Après la privatisation du ravitaillement de la Station spatiale et bientôt du transport d"astronautes, la Nasa va statuer sur une autre demande : l"ancien directeur de l"agence spatiale américaine, qui était chargé du programme de l"ISS, veut y amarrer son propre module, qu"il louera pour des…


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Bientôt un module privé sur la Station spatiale pour la science et le tourisme

Le génome du tournesol vient d"être intégralement séquencé par des équipes françaises. Cette cartographie permettra d"optimiser les croisements dans les programmes de sélection variétale, explique l"Institut national de la recherche agronomique (Inra).


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Le génome du tournesol, plus grand que celui de l"Homme, enfin décrypté

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Cozmo, le robot jouet doté d"une intelligence artificielle

Comment est né le couple de trous noirs dont la fusion a généré l"onde gravitationnelle détectée en septembre 2015 par Ligo ? Des simulations numériques apportent peut-être la réponse, supposant qu"il s"est formé à partir des premières étoiles apparues il y a plus de 11 milliards d"années. Si…


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Ligo pourrait détecter mille fusions de trous noirs... par an

De plus en plus d"enfants développent des précirrhoses hépatiques avec des lésions qui n’étaient observées que chez les malades alcooliques. Environ 250 spécialistes réunis en congrès à l’Institut Pasteur de Paris tirent la sonnette d’alarme.


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Obésité infantile : trop de maladies du foie chez les enfants

Les internautes se moquent du rétropédalage de Boris Johnson (et c"est très drôle)Matthieu Balu30 juin 2016RebloguerPartagerTweeterÉpinglerEnvoyer

Les internautes se moquent du rétropédalage de Boris Johnson (et cLes internautes se moquent du rétropédalage de Boris Johnson (et cVoir les photos
Les internautes rivalisent d"imagination pour se moquer de Boris Johnson

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BREXIT – Ce n"est pas nouveau: avec son style ébouriffé, Boris Johnson est depuis longtemps la source de moqueries. Mais sa décision, le 30 juin, de ne pas briguer la tête d"un nouveau gouvernement britannique a créé chez les internautes une vague de créativité hilarante, à découvrir dans la vidéo en tête de cet article.


Avec des gif montrant en général des glissades, des chutes et autres ratés, les internautes laissent clairement paraître leur sentiments quant au choix du maire de Londres. Cette reculade, pour celui qui était la figure de proue du camp du Brexit, est ridiculisée sans ambiguïté. D"autres, à l"image d"Ewan Mc Gregor, l"ont prise avec moins d"humour.


Retrouvez cet article sur le Huffington Post
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Les internautes se moquent du rétropédalage de Boris Johnson (et c"est très drôle)



Wild Things


The weird and wonderful in the natural worldSarah Zielinski Wild Things Animals Sneaky male fiddler crabs entrap their mates by Sarah Zielinski 7:59am, June 30, 2016 banana fiddler crab

A male banana fiddler crab raises his large claw to try to lure a female to mate. A new study finds that some males take a more sinister approach to mating and trap females in their burrows.


Tanya Detto, Copyright Pat Backwell (CC-BY)


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Among people, a man stepping aside to let a woman pass through a door first is seen as a gentlemanly — if a bit old-fashioned — act. Among banana fiddler crabs, though, this behavior is a trap — one that lets a male crab coerce a female into a mating she may not have preferred.


To catch the attention of a female and lure her into his burrow, a male banana fiddler crab stands outside the entrance to his cave and waves the larger of his two claws. A female will look him over and consider his size, the color of his claw and how he’s waving it. If she likes what she sees, she’ll approach him. She might decide to enter his burrow and check it out, and once inside, she might stick around for mating if she thinks that the burrow has the right conditions for rearing her embryos.


When a female approaches a male and his burrow, most males enter first, letting their potential mate follow him down. But many male crabs take another approach, stepping aside and following her into the lair — letting a male trap the female inside and mate with her, researchers report June 15 in PLOS ONE.


Christina Painting of the Australian National University in Canberra and colleagues observed banana fiddler crabs in Darwin, Australia, during two mating seasons, watching what happened as males waved their claws and females made their choice. When a female was interested in a male, the guys entered the burrow first 32 percent of the time. While females were more likely to enter a burrow if a male entered first (71 percent versus only 41 percent when the guy stepped aside), the trapping strategy was more successful in getting a mating out of the meeting. When the male followed the female in, 79 percent of females stuck around the mate. But waiting for her to follow resulted in a pairing only 54 percent of the time.


“The results strongly suggest that entering a male’s burrow first reduces the probability that a female will leave the burrow after sampling it since females are effectively trapped underground in the narrow burrow shaft when the male follows her in,” the researchers write.


So why would a female ever enter a burrow first if there were the possibility that she would be trapped inside and coerced into mating? Perhaps this might give the female a chance to test the male’s strength, the researchers suggest. If she can successfully fight her way out, then the male was obviously not worthy of her attention. Or it is possible that this is just a type of courtship behavior in which no coercion is actually happening. It’s difficult to know exactly what’s going on underground.


This isn’t the first time that the males of a fiddler crab species have been found behaving in what we might consider an ungentlemanly fashion. Males of other species have been found trapping, herding, startling and capturing females in their attempts to coerce a mating. And some male sand bubbler crabs, the researchers note, have even been found behaving somewhat like pirates of the sand-mud flats: Males have been spotted capturing female crabs, carrying them back to their burrows and forcing them into their underground lairs for mating.


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Sneaky male fiddler crabs entrap their mates