What is the Line of Symmetry?
The ‘Line of Symmetry’ is an imaginary line that can be drawn down the middle of some objects so that the resulting halves match exactly.
Symmetry and the Butterfly
The blue line on the butterfly above is its line of symmetry. Notice how the patterns on the wings are an exact mirror image of the other. Also notice how the shape of the wings & other body parts are perfect reflections of the other side.
Near Symmetry in Nature
The difference between symmetry in the animal world and the symmetry of Math Class drawings needs to be noted. In math lessons the symmetry examples given are usually perfect. Every diagram has one side the EXACT mirror image of the other.
In nature, the examples of line symmetry are only very, very close to exact. They are not perfect. This ‘closeness’ is referred to as ‘near symmetry’ or ‘approximate symmetry’.