An adaptation is an evolutionary process of a living species to live in its habitat or habitats and to be capable to reproduce. As the environment is not a permanent existence, the organisms have to keep adapting to the changing environment.
Adaptation is the process by which organisms constantly adjust and change according to the changes in external habitat, so that they can survive and reproduce. Adaptation can be acquiring new survival skills, or losing unwanted skills.
Adaptation is a process which runs parallel to evolution. Today, if we see species like dinosaurs extinct, it is because they could not adapt to the changing environment. As we study evolution, we also notice the various stages man has been through before becoming the modern man. It is all a part of ecological adaptations.
We can see a number of lie examples of adaptations in our day to day life as well. Usually, whenever we go out in the hot sun for a long period of time, we get a tan. This tan is how our skin adapts to the heat and UV radiation from the sun. As the exposure to heat and UV rays increases, the melanocytes present on skin increase the production of melanin. It is a pigment that absorbs the heat and also protects the nucleus, thus protecting the DNA from mutation due to UV rays.