Here is an analogy based on form and not on function. Trees have many leaves and birds have many feathers. They both have large surface areas, but their functions are completely different. Leaves absorb sunlight for the production of sugar and facilitate gas exchange. Feathers provide lift for flight. This is a good example of an analogy in which 2 things should not be compared. Using this to teach would only confuse the students.
Feel free to be the first
Please review the linked page for context.
If you can think of something better than this,
please add it to the database