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Domestic cats might be determined hunters, but they stick mostly to residential areas instead of venturing into parks and protected areas where coyotes roam. That’s the key finding from a North Carolina State University analysis of more than 2,100 sites – the first large-scale study of free-ranging cats in the U.S. published in the Journal of Mammalogy.

Why is it important to know where 74 million pet cats spend their time away from home?

El pasado 25 de abril Nepal fue golpeado por un terremoto de magnitud 7,8. Pero al igual que a los temblores, el país también es vulnerable al cambio climático, una combinación que hace más difícil construir la resiliencia y la preparación ante riesgos.

 Conforme las temperaturas medias se elevan en el sur de Asia, la temporada del monzón ha cambiado, dando lugar a precipitaciones más erráticas y aumentando el riesgo de inundaciones y deslizamientos de tierra que pueden cobrar vidas y la producción de alimentos.

An experiment originally designed to test the visual abilities of octopuses and cuttlefish has given University of Bristol researchers an unprecedented insight into the human ability to perceive polarized light – the super sense that most of us don’t even know we have. 

We are all familiar with colour and brightness, but there is a third property of light, the ‘polarization’, which tells us the orientation in which the light waves are oscillating. 

Dr Shelby Temple, a Research Associate from the Ecology of Vision Group in Bristol’s School of Biological Sciences and one of the study’s lead authors said: “Imagine a skipping rope represents a light wave travelling through space.  If you move the rope from side to side, the wave you make is horizontally polarized.  If you shake the rope up and down you create a vertically polarized wave. Generally, light is a mixture of polarizations, but sometimes – for example in parts of the sky, on your computer screen and in reflections from water or glass – a large percentage of the waves are oscillating in the same orientation and the light is strongly polarized.”

Trees that can tolerate soil pollution are also better at defending themselves against pests and pathogens. "It looks like the very act of tolerating chemical pollution may give trees an advantage from biological invasion", says Dr Frederic E. Pitre of the University of Montreal and one of the researchers behind the discovery. 

The day will officially be a bit longer than usual on Tuesday, June 30, 2015, because an extra second, or "leap" second, will be added. "Earth's rotation is gradually slowing down a bit, so leap seconds are a way to account for that," said Daniel MacMillan of NASA's Goddard Space Flight Center in Greenbelt, Maryland. Strictly speaking, a day lasts 86,400 seconds. That is the case, according to the time standard that people use in their daily lives - Coordinated Universal Time, or UTC. UTC is "atomic time" - the duration of one second is based on extremely predictable electromagnetic transitions in atoms of cesium. These transitions are so reliable that the cesium clock is accurate to one second in 1,400,000 years.