About 66 million years ago something killed off almost all the dinosaurs on planet Earth. 70% of all species living on Earth became extinct. Extinction, the process when a species ceases to exist, is the reason why we no longer can live with some distinct, yet marvelous creatures. Although some species have been able to adapt to their environment (survival of the fittest), others have become extinct due to natural disasters, pollution, and hunting. Natural disasters such as asteroid impacts that had changed the Earth by making the dinosaurs and many other species go extinct.Global warming has also caused animals like penguins in the Antarctic that live in the cold are now warmed with everything and their food, making it harder to survive leading to extinction. Another disaster that can lead to human extinction is super volcanoes. 66 million years ago, the eruptions may have caused climate changes so sudden that many creatures were unable to adapt, causing them to go extinct from the impact. Pollution has caused the frog’s thin skin to absorb harmful chemicals, making them vulnerable to even small levels of environmental pollution.Fertilizers and acid rain have endangered frog species in specific areas. Water pollution and mining runoffs have become a threat to otters since they are extremely sensitive to pollution and can go extinct of how endangered they are. Finally air pollution has affected the Bumblebee bat in Thailand from cement plants in the latter nations that can reduce the population of bats in the area. Hunting has been around for as long man has been to survive, but what people don’t know is how it endangers many species.As well known the dodo bird, it has been hunted to extinction by humans in only 100 years of its tragic discovery and extinction. The great auk has also been hunted by death because the price of their eggs became so valuable that even museums of the time had sanctioned them to be collected, so that their skins could be used for display. Another well-known extinct mammal is the Quagga, the looks of a zebra that cross bred a horse. They have been wiped out by poachers and hunters because of their beautiful skin and hides. In conclusion, extinction is the unfortunate phase an endangered species goes through when they cease to exist.The survival of the fittest is how a species can adapt and change by natural selection with the best suited mutations and hybrids becoming suited for the environment so they can survive. The limiting factors like natural disasters, pollution, and hunting that can shift in the species’ lives, but a clever man named Charles Darwin once said, “It is not the strongest or the most intelligent who will survive, but those who can best manage change. ” According to research, the endangered species program help animals from becoming extinct and try to live with their adaptations.