Illustration by John Sadler www.johnsadlerillustration.com 

• I HAVE heard theories that restoring species like the mammoth could help the fight against climate change by recreating grasslands in the tundra regions which would soak up more carbon and thus suppress global warming.

A bit of a long shot maybe, but the thought of the magnificent mammoths roaming the Earth again certainly warms the heart. It also brings to mind the metaphoric use we have put to the name of the species.

That is a description of vastness which would be appropriate to the scale of tax that should be levied on those companies and investors who have made a vast fortunes out of exploiting black gold regardless of its effect on the survival or our planet.

While we have to breathe polluted air (and spend hours every year sorting out our toxic rubbish also produced by “Big Oil” ready for the bin men) big companies are happily churning out more poison and raking in more profits.

Your Comment (ULEZ: little people pay while big companies get off scot free, August 31) is exactly right. Stop penalising the poor and make the rich share a bit more of their ill-gotten gains.

M BARNES, WC1