Scientists at the University of Liverpool have furthered understanding of the relationship between predator and prey in an experiment designed to understand butterfly defence mechanisms
Researchers observed the behaviour of Great-tits foraging for artificial prey to understand more clearly how a species evolves to protect themselves from predators.
Insects, such as butterflies, have bright contrasting colour patterns that indicate to predators that they are not likely to be palatable. In order to gain greater protection from predators, however, some butterflies evolve to imitate the warning signals of a more highly defended species - a phenomenon known as mimicry. Scientists at Liverpool, in collaboration with the University of Jyväskylä in Finland, tested which species of butterfly benefits the most from this technique.
40 years ago, Prof. Dr. Wolfgang Wiltschko was the first to prove that migrating robins use the Earth's magnetic field to direct themselves during migration. Their magnetic sensor showed them the course of the field lines of the Earth's magnetic field. This produces an inclination compass that reacts to the inclination of the Earth's magnetic field to the surface of the Earth, thus distinguishing between "pole-wards" (the side on which the field lines incline downwards) and "equator-wards" (the side on which they incline upwards). The inbuilt compass is additionally finely tuned to the field strength of the Earth's local magnetic field, but can also be flexibly adapted to other field strengths that the birds encounter in the course of migration. Since that time a compass of this kind has been found in more than 20 species of birds, the majority of them being those songbirds that undertake annual migration. An international working group under the direction of Wolfgang und Roswitha Wiltschko of Frankfurt University has now succeeded in demonstrating the presence of a magnetic sense of direction in domestic chickens as well.
A tropical storm in the South Pacific, the first of the year, is closing in on the northern coast of Vietnam, the country's national weather agency said Thursday.
According to Vietnam's Central Meteorological Service, the center of Tropical Storm Toraji at 7 a.m. local time (midnight GMT) was in the northern part of the Gulf of Tonkin, about 125 miles off the Vietnamese coast.
The storm is heading toward the coast at about 10mph, with sustained winds of up to 45mph, and is expected to hit Vietnam Friday if it remains on its current path.
Meteorologists issued a warning of potentially devastating heavy rains, flooding, tornadoes and mudslides.
Coastguards today rescued 110 children who were swept out to sea off the east coast of Ireland during a junior regatta.
A major rescue operation began after a sudden squall capsized 91 boats taking part in the event, off the seaside town of Dun Laoghaire in County Dublin.
Around 20 children were initially feared missing, but the coastguard said all had been plucked from the water less than a mile from shore.
A huge wave in Daytona Beach, Fla., crashed over a fireworks barge Wednesday night, forcing officials to cancel the city's annual Fourth of July show.
Officials said the wave hit the barge before 9 p.m. and washed more than half of the pyrotechnics off the vessel and into the water.
AFPThu, 05 Jul 2007 11:02 UTC
Rescuers pulled more bodies, including children, on Thursday from the wreckage of a bus swallowed by a landslide in Mexico which may have killed up to 60 people, local authorities said.
· Evacuated families fill city's hotels and B&Bs
· Prince boards rescue boat to view stricken village
Flood rescue plans for Britain's worst affected city will be announced today when ministers visit Hull, where 30,000 people - three-quarters of the national figure - had to leave their homes at the height of the crisis and an estimated one in every five houses has been damaged.
Only 15 of the city's 105 schools escaped and millions of pounds will be needed to repair day care centres, libraries and leisure complexes swept by 10cm (four inches) of rain, which swamped drains, killing two people.
AFPTue, 03 Jul 2007 20:39 UTC
The death toll from rains battering India rose to 61 as the downpour flooded states amid forecasts that the savage monsoon was likely to gain fury this week, officials said Tuesday.
Seventeen more deaths reported from Gujarat and West Bengal took to 294 the number of people killed in rain-related accidents so far this year, they said.
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| ©AFP/Sam Panthaky
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| This picture taken from inside and Ahmedabad Fire Services rescue vehicle shows vehicles struggling to pass a section of submerged highway at Dhanduka, some 90 Kms from Ahmedabad.
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Floods and landslides killed 30 people in a central China province, with the rain-swollen Yangtze River that cuts through the province at dangerously high levels, a government Web site and state media said Tuesday.
The flooding in Hubei province also left nine people missing, destroyed 53,400 homes and caused almost 800 million yuan (about US$100 million; €74 million) in losses, Xinhua News Agency reported.
APWed, 04 Jul 2007 14:35 UTC
Nevada sizzled on Wednesday as temperatures approached record highs and forecasters warned of even hotter conditions through the end of the week.
The National Weather Service issued a heat advisory for western Nevada and the eastern Sierra, where temperatures were expected to top the century mark through Friday.
