Whilst windscreens are one of the most important parts of your car, they have increasingly become unexpectedly important when studying the proliferation of insects, or lack thereof.

Although they have never been the biggest cause of windscreen replacements compared to gravel or hail, insects hitting the glass can create a build-up of acidic residue that can cause damage over time. 

They could also cause visibility issues, which may have legal and safety implications.

However, for people studying insects, studying bugs hitting cars has led to the discovery of a rather unsettling hypothesis known as the “windscreen phenomenon”.

Many drivers, particularly those who have had their license for a long time, have noticed that they have had to clear their windscreen of insects far less often than they used to.

Whilst this was initially believed to be the result of increasingly aerodynamic cars that are less likely to hit insects, multiple studies which included classic cars found that the number of insects that a windscreen hits has decreased dramatically, with one study claiming a drop of over 80 per cent in just 20 years.

The potential reasons for this are broad but not completely understood, and involve many factors such as insecticides, climate change and the rise of industrial farming methods that have killed off many pollinating insects.

At the same time, however, it may not necessarily reveal that the number of insects has reduced, but that they have constructed habitats further away from roads and houses.

Part of the issue is that historic insect population data is extremely poorly kept and largely anecdotal, which has made it difficult to understand why insect populations have fallen so much and so many windscreens are rather concerningly clean.

The windscreen phenomenon is not necessarily revealing new information but instead shows a way in which our personal driving experiences can potentially reveal broader facts about the world.