Rod Liddle examines our differing responses to related animal species and tries to establish what those responses tell us not merely about the animals but about ourselves.

Rod considers the otter and the mink - the one a playful, affectionate emblem of British environmental awareness, the other invariably depicted as a voracious invader.

Sir David Attenborough and ecologist Johnny Birks help Rod to separate fact from fiction and understand why one member of the Mustelid family should have us cooing and handing over money to environmental causes while the other can expect loathing at best and, more often than not, calls for a mass cull.

A keen amateur naturalist, Rod begins his debate with mink expert Johnny Birks on the banks of the River Lugg in Herefordshire. Otters and mink roam these banks side by side as uneasy neighbours. But the popular myth that mink were part of the reason for the dramatic decline in otter numbers in the 1950s was just that - a myth - albeit a convenient one.

He also hears from people involved in the Hebridean mink cull who are acting to save indigenous bird species in the Western Isles.

As the debate matures, it appears that below the biodiversity arguments lies a more fundamental clash between the pure Darwinists who believe that nature should be left unchecked and those who say it is unrealistic to abandon our position of power over the wild animals and their habitats. It follows that we must make difficult choices about which species we want to control and in some cases cull in order to protect the many. Show less