Extinction can be defined as a phenomenon in which a given species or organism comes to an end. Scientifically, extinction occurs when a species can no longer compete for survival in changing environmental conditions. Extinction of both plants and animals imposes major threat to humanity because it is a major environmental problem on earth and hence a subject of discussion. The rate of loss of species is alarming and it has been attributed to mankind activities particularly the degradation of plant and animal habitats.
The destruction of species’ habitant may take the form of physical destruction of forests, toxicity or by introduction of new species which limits species ability to survive and compete for the available resources. Transportation of plants and animals from one geographical area to another has been done by man for long time either intentionally or by accident. This has proved to contribute extensively to extinction of species.
This is because the species can be established in the new geographical area as an alien species which can affect the original species by competing for the available resources, eating them, or by introducing other harmful species which degrade their habitat. People who exist within a given environment depend on the survival of all plant and animal species in that environment and therefore the loss of these species can be catastrophic and threat to human life. For instance, we depend on plants to clean the air we breathe, that is, take in carbon dioxide and give out oxygen, which we breathe.
Plants are also a contributing factor to formation of rainfall, the main source of the water we use. The extinction of plants and animals would actually result into ecological imbalance. It is therefore clear that human beings are undoubtedly contributing to the elevated extinction rates and that we should be concerned about the loss of species if ecological balance is to be maintained. References May, R. , & Lawton, J. (1995). Extinction Rates. New York: Oxford University Press .