14
SCIENCE FACTS
SCIENCE FACTS
How do honeybees return to their hives after travelling long distances in search of nectar ?
Communication , that is , transfer of information is essential for the survival of any living organism . Each and every organism has its own unique and remarkable way of communication . It is more effective when one animal responds to the signals sent out by another animal . Animals including insects ( for example , honey bee ) utilise chemical , tactile , visual and auditory signals as communicating methods with each other . Bees , the social insects have a powerful communication system among the individuals through their movements and odour cues . German Zoologist , Karl von Frisch , discovered the amazing communication system of honeybee about the source of food , distance and direction . He made surveys on dancing pattern of honeybees over two decades and described the communication pattern of honeybees .
When bees fly out of the hive , they use the sun as a compass for navigation , that is , to remember the direction . They adjust for the sun ’ s `movement ’ through their internal clock . They are thought to use `optical flow ’ ( the number of images that pass through ) to measure the relative distance flown . When a bee finds a sugar source ( nectar ), it returns to the hive and communicates with its hive mates by performing special dancing movements . The first bee , which located the flower , carries the scent of the flower it has visited . So , the followers also seek the flower of the same scent . The distance , direction and richness of the food are also expressed by the dancing pattern of bees . When a food source is close to its hive , the bee performs a round dance . If the source is relatively distant from the hive , the dance takes the form of a figure-eight ( waggle dance ). The bees perform sickle dance when the food is in intermediate distance . When the amount of food sources is rich , the dance is longer and more vigorous . Bees gradually slowdown the dancing movements when the food is exhausted .
The foraging bee uses the sun as a compass and records the position of the food sources . So , the direction of the dancing is shifted periodically according to the direction of the sun . While returning they also perform the amuse dance by which they increase the number of foraging bees , the workers .
Why do our veins appear blue though the blood is red in colour ?
There is the myth that oxygenated blood flowing in the arteries is red in colour and the blood turns blue in colour when it loses its oxygen . Thus deoxygenated blood flowing in the veins appears blue . This has no scientific basis whatsoever . Blood flowing in the arteries as well in the veins is always red in colour .
WINSPIRE : Empowering youth | January , 2017