Extinction Rates of Species
Biological scientists define extinction as the end of a group oftaxa due to the death of the last individual of that particular species or organism.
Extinction has largely been witnessed in variety of species and this can attributed to both environmental factors and human factors. Scientists say that the largest threat in the extinction of species is contributed by man’s destruction of the habitat whereby the home of a species or the ecosystem is destroyed and this has been witnessed mainly in the waters when we put chemicals inside. It has been seen that 17 out of every 22 crocodiles become extinct due to this type of habitat destruction. (Grinning Planet 2004)
Excessive hunting has also triggered most recent extinction rates of animals such as the rhinoceros which are being hunted for the horns, others include lions and tigers. We have also seen that due to the destruction of the environment by man has caused climate change and global warming contributing to extinction of species as suggested by botany specialist Peter Raven who says that 25% of different plant species in the world become extinct due to pollution and climate change (Grinning Planet 2004). Other causes are predating, natural selection/competition and disease.
These areas should be of major concern to us in order to look for the control and conservative measures of co-extinction where we witness extinction of parasites due to extinction of hosts or issue of predators and preys. We should also take into our concern on the processes of speciation i.e. arising of new varieties of organisms through evolution and also the Lazarus taxa where species assumed extinct reappears abruptly. (Wikimedia Foundation Inc 2010).
Grinning Planet. (2004). Endangered species/species extinction – Causes, statistics and trends.
Wikimedia Foundation Inc – Wikipedia (September 2010). Extinction