Odour secretion by animals

Odour can be of vital importance in the animal kingdom. Many species use scent to transfer certain messages, such as 'this is my territory' or ' danger coming'. Here we will provide you with an explanation of how and why animals use odours. We will take ants and mosquitoes as an example.

Ants

Deborah Gordon of Stanford University has published her research of ant habits in Nature magazine. With the help of gaseous chromatography, the researchers demonstrated that each ant carries twenty-five different carbohydrates. During further research Mrs Gordon and her colleague Michael Green have been taking a closer look at which substances ants secrete and what purposes these substances have.

They have found that guardian ants secrete a certain odour when they arrive back at the colony. This odour stimulates the other ants to get to work. The ants will not start working before they have detected this particular odour, because it signals that the coast is clear and everything is safe. Only guardian ants have the ability to secrete this particular odour.

The conclusion that can be drawn from this ant research is that the right scent with in right dose guarantees order within the colony. The conclusion of this research can aid the explanation of other complex systems in neurology, computer science and artificial intelligence.

Mosquito's

How is it possible that mosquitoes always know exactly where you are, even when all the lights are out? This has everything to do with odour. Mosquitoes can detect humans by the odour of their sweat. Human sweat consists of a mixture of fatty acids, ammonia and lactic acid. Mosquitoes pick up our scent with two antennas that are located on their head. With these antennas they can also detect heat and moist. Mosquitoes can smell humans from a distance of as far as a hundred metres. A mosquito does not use its perception of heat until it is about ten centimetres away from a human being. The mosquito can also smell carbon dioxide that we breathe out. For this they use parts of their mouth.

Only female mosquitoes sting humans to feed with their blood. Male mosquitoes feed themselves with nectar.

To prevent mosquito stings you could take a number of precautions:

In your house you can place gauze in front of the windows. You can also place a special see-through curtain over your bed.

When you go outside, make sure you wear airy, well-closed clothes. To chase away mosquitoes you can use incense containing natural insecticides, such as pyrethrum. You can also rub yourself in with a mosquito-resisting substance, such as lemon juice. The best substances to be used for this purpose a natural product called Mosi Guard. This substance is based on citronella and eucalyptus oil.

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