Internal users will require a CAL which is about $100 per user. A forecast of the number of users will be used for Capacity planning for your SharePoint farm. Each server will require a server license. So the number of users may increase the cost of the server licensing.
Another example of convergent evolution is the overall body structure of the shark and the dolphin. A shark is a fish and a dolphin is a mammal. However, their body shape and how they move through the ocean is very similar.
evolution. the process of development in which an organ or organism becomes more and more complex by the differentiation of its parts; a continuous and progressive change according to certain laws and by means of resident forces. convergent evolution. the development, in animals that are only distantly related, of similar structures or functions in adaptation to similar environment. divergent evolution. the development of different characteristics in animals that were closely related in response to being placed in different environments.