First Americans came from Iberia, not Siberia

First Americans came from Iberia, not Siberia

IN BRIEF Alberto Guglielmi/Getty NOW there is no excuse to avoid the gym: just one hour of exercise instantly changes your genes to boost the breakd...

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IN BRIEF

Alberto Guglielmi/Getty

NOW there is no excuse to avoid the gym: just one hour of exercise instantly changes your genes to boost the breakdown of fat. Juleen Zierath and Romain Barrès at the Karolinska Institute in Stockholm, Sweden, and colleagues looked for epigenetic changes – the addition of a methyl group to genes – in muscle cells during strenuous exercise. To do so, the team collected biopsies from the thigh muscles of eight men who led relatively sedentary lives, both before and after an hour of exercise. Several genes involved in fat metabolism that were methylated before the exercise lost their methyl group. Such demethylation allows genes to more easily make proteins, which suggests that more proteins involved in the breakdown of fat are being made after exercise, says Zierath. The group was surprised to see these effects happen so quickly. They think calcium, produced in muscle cells during exercise, may be involved since subjecting the same biopsies to caffeine – which also increases calcium in muscles – caused the same demethylation (Cell Metabolism, DOI: 10.1016/ j.cmet.2012.01.001). Unfortunately, you would get caffeine intoxication before gaining the same effects from coffee as an hour-long workout, says Zierath.

20 | NewScientist | 10 March 2012

When antimatter and matter make good bedfellows MATTER and antimatter don’t normally get on, annihilating in a blast of gamma rays if they so much as touch. Now the two may have been glimpsed peacefully coexisting. That would cement a 70-year-old theory and might even shore up qubits, the delicate bits in quantum computers. In 1937, Italian physicist Ettore Majorana was studying fermions, the class of particle that includes electrons and quarks, the building blocks of matter. Each fermion has an antimatter equivalent, which is oppositely charged.

An electron’s antiparticle, for instance, is the positively charged positron. Majorana proposed that a fermion with neither positive nor negative electric charge might have an antiparticle that was indistinguishable from the original, and represent matter and antimatter as a happy couple. Last week at the American Physical Society meeting in Boston, Leo Kouwenhoven of the Delft University of Technology in the Netherlands and colleagues produced tentative evidence for such a twosome.

Their Majorana particles are not free agents but collective excitations of electrons and “hole” states – absences of electrons – in nanoscale wires made of a semiconductor. The team saw a blip in the spectrum of energies in the nanowire that could only be the calling card of a pair of Majorana fermions. Qubits are vulnerable to losing information when buffeted by their environment. Majorana pairs would encode the same information over two sites, making them more robust. Heyward & Negri/AIMS

Exercise boosts fat-busting genes

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First Americans – Iberian not Siberian DID some of the first American settlers come from Europe rather than across the Bering land bridge from Siberia to Alaska, as most people believe? The controversial theory is advanced in Across Atlantic Ice, a book launched last week in the US. Co-authors Bruce Bradley of the University of Exeter, UK, and Dennis Stanford of the Smithsonian Institution in Washington DC claim that much of the north Atlantic Ocean was spanned by glaciers and ice floes during the last ice age. This bridge allowed early Europeans called the Solutreans to cross. “We’re using an analogy with Inuit, who expanded all across the Arctic with technologies no more sophisticated than those we know the Solutreans had,” says Bradley. Their key evidence is the discovery in the eastern US of 18,000 to 26,000-year-old tools with a Solutrean appearance. Other archaeologists are deeply sceptical of the theory, which has been circulating for a decade. Lawrence Straus of the University of New Mexico in Albuquerque argues that the first Americans come from Siberia and developed “Solutrean” tools independently.

Broken coral embryos form clone army CORALS turn a turbulent upbringing into an advantage. Although currents break up fragile coral embryos, each fragment can develop into a normal adult. Most corals on Australia’s Great Barrier Reef take part in mass spawnings. Their sperm and eggs fuse in the open water to form embryos that drift for days before settling onto substrate. But the free-floating embryos are vulnerable because – unlike most organisms – they don’t have a protective outer membrane, says Andrew Negri of the Australian

Institute of Marine Science in Townsville, Queensland. Negri found that 45 per cent of Acropora millepora embryos break apart in turbulence. This is good news for the coral, because each fragment survives and develops. The resulting larvae are smaller than usual, but they successfully settle and transform into corals (Science, DOI: 10.1126/science.1216055). Being able to make multiple offspring from a single fertilised egg is a boon for corals, says Rachel Jones of the Zoological Society of London, who was not involved with the work.