Of the one million identified species of insects humans share the planet with, 40% of them are under serious threat.
As small farmers, we rely on insects of all kinds to assist us with pollination, decomposition, pest control and a host of other activities.
Insects are characterised by having three pairs of legs and two pairs of wings ~ which are sometimes reduced or absent. They have three body segments: the head, thorax and abdomen. Some of them change their appearance during development in a process known as metamorphosis.
Lepidoptera (moths & butterflies), Hymenoptera (comprising the sawflies, wasps, bees, and ants) and dung beetles (Coleoptera) are the taxa most affected by extinction.
Four major aquatic taxa (Odonata, Plecoptera, Trichoptera and Ephemeroptera) have already lost a considerable proportion of species.
Affected insect groups not only include specialists that occupy particular ecological niches, but also many common and generalist species.
At the same time, the abundance of a small number of species is increasing; these are all adaptable, generalist species that are occupying the vacant niches left by the ones declining.
Reasons for decline of insects
- habitat loss and conversion to intensive agriculture and urbanisation;
- pollution, mainly that by synthetic pesticides and fertilisers;
- biological factors, including pathogens and introduced species;
- climate change.
Once again smallholders need to rethink current agricultural practices, in particular a serious reduction in pesticide usage and its substitution with more sustainable, ecologically-based practices.
In addition, effective remediation technologies should be applied to clean polluted waters in both agricultural and urban environments.
Insects also form a vital part of the food chain. Without them, there would be fewer birds, and many other animals that rely on insects as food.
Even more sobering is the fact that the world would be littered with decomposing organic material. The consequence would be complete degradation of our soils. All remaining life would subsequently disappear.