Certainly! I think I’ll discuss a particularly well-known trait of moths - their tendency to gravitate towards light. Firstly, I must introduce you to the term‘phototaxis’, which refers to an organism’s automatic behaviour towards light - cockroaches, for example, are negatively phototactic, and tend to scurry for darkness. Moths, of course, are positively phototactic, though as for why…well, there’s no definitive explanation, but there are several theories.
The first theory would be that moths use a method called transverse orientationas a form of celestial navigation - in other words, to fly in a given direction, they would keep the moon at a fixed angle relative to their bodies. Under normal circumstances the moon would most likely be the brightest celestial object, but with the advent of artificial porch lights, the moths are likely to be confused. Given the great distance between us and the moon, the change in angle between the moth and the light source would be negligible - however, with a much closer artificial light, the angle would shift dramatically after only a short distance. The moth, therefore, would instinctively attempt to correct its direction by turning towards the light, resulting in a spiral flight path.
The rosy maple moth. Lovely, isn’t it?
There is one problem, however - the very simple fact that moths do not fly in a spiral. A researched named Henry Hsiao established this, actually, by tracking their flight patterns (he did this by tethering moths to tiny Styrofoam boats in an artificial pond, by the way).
Other theories have, unfortunately, been similarly discredited - such as the theory that bright lights mean safety. Moths are nocturnal, after all, and there is no natural light source as bright as a porch light at night. It can’t be moths being attracted to warmth either, for ultraviolet lamps attract more moths, despite being cooler.
Generally, however, two types of behaviour have been observed among moths - when they spot a light source from far away, up to two hundred feet, they make a beeline straight towards it. As for why…nobody knows. When they get close to the light, however, they begin to avoid it, for a bright light to a nocturnal creature should mean danger. The moth doesn’t fly directly away from the light due to a peculiarity of vision called a Mach band, which is the region surrounding a bright light that seems darker than any other part of the sky. Hsiao, therefore, conjectured that the moth’s atom-sized brain determines the darkest part of the sky is the safest. Therefore, it roughly circles the light in the Mach band region, usually at a radius of about one foot, depending on the species. It isn’t a perfect theory in the slightest, but it does help throw some light - if you’d forgive the pun - on the moths’ peculiar behaviour.