Today we have a guest blog by Dr George McGavin, explaining why insects are so important.
However you look at it insects are the most important group of animals on Earth. These six-legged creatures have been around for over 400 million years. They were the first animals to colonise the land and wings allowed them to complete their conquest of the planet. More than half of all known species and about three quarters of all animals are insects and there are many millions more awaiting discovery.
Insects provide what are known as ‘ecosystem services’ on a global scale. For example, most animal species rely on insects as their only source of food. Without insects to eat many groups of higher animals such as birds and bats would disappear. And millions of humans eat insects as well. All over the word about 1,500 species of insect provide an important source of protein and micro-nutrients such as iron, calcium and vitamins. Insects also pollinate the vast majority of the world's quarter of a million or so species of flowering plant, a mutually beneficial interaction that evolved 100 million years ago. By attracting insects to carry their pollen and rewarding them with food, plants were pollinated much more effectively than if their pollen simply blew around in the wind. Think of all the flowers, fruit and vegetables today that wouldn’t exist but for the work of thousands of species of bee. Despite being small with a tiny brain, bees can learn the shortest, most efficient route between multiple flowers, a complex mathematic task that would keep a modern computer busy for days.
At least a quarter of all insect species are parasites or predators of other species of insect, keeping their own numbers in check. Ants alone are the world's most numerous carnivores, eating far more animal flesh that all other meat eaters put together. Insects also recycle nutrients, enrich soils by disposing of carcasses and dung. But of course not all insects are good news. Herbivorous insects eat up to a fifth of all crops grown and locally, the losses may be much higher. In addition, insects carry the viruses, bacteria and other organisms responsible for many plant, animal and human diseases. About one in six human beings alive today is affected by an insect-borne illness of some kind. Malaria alone kills one person every 12 seconds and infects as many as 500 million people alive today.
We still have a great to learn from insects and if life has evolved past the stage of a single cell elsewhere in the universe, it is very likely it will look a lot like a bug or a beetle.