Physicists use three basic principles in optics:
A surface warms up more as the light rays striking it approach 90 degrees.
If two surfaces receive light at the same angle, the darker one will warm up more.
When light strikes a reflective surface, it's reflected at the same angle as it arrived.
Although students of physics know these laws, many people today are unaware of their effects on daily life and the purposes they serve. What is surprising, however, is that there are other creatures that put these principles to good use.
In their daily lives, butterflies make use of these laws, of which many humans are ignorant. For example, the Colias butterfly is unable to fly when its body temperature drops below 28oC (83oF). In that event, it immediately spreads out its wings and, turning its back to the Sun, adjusts them perpendicular to its rays. When its internal temperature rises to a sufficient40oC (104oF), its turns around 90 degrees, which minimizes the warming effect of the Sun's rays, and the butterfly's body temperature starts to fall.
On its wings, this species of butterfly has black spots that also serve to collect heat in the butterfly's body. Significantly, these spots are located near those regions of the body which most need to be warmed, so that the heat is transferred over a shorter distance.
On the other hand, the Pieris species of butterfly arranges its wings at such an angle that, just like with a reflector, it can concentrate all the heat rays onto those regions most in need of warmth. ("Gunes Kolektoru Gibi Kelebek" (The Solar Collector Butterfly), Bilim ve Teknik, April 1991, p. 49.)
These butterflies have certainly received no training in physics or optics. They are unaware of the laws of physics and of the angle at which solar rays can be most productive.
It is God, the protector and observer of all, Who inspires these creatures with what they need to do to warm themselves in the most productive manner. It is revealed in a verse that Our Lord has dominion over all:
Everything in the heavens and everything in the Earth belongs to Him. God is the Rich Beyond Need, the Praiseworthy. (Surat al-Hajj: 64)
