Why are insects attracted to light

We have all, at some point in our lives, been inquisitive as to what drives multitudes of insects to a source of light. We observe blankets of black bugs and moths dancing in ecstasy around the street lamps. There are many theories, all based on some scientific tenet, that try to explain this strange affinity of the insects with light, which gets accentuated in darkness.

To seek a safe refuge while there are signs of danger is the need of every organism on earth. Insects are no different. They perceive light as a safe place that wards of any imminent dangers. As to what defines these unforeseen dangers is still unexplained, but this is one of the more popular theories going around. The journey towards light is the journey towards safety for insects, and this is good enough reason for them to get attracted to light like the poles of a magnet. Whereas light is the destination for most of the insects. There are also some of them who are known to treat light as the map to their destination. For instance, an insect bound north would safely bet on the direction by treating a source of light as the indicator. However, this source must remain constant in both position and light intensity. Thus, some moths keep tracing circular trajectories around lamps and lights as they intend to keep the brightness on one side of themselves. But the counter argument that moths exhibit the same behavior even in daytime, when there is the much more reliable and prominent light source, the Sun.

Clearly, there is some scope for improvements in this navigational view of the relationship between light and insects. Another rather interesting theory states that insects display affinity not for the light, but for the darker outlines of these illuminated spheres. Yet another theory points towards the biological construction of the eyes of the insects. The multiple lenses prefer proximity to light. Visibility is a pre-requisite for insects to avoid being gobbled up by a larger creature on prowl, and this is what, in all likelihood, drives insects towards light.