Sepúlveda 1 Bryan Sepúlveda Bahamundi Prof. Gayle Griggs INGL 3231 Section 016 3 November 2011 Extinction: Death beyond Death Millions of years ago dinosaurs ruled the earth. There were thousands ofspecies on land, in seas and even in the air. Evolution, the “modification” of species from one generation to another (Campbell et al. 452), seemed to have been working well for them. Then, why arethey not around anymore? The answer is simple: extinction. Extinction can be defined as the moment when a species has completely “died out” or when a species has not been observed for a long period oftime (Connor). It is important that humans prevent extinction because once it occurs there is no going back and it can affect anything from animals to bacteria and even humans. There are many factorsthat can cause extinction. Some are natural but others are human originated. One cause of extinction can be the introduction of “invasive species”, species that are not native to a certain region, intoa habitat (Clavero and Garcia-Berthou 110). Meteorites impacting earth can also cause extinctions. This is what many scientists believe that killed the dinosaurs and many other species, causing amass extinction; however this theory is very controversial (Veron 463). Another very important factor that can lead to extinction is the species inability to adapt to climate change. According to Natureby 2050 up to a 37% of the species they have studied will be “committed to extinction” if climate gets warmer (145). On the other hand, a very interesting form of extinction is planned extinction oreradication. This occurs when scientist plan to eradicate (eliminate) certain type of bacteria or virus to fight a disease. This was the case of smallpox which since 1980 was declared “eradicatedglobally” by the Thirty Third World Health Assembly (Dowdle 17).
Sepúlveda 2 Puerto Rico has endangered and extinct species. Perhaps one of the most noticeable animals to be endangered in Puerto Rico...
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