Dearbhail McDonald (We need to talk about the children we’re not having, 8 March) makes some interesting points but seems to miss the essential nature of the problem, which is over, not under, population.

Our species took some 200,000 years to reach its first billion individuals in the mid-1900s, then doubled that number in 70 years. By the 1960s, by which time the figure had risen to over 3 billion, a number of wise voices were raised but effectively ignored. Now we are approaching 8 billion and overall the numbers are still rising even though just about every existential threat our planet faces is either directly caused or exacerbated by our ever-swelling numbers.

Countries where a decline has set in should be adapting and celebrating what, if managed sensibly, could be the best environmental news in a century. Yes, there will be demographic problems initially. But these can be tackled with a move to a new economic paradigm that our planet needs to survive. Growth economics must be consigned to the dustbin of history and new technology, together with new status and rewards for carers, employed to ameliorate the problems of old age. To do this there needs to be a massive redistribution of wealth and selfish vainglorious politicians must stop trying to coax and con people into having more children.

Will this work? Well, it should have started at least half a century ago. But it is the only hope now for our planet and therefore for all of us, because we don’t have a spare one available.

Steve Edwards

Wivelsfield Green, East Sussex

• Yet another article fretting that a falling birth rate “is one of the biggest humanitarian crises of our time”. Sure, in the UK, our pension system, housing and immigration policy need to be overhauled. But please will people face the major problems of the future. There are now more people alive than ever before. Already climate change, species extinction, pollution of seas and air, soil degradation, antibiotic resistance and sea level rise are all having an impact. These factors are global problems that can lead to famine, disease, resource wars and mass migration of climate refugees – a real humanitarian crisis. Recycling and reducing individual consumption will have little effect if there are many more of us, all hoping to live to a reasonable standard.

Davina Malcolm

Kimpton Bottom, Hertfordshire

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