Daily assignment

Topic: The Invasion of Alien Species

In many parts of the world, alien species are harming the environment causing many problems. Generally, alien species in term of animals are species that moved from their original area to a new place. Sometimes, they arrive accidentally or they can be introduced by human being in order to fight other species. At once they are introduced, they multiply dramatically. Over the time, sometimes decade, sometimes a few years. The invaded species take living space and food away from the native plants or animals. The result can mean drastic change in the natural landscape and problems for people.
As example, the yellow ants are an alien species introduced in Cameroon forty years ago. Today the result is terrible because of their harmfulness to people, other animals and ants. According to many investigators, they may be coming from Europe inside some used car tires. Other believed that they came from Asia inside some used shoes and clothes. At the begining, they were just a few creatures however, they grew and multiplied exponentially. Today it is a serious problem for the government that spends at leas more than one million dollar every year to fight them but unsuccessfully. Not only they attack and destroy other kinds of ants but also they harmfully bite human being. At once you are bitten by one you will feel very pain the whole day and children bitten may end up at the hospital where they will have intensive care.
At the begining they taught that killing them with toxic chemical spray will solve the problem but today not only they have become more resistant to the chemicals but also those substances are a source of contamination for people.
According to some scientists, another type of alien species is the mongoose. Those small animals were brought to Hawaii in the 1800's to kill rats in sugarcane fields. Since then, they have grown in number so that they are a major threat to bird life on the island. their favorite food is birds' eggs. Thus the mongoose has caused a lot money worth of damage to poultry farmers in Hawaii, and it has great reduced the numbers of many native bird species.
Although many people believe that alien species are beneficial for human being, their damages are more harmful than their utility.

Written by David Lateu