Answer: Variations are the differences in individuals or their traits present within the organisms of a species which are caused by environmental and inherited factors. The inherited variation is caused due to genetic factors or information carried from the parents. Variation caused due to environmental factors includes climate, lifestyle, diet, culture etc.
Darwin explained the differences in traits on the basis of natural selection. Darwin also believed that variations in traits resulted due to inheritance and environmental factors. Darwin’s theory of evolution through natural selection suggests that individuals vary in their ability for survival as well as for their reproduction. The individuals with most favorable traits survive longer and have more number of offspring.
