Could man survive without insects? © Getty Images

Could we survive without insects?

It's estimated that there are 10,000,000,000,000,000,000 insects on Earth (or 200 million for every one of us) – but would it affect us if they all disappeared?

Asked by: Richard O’Neill, Glasgow

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It would be very difficult. Insects pollinate at least a third of the total volume of crops cultivated worldwide, and many are useful predators of non-insect pests such as mites. Even if we managed to convert agriculture to purely wind-pollinated crops we would have to deal with an even more fundamental problem: the complete collapse of most ecosystems.

The total biomass of insects vastly outstrips the mass of all vertebrates so insects are a vital part of most food webs. Without insects for them to eat, we would lose most reptiles and amphibians and about half of all the bird species.

Insects are also a very important part of the decomposition process that returns nutrients from dead plants and animals to the soil. The environmental catastrophe that resulted would probably totally disrupt agriculture for decades or more and leave us almost entirely dependent on the sea for food.


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