Eureka!

Why dolphins are having to squeak up

Dolphins use high-pitched whistles to communicate and to hunt using echolocation, like bats do. So it’s worrying news that human activity, such as shipping and drilling, is raising underwater noise levels. According to new research by the University of Bristol, dolphins are having to compensate for the rising noise pollution by making their calls longer and louder so that they can still be heard by other dolphins.

This tiny robot can turn to liquid and then re-form!

Scientists have invented something that looks and sounds as if it comes from a science-fiction movie: a tiny shape-shifting robot that can melt into a liquid and then reform to become solid again.

The robot, which is just 1 mm tall and shaped like a LEGO figure, is made from a mixture of a liquid metal called gallium and microscopic magnetic particles. This means that when the scientists pass a magnetic field through the robot’s body, its temperature increases, causing it to melt.

After the robot has melted into a liquid puddle, the scientists use magnetic fields to pull it between the bars of a metal cage. Next, the scientists switch off the magnetic field, which cools the liquid robot, causing it to regain its previous strength and solidity. switched off, the robot cools, turning solid again. If the liquid is flowed into a mould, the robot will re-form into its original shape, as it does in the photo.

Scientists think that robots able to switch between solid states and liquid states in this way could one day be used to deliver medicine inside the body, or to replace a lost screw on a spaceship by flowing into the missing screw’s place as a liquid and then turning solid to become the replacement screw!

Have scientists spotted a space bear on Mars?

Look at the image below. Can you make out the face of a friendly bear? The photo was taken by astronomers at the University of Arizona in the United States using highresolution cameras on board a NASA spacecraft that is currently orbiting Mars. So although it may look a bit like a bear, researchers have a more convincingly scientific explanation. They think that the bear’s eyes are likely to be two craters formed by asteroid impacts, while its snout is formed by a sloping and partially collapsed hill which might once have been a volcano. According to the researchers, the outline of the bear’s head could be caused by dust settling on a larger crater.

Girls lead the way at Lerwick’s Viking festival

The Up Helly Aa Viking festival has been held in the town of Lerwick on the Scottish island of Shetland for more than 140 years.

This year, however, saw an extra special celebration, as women and girls joined the torchlit procession through the streets of Lerwick for the very first time.

In previous years, only men and boys were allowed to take part in the procession. But after a long campaign to persuade the festival to treat male and female participants equally, the organisers agreed to change the rules.

As a result, dozens of girls, some of them dressed as Vikings, were able to lead

Giant ‘Toadzilla’ discovered in Australia!

Wildlife rangers in Queensland, Australia, have come across a gigantic toad which experts say could be the world’s biggest. The toad, which has been given the nickname ‘Toadzilla’, was as long as a human arm and weighed 2.7 kilograms, which is around the same weight as a brick.

‘I reached down and grabbed the cane toad and couldn’t believe how big and heavy it was,’ said ranger Kylee Gray, describing her surprising discovery. ‘A cane toad that size will eat anything that it can fit into its mouth – and that includes insects, reptiles and small mammals.’

Toads are an invasive, or non-native, species in Australia that were brought to Queensland by humans to control the local population of cane beetles. However, the toads spread uncontrollably and are now considered pests themselves. the way and carry flaming Viking torches as they marched through the town.

At the end of the torchlit procession, a replica Viking galley, or ship, is dramatically set on fire as a way of celebrating the Scottish island’s ancient Viking heritage.