A barnacle shell has a little hole where the animal sticks its feathery feet to feed with. Livingbarnacles need to stay wet. At low tide, they shut the hole in the shell with a 'door' so that they don't dry out. A shell without a door is an empty shell, and the barnacle has di...
The term "nature" may refer to living plants and animals, geological processes, weather, and physics, such as matter and energy. The term is often refers to the "natural environment" or wilderness—wild animals, rocks, forest, beaches, and in general areas that have not been substantially al...