Threatened applies to those species whose population levels are declining and that are likely to become endangered in the forseeable future. If species considered endangered or threatened are not protected they may become extinct. Species become extinct when all individuals of that species die. When this occurs, the species and all the genes of that particular species' genetic line are lost forever. To prevent extinctions it is important to protect and show respect for the earth's biodiversity.
Biodiversity refers to the total number of species, genes, and ecosystems found on our planet.
It is a representation of the wealth of life on earth, a wealth which has undergone hundreds of millions of years of evolutionary history, and to which many human cultures have become adapted. Biological resources provide mankind with all of its foods, and form the basis of many medicines and industries. The enormous variety of life in the form of genes, species, and habitats has incredible value as it allows humans to successfully meet the demands of the ever-changing environment in which we live. The full potential of our biological wealth therefore remains unknown and untapped. Nonetheless, largely due to human activity, we are currently experiencing the greatest loss of diversity of species, genes and ecosystems since the mass extinctions of prehistoric times, some 65-500 million years ago.