus minutoides has three sex chromosomes. On top of the usual X and Y seen in other mammals, there is a modified X called X*. In 2010, Frédéric Veyrunes of the Institute of Evolutionary Sciences 14 | NewScientist | 8 March 2014
at the University of Montpellier in France realised the X* is “super-feminising”: it blocks the masculinising effect of the Y chromosome. So females can be XX, XX* or X*Y. Males are all XY. Now Veyrunes has found that X*Y females reproduce more than XX or XX*. They were more likely to have a litter during a six-month spell with a male, and had larger litters (Evolution, doi.org/rpr).
Yet one-quarter of a Y-female’s offspring die before birth – they inherit two Y chromosomes, one from each parent, so lack vital genes from the X chromosome. So why does a Y chromosome help a female reproduce? Part of the answer may be that males and Y-females are more likely to breed, because the females behave in a more “male” way. Lab studies offer some support for this. In that case, the Y-females’ secret may be being tomboys.
EUROPE’S politicians should stockpile waterproof boots. By 2050 big floods will swamp Europe twice as often as now, and annual costs may quintuple. Climate change is partly to blame, as is construction in flood zones. A new study by Brenden Jongman of the VU University in Amsterdam, the Netherlands, is the first to include floods that affect several river basins at once. His team fed data on peak river flows into climate models. They say major floods will hit Europe every 10 years by 2050, instead of every 16 years as now. Annual losses from floods, now at €4.9 billion, will reach €23 billion by 2050 (Nature Climate Change, doi.org/rqp). Climate change accounts for onethird of the extra losses. “This approach provides an important basis for a new way of carrying out continental-scale risk management,” says Hannah Cloke of the University of Reading, UK.
Super-rice defies a triple whammy FOR the first time, a single strain of genetically modified rice has been made that handles drought, salty soils and lack of fertiliser. The aim is to “climate-proof” rice farms in Asia and Africa. Drought costs $13 billion a year globally in crop losses, while salt costs $1 billion per year. Fertilisers often pollute nearby water. Some crops cope with single environmental stresses, but this rice is the first to handle three at once. It was made by Arcadia Biosciences in Davis, California, using genes from a type of cress, a soil bacterium and barley. In two years of trials, under each of the stresses the GM rice produced yields 12 to 42 per cent greater than the unmodified parent rice, according to Arcadia.