I remember when our children were younger, and we went on our summer holidays by car, that the car windscreen would be splattered with the remains of dead insects. This summer my wife and I drove to Cornwall and back for our holidays almost without a single insect hitting our windscreen. Where have all of the insects gone? It would appear that we, the human species, have wiped them out as a consequence of the way we exploit the planet for our own comfort and convenience. Insecticides and monocultures aided by genetically-modified crops make a direct contribution but our consumption of fossil fuels and intensive production of everything from beef [see ‘A startling result‘ on May 18th, 2016] to plastics is changing the environment [see ‘Productive cheating?‘ on November 27th, 2013]. The biologist, Edward O. Wilson observed that ‘If all humankind were to disappear, the world would regenerate back to the rich state of equilibrium that existed 10,000 years ago. If insects were to vanish, the environment would collapse into chaos.’ It looks like we are on the cusp of that collapse.
Cristiana Pașca Palmer, the executive secretary of the UN Convention on Biological Diversity has highlighted the impact of our actions as a species on the other species with which we share this planet. We are making the planet uninhabitable for an increasing number of species to the extent that the rate of extinct is perhaps the fastest ever seen and we might be the first species to catalogue its own demise. Our politicians have demonstrated their inability to act together over climate change even when it leads to national disasters in many countries; so, it seems unlikely that they will agree on significant actions to arrest the loss of bio-diversity. We need to act as individuals, in whatever way we can, to reduce our ecological footprints – that impact that we have on the environment [see ‘New Year Resolution‘ on December 31st, 2014] . As the Roman poet Horace wrote: ‘You are also affected when your neighbour’s house is on fire’; so, we should not think that none of this affect us.
I am not sure whether windscreens are an appropriate testing method especially when considered over time 🙂 Did the drag coefficient not change significantly? Also, if we just increase the number windscreens on the road would that not also affect the measurement?
I’d agree with Wilson’s equilibrium thought but I am willing to speculate (!) that the biodiversity and insect mass was not much (that’s debateable) greater 10000 years ago because middle Europe was mostly covered in forests and lacked the landscaping and attractive piles of stuff that humans are voluntarily leaving all over the place. We undoubtedly have less swamps and more sealed surface though, which will have an impact on insect population. We unfortunately also lack data on what would be an “appropriate” insect population, which may be borderline philosophical 🙂 Cheers, Felix
Fortunately, much better evidence about the loss of insects is available. For instance, Hallmann et al  found a more than 75 percent decline over 27 years in total flying insect biomass.
Hallman CA, Sorg M, Jongejans E, Siepel H, Hofland N, Schwan H, Stenmans W, Muller A, Sumser H, Horren T, Goulson D, De Kroon H, (2017), More than 75 percent decline over 27 years in total flying insect biomass in protected areas, PLoS ONE 12 (10):e0185809.