Male bowerbirds grow a
garden to attract a mate :
Although the males didn't build the ir bowers in locations with abundant S. ellipticum, a year after construction the re were, on average, 40 of the plants near each. Birds with more plants nearby had more berries within their WHAT has green fingers but no hands? The bowerbird, bowers, which Madden has previously fou nd is the best if a new study is to be believed. Males appear to cultivate predictor of a male's mating success. Males may discard plants around the structures they build to attract a mate. shrivelled berri es outside the ir bowers ( Current Bio/ogy, Male spotted bowerbirds (Ptilonorhynchus maculatus) DOl: 10.1016/j.cub.2012.02.057). build structures, or bowers, from twigs before intricately decorating them with abjects to attract a female. One of the males' most desirable decorations is the berry of the Solanum ellipticum plant. The bowerbirds are th us shaping the distribution joah Madden of the University of Exeter, UK, and colleagues studied the distribution of S. ellipticum in an a rea of Queensland, Australia, inhabited by the birds. of the plants in the area- but is it cultivation? Madden acknowledges the results do not imply that the birds intentionally grow the plants. But he points out th at sorne hypotheses faveur similarly unintentional origins for hu man agriculture, suggesting the bowerbirds' activities cou Id just about fa li under th at definition.
Epigenetic changes linked with ageing :
SOME of the gene tic changes associated with ageing may be the re suit of epigenetics-which suggests they could be reversed. Molecules can attach to DNA, enhancing or preventing gene activation without changing the underlying genetic code. Such epigenetic changes are already suspected as factors in psychiatrie disorders, diabetes and cancer. They may also play a role in ageing. Jordana Bell ofKing's College London and colleagues looked at the DNA of 86 sets of twin sisters aged 32 to 8o, and discovered that 490 genes linked with ageing showed signs of epigenetic change through a process called methylation. "These genes were more likely to be methylated in the older th an the younger [sets of] twins," says Bell, suggesting that the epigenetic changes themselves might contribute to ageing (PLoS Genetics, DOl: 10.1371/journal. pgen.1002629 ). The next challenge is to establish when gene methylation occurs. lt can be triggered through lifestyle factors su ch as smoking, and environmental stresses. lt may one day be possible to develop enzymes that can remove the offending molecules from DNA and reverse methylationand sorne aspects of ageing.
Ci ut-microbe swap flips eating habits : EATEN too many pies? Biarne the microbes in your gut- they may be influencing how much you eat. In 2006, biologists found that the types ofbacteria in the guts of obese rats differed from th ose in non-obese rats. To find out more, Mihai Covasa and his colleagues at the French National Institute for Agricultural Research (INRA) in Paris swapped gut bacteria between obesity-prone and obesity-resistant rats. The obesity-resistant rodents proceeded to eat more and pile on the pounds. They also developed gut hormone levels typical of obesity-prone rodents. The se rats are a good model for human obesity- people, too, are either resistant or vulnerable to the condition. Understanding the gut flora associated with it may offerways to help control food intake, Covasa said this week at the Experimental Biol ogy 2012 meeting in San Diego, California.
Neutrino no-show spoilsraytheory:
THE failure by an Antarctic telescope to spot neutrinos has knocked down a major theory about the origin ofhigh-energy partiel es known as cosmic rays. Theorists had thought explosive bursts of gamma rays could be behind the co smic rays. So the IceCube telescope had been looking for neutrinos that ought to be produced at the same time. Finding no neutrinos is a se rio us blow because it rules out gamma ray bursts, says principal investigator Francis Halzen at the UniversityofWisconsin, Madison (Nature, DOI:10.1038/ natureuo68). So where do the cos mie rays come from? No body is sure, but attention will now shift to active galactic nuclei powered by supermassive black ho les.
Although the males didn't build the ir bowers in locations with abundant S. ellipticum, a year after construction the re were, on average, 40 of the plants near each. Birds with more plants nearby had more berries within their WHAT has green fingers but no hands? The bowerbird, bowers, which Madden has previously fou nd is the best if a new study is to be believed. Males appear to cultivate predictor of a male's mating success. Males may discard plants around the structures they build to attract a mate. shrivelled berri es outside the ir bowers ( Current Bio/ogy, Male spotted bowerbirds (Ptilonorhynchus maculatus) DOl: 10.1016/j.cub.2012.02.057). build structures, or bowers, from twigs before intricately decorating them with abjects to attract a female. One of the males' most desirable decorations is the berry of the Solanum ellipticum plant. The bowerbirds are th us shaping the distribution joah Madden of the University of Exeter, UK, and colleagues studied the distribution of S. ellipticum in an a rea of Queensland, Australia, inhabited by the birds. of the plants in the area- but is it cultivation? Madden acknowledges the results do not imply that the birds intentionally grow the plants. But he points out th at sorne hypotheses faveur similarly unintentional origins for hu man agriculture, suggesting the bowerbirds' activities cou Id just about fa li under th at definition.
Epigenetic changes linked with ageing :
SOME of the gene tic changes associated with ageing may be the re suit of epigenetics-which suggests they could be reversed. Molecules can attach to DNA, enhancing or preventing gene activation without changing the underlying genetic code. Such epigenetic changes are already suspected as factors in psychiatrie disorders, diabetes and cancer. They may also play a role in ageing. Jordana Bell ofKing's College London and colleagues looked at the DNA of 86 sets of twin sisters aged 32 to 8o, and discovered that 490 genes linked with ageing showed signs of epigenetic change through a process called methylation. "These genes were more likely to be methylated in the older th an the younger [sets of] twins," says Bell, suggesting that the epigenetic changes themselves might contribute to ageing (PLoS Genetics, DOl: 10.1371/journal. pgen.1002629 ). The next challenge is to establish when gene methylation occurs. lt can be triggered through lifestyle factors su ch as smoking, and environmental stresses. lt may one day be possible to develop enzymes that can remove the offending molecules from DNA and reverse methylationand sorne aspects of ageing.
Ci ut-microbe swap flips eating habits : EATEN too many pies? Biarne the microbes in your gut- they may be influencing how much you eat. In 2006, biologists found that the types ofbacteria in the guts of obese rats differed from th ose in non-obese rats. To find out more, Mihai Covasa and his colleagues at the French National Institute for Agricultural Research (INRA) in Paris swapped gut bacteria between obesity-prone and obesity-resistant rats. The obesity-resistant rodents proceeded to eat more and pile on the pounds. They also developed gut hormone levels typical of obesity-prone rodents. The se rats are a good model for human obesity- people, too, are either resistant or vulnerable to the condition. Understanding the gut flora associated with it may offerways to help control food intake, Covasa said this week at the Experimental Biol ogy 2012 meeting in San Diego, California.
Neutrino no-show spoilsraytheory:
THE failure by an Antarctic telescope to spot neutrinos has knocked down a major theory about the origin ofhigh-energy partiel es known as cosmic rays. Theorists had thought explosive bursts of gamma rays could be behind the co smic rays. So the IceCube telescope had been looking for neutrinos that ought to be produced at the same time. Finding no neutrinos is a se rio us blow because it rules out gamma ray bursts, says principal investigator Francis Halzen at the UniversityofWisconsin, Madison (Nature, DOI:10.1038/ natureuo68). So where do the cos mie rays come from? No body is sure, but attention will now shift to active galactic nuclei powered by supermassive black ho les.
Form : NewScientist 28 April 2012
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