Biodiversity in an area means the multiplicity of various species, the genetic wealth of each species, and the relations between species and natural environments within which these beings evolve. This diversity, which it is possible to see and enjoy in our environment, is one of the great divine miracles.
Unfortunately, it is gradually but constantly dwindling due to human activity, and this will have dangerous consequences for the future of mankind.
Many factors contribute to the extinction of species, mainly:
The decline or suppression of the natural milieu or environment: all flora and fauna depend on the environment where they live to procure their food and water, their shelter and their living space. These environments are increasingly disappearing because of the space requirements of a growing population for agricultural and industrial purposes and for urban expansion.
Pollution: various types of pollution are contributing to the disappearance of both flora and fauna. Turtles, for example, eat floating plastic bags, mistaking them for jelly-fish. They die or suffocate, because they have difficulty swallowing their food. Similarly, birds are likely to eat toxic products which farmers spray to get rid of harmful insects.
Trade in wild animals : trade in big game threatens with extinction a number of species around the world. Although many laws have been passed to protect these endangered species, the tempting profits this trade holds out encourage traders to take the risk. For example, the rhinoceros is hunted for its horn; in eastern countries this is used to make traditional daggers and is believed to have medicinal value. The cactus and many other succulents are sold illegally, as are many species of parrot, whose marketing is against the law.
Exogenous species: when an alien species is introduced into a given area, it may have advantages which allow it to survive better than the native species. It may well thus threaten local species with extinction. In certain cases, the local species cross with the intruders, as happened with the African wild cat.
Unauthorised hunting: this practice is usually - but not always - linked to the sale of a determined species. The African wild dog, for example, has become one of the African carnivores most likely to become extinct because for a long time herders have hunted it down pitilessly.
Amazingly, we do not know how many living species there are. The number of known species is over 1.4 million, whilst the total number is thought to be between five and 30 million species! The destruction of these species' natural environments is dangerous - millions of these species will disappear without even being known.
The biodiversity existing on earth is the result of 3.6 million years of existence and evolution. Disappearance is part of the life process, in the sense that well-defined species die out because they fail to adapt to changing ambient conditions. But recently the rate of extinction has speeded up considerably. It is now between 1,000 and 10,000 times higher than the natural - that is, without man's intervention - rates.