But humanity has not repaid orangutans with kindness. The numbers of these distinctive, red-maned primates are now plummeting thanks to our destruction of their habitats and illegal hunting of the species. Last week, an international study revealed that its population in Borneo, the animal’s last main stronghold, now stands at between 70,000 and 100,000, less than half of what it was in 1995. “I expected to see a fairly steep decline, but I did not anticipate it would be this large,” said one of the study’s co-authors, Serge Wich of Liverpool John Moores University.

For good measure, conservationists say numbers are likely to fall by at least another 45,000 by 2050, thanks to the expansion of palm oil plantations, which are replacing their forest homes. One of Earth’s most spectacular creatures is heading towards oblivion, along with the vaquita dolphin, the Javan rhinoceros, the western lowland gorilla, the Amur leopard and many other species whose numbers are today declining dramatically. All of these are threatened with the fate that has already befallen the Tasmanian tiger, the dodo, the ivory-billed woodpecker and the baiji dolphin – victims of humanity’s urge to kill, exploit and cultivate.

As a result, scientists warn that humanity could soon be left increasingly isolated on a planet bereft of wildlife and inhabited only by ourselves plus domesticated animals and their parasites.