Most of us spend more time swatting away or avoiding wasps and moths than we do contemplating their importance to the web of life. But it is no exaggeration to say that the horrifying decline in the number of these creatures – the most widespread on Earth – is a barometer for the whole planet.

The new global scientific review into the perilous condition of our insects reports that more than 40% of insect species are threatened with extinction while the mass of insects is declining by 2.5% a year. This catastrophic decline is a direct cause of the existential threat to other animals, insects being at the bottom of the chain and the primary food source. Since 1970, 60% of mammals, birds, fish and reptiles have been wiped out.

The review identifies a key driver towards this mass extinction: habitat loss and conversion to intensive agriculture with its associated use of pesticides. Given this is a manmade disaster, surely we are capable of tackling and reversing it?

As a member of the European parliament’s agriculture committee, I regularly debate the use of pesticides in farming with my colleagues. I have lost count of the number of times I have begun meetings with what feels like a sermon on the Armageddon taking place in our countryside. I am always greeted with patient, patronising smiles from many of my fellow MEPs, before they go on to ignore the warnings and refuse to limit the use of pesticides in our fields.

Some of the members of this committee are themselves farmers who have grown increasingly dependent on powerful and toxic pesticides. But others have taken the agribusiness shilling and believe that their role in policymaking is simply to support the corporations that sell these poisons.

And this is the nub of the issue. What might accurately be dubbed insectageddon is being driven by the agrichemicals industry. This situation is compounded by compliant politicians and policymakers who fall prey to lobbying pressure and then refuse to implement science-driven policy to protect wildlife. This has meant that over the past five decades conventional farmers have forgotten the natural systems they once relied on to control pests. Non-organic agricultural systems are highly dependent on chemicals, so feeding a vicious circle.

‘EU member states have been slow to implement policies that reduce pesticide use.’ Photograph: Peter Barritt/Alamy

But there is a legal route out of this – in Europe at least. Since 2009 the EU has adopted the sustainable use of pesticides directive. This aims to reduce the risks and impacts of pesticide use on human health and the environment, while prioritising the use of alternative approaches or techniques such as non-chemical methods.

However, because it is a directive rather than regulation it requires implementation in national law, and the vicious circle that has led to high levels of chemical dependency also operates at national level, meaning that member states have been slow to implement policies that reduce pesticide use.

And the agrichemical industry is literally writing pesticide assessments that are then presented as the work of regulators. For example, a recent report exposed how EU regulators based a decision to relicense controversial glyphosate on an assessment plagiarised from industry reports. Around 50% of some chapters were actually a copy-and-paste job from papers Monsanto and other agrichemical corporates had written.

Scientific knowledge has given us the ability to choose that only the creatures that we value can survive on our land. But only the science of ecology has the wisdom to look at the system as a whole and to realise that killing any aspect of it will undermine other interlinked species. So to ensure that some key crops such as wheat are not troubled by insect predators, we are wiping out the very insects that crops such as oilseed rape need to be pollinated and to produce their flowers and oil-rich fruits. Tearing apart the web of life damages us all. Only a farming system that views itself as part of this web has a long-term future, and only organic farming does that.

Since I was a teenager, the Earth has lost half of all its wildlife. To avoid today’s teenagers being left with no wildlife at all by the time they are my age, we need to act fast. Changing the ways in which we produce our food is a key plank to preserving biodiversity and rebelling against mass extinction. We need to reduce pesticide use in farming, banning the most toxic ones immediately. We must use integrated pest management and dedicate more of our farmland to organic production. We also need independent scrutiny around the authorisation procedure for chemicals and so end the grip that corporate lobbying currently holds over our politicians, policymakers and farmers.

Insects are essential for the proper functioning of all ecosystems, as food for other creatures, pollinators and recyclers of nutrients. Unless we take drastic action, insects as a whole will go down the path of extinction within a few decades. And we can be quite sure that we would follow on closely behind.

• Molly Scott Cato is Green MEP for the South West of England