IntroductionEvolution is the progressive and continuous change of characteristics within a population or species over several generations. It is the moderation of traits that can change an entire population over a long period of time and it is the theory that explains the variation in each generation of an organism. Charles Darwin's theory was natural selection, survival of the fittest and the struggle for existence. , which had a great impact on selective breeding. Organisms that were well adapted to their environment were more likely to survive and reproduce, providing their genetic traits for future generations, while organisms that were less adapted were more likely to see their numbers decline. Charles Darwin's theory also established that all species of life were related and descended over time from common ancestors. Jean-Baptiste Lamarck's theory of evolution suggested that organisms continued to become more complex through the inheritance of acquired characteristics, the idea that an organism can pass on characteristic changes acquired throughout its life on their offspring. Lamarck believed that organisms could modify their behavior to adapt to changes in the environment and that future generations would inherit these improved modifications.Pleistocene - Woolly mammoth (Mammuthus primigenius)The woolly mammoth closely resembles many modern-day elephants and is believed to be very closely related to the African elephant. They lived during the Ice Age in grasslands and tundra-like terrains that provided food for their strictly herbivorous diet of grasses, shrubs, saplings, and flower buds. An adult male mammoth could reach 3 meters high at the shoulder, it was a very useful anti-preda...... middle of paper ......live. Having thick, waterproof hair, small ears and dense trunks to keep warm, the woolly mammoth evolved into today's African elephant which has very little hair, large ears and long trunks that help it stay cool. Due to these characteristic changes, today's elephants have more predators, which is why they have learned to travel in groups, minimizing the risk of being attacked. The theory best suited to describe the evolution of the woolly mammoth is natural selection, the Darwinian theory of evolution. Natural selection played an important role in the development of the woolly mammoth, because as the environment became warmer, survival of the fittest took place. The strongest and best-adapted mammoths were most likely to withstand climate change, while the less adapted woolly mammoths struggled to survive...