Science news digest – 28th January 2013
In the science news this week, dung beetles that are guided by the stars, heat from the cities is raising the temperature, Glasgow is to become a city for the future, and finally… dolphins form a raft to try and save a dying pod-mate.
Dung beetles use the stars to find their way
Scientists have shown that dung beetles use the Milky Way to guide them when rolling their balls of muck back to their lairs. It was already known that a number of other species use the stars to navigate, including birds, seals, and of course humans, but this is the first example of an insect doing so, reported BBC News.
Marie Dacke, from Lund University in Sweden, said: "The dung beetles are not necessarily rolling with the Milky Way or 90 degrees to it; they can go at any angle to this band of light in the sky. They use it as a reference."
Dung beetles like to run in straight lines in order to avoid bumping into a rival beetle, who would almost certainly try to steal their ball. Dacke had previously discovered that the beetles were able to keep a straight line by using the Sun, the Moon, and even the pattern of polarised light formed around these light sources.
However, what was surprising was the dung beetles’ ability to stay on a straight course even on a clear Moonless night.
To find out what was going on, she took the insects into the Johannesburg planetarium where she could control the type of star fields the beetles would be able to see.
She also blackened out the walls, so the beetles could use other landmarks as points of reference, which in the wild, might be a tree, for example.
She found that the beetles performed best when a perfect starry sky was above them, but that they also coped well when they could only see the bar of light from the Milky Way.
Dacke believes that is what the beetles use for their navigation rather than individual points of light, such as stars.
"These beetles have compound eyes," she told the BBC. "It's known that crabs, which also have compound eyes, can see a few of the brightest stars in the sky. Maybe the beetles can do this as well, but we don't know that yet; it's something we're looking at. However, when we show them just the bright stars in the sky, they get lost. So it's not them that the beetles are using to orientate themselves."
She’s also seen this in the wild when the Milky Way lays flat on the horizon at particular times of the year.
Big cities are the cause of extra heating
Researchers believe that urban life could be part of the reason why some areas of North America are seeing warmer winters, reported the Guardian.
The study found that the heat generated by large cities on the American east coast was causing winter warming thousands of miles away – in some cases as far away as the Canadian prairies.
In the remotest areas, temperatures rose by as much as 1 degree C, which produced changes in the jet stream and other atmospheric systems.
The researchers claimed to have found a similar pattern in Asia, where large urban areas resulted in warming in parts of Russia, northern Asia, and eastern China.
However, they also noted changes in the opposite direction in Europe, with the autumn temperatures lower by as much as 1 degree C.
The researchers noted that the extra heat from the large cities only accounted for a fraction of the warming from climate change, but that it did help explain the additional warming that was not predicted by current climate models.
"What really surprised us was that this energy use was a tiny amount, and yet it can create such a wide impact far away from the heat source," said Guang Zhang, a scientist at the Scripps Institution of Oceanography, who led the study. "We didn't expect it to be this much."
Glasgow will be the UK’s first “smart city”
A £24 million grant from the Technology Strategy Board (TSB) has been awarded to the city of Glasgow to help it become the UK’s first “smart city”, reported Wired.
The money is to be spent by the council to improve the quality of living for Glaswegian residents. Glasgow was chosen over 30 other UK cities that also made a bid for the grant.
Projects that are already on the table to be implemented across the city include, real-time traffic information, apps to check when buses and trains will arrive, and a pothole reporting service. There have also been discussions about including facial analysis for the city’s CCTV network, and energy use monitoring to improve the efficiency of electricity and gas delivery.
"Glasgow has some quite extreme challenges - it has the lowest life expectancy of any city in the UK for instance - and the hope is that if we bring together energy, transport, public safety and health it will make it more efficient and a better place to live," Scott Cain, the TSB's project leader for Future Cities.
"The thinking behind it is to have somewhere in the UK where firms can look at the efficiencies, the investments and how you can address the challenges of a city," he added. The data will also be made publicly available so that other cities will be able to benefit too.
Dolphins form raft to save another from drowning
For the first time, dolphins have been seen, and filmed, teaming up to try and save an injured pod member, reported New Scientist.
Kyum Park, from the Cetacean Research Institute in South Korea, surveyed a group of about 400 long-beaked common dolphins in the Sea of Japan in June 2008. Park and colleagues noticed that a group of roughly 12 dolphins were swimming very close together. They soon realised one of the females was in difficulties – tipping from side to side, and sometimes turning upside down.
The other dolphins crowded around it, often diving beneath it and supporting it from below, possibly to stop it from drowning.
Sadly, the dolphin died, but some of the helper group stayed with it until the body sank out of sight.
However, the researchers stated that this story does not necessarily mean that dolphins are selfless or can empathise with the pain of their kin.