Why do butterflies fly silently and quickly?

The movement of butterfly wings leads to the change of the surrounding air system, producing weak airflow, which in turn will cause corresponding changes in the surrounding air or other systems, thus causing a chain reaction, which will eventually lead to great changes in other systems. Linearity refers to the proportion and linear relationship between quantity and quantity, which represents regular smooth motion in space and time; Non-linearity refers to the non-proportional and non-linear relationship, which is characterized by irregular movement and mutation. For example, the eyesight of two eyes is several times that of one eye. It's easy to think it's twice, but it's actually 6- 10! This is nonlinearity: 1+ 1 is not equal to 2. The generation of laser is nonlinear! When the applied voltage is small, the laser is like an ordinary electric lamp, and the light scatters in all directions; When the applied voltage reaches a certain value, a new phenomenon will suddenly appear: the excited atoms seem to hear the command of "align to the right" and emit monochromatic light in the same phase and direction, that is, laser. The nonlinear characteristic is that it crosses all professions and permeates all fields, so it can be said that it is almost everywhere. For example, the motion of celestial bodies is chaotic; The oscillation of electricity, light and sound waves will suddenly fall into chaos; During these four million years, the direction of the geomagnetic field suddenly changed 16 times, which is also due to chaos. Even human beings are inherently nonlinear: contrary to traditional ideas, the EEG and heartbeat of healthy people are not regular, but chaotic, and chaos is the expression of vitality. Chaotic systems respond faster to external stimuli than non-chaotic systems. Therefore, nonlinearity is around us and we can't hide it.