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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