Over the last half a billion years, there have been five mass extinctions of life on Earth. Scientists around the world are currently monitoring the sixth, predicted to be the most devastating extinction event since the asteroid impact that wiped out the dinosaurs. Elizabeth Kolbert combines brilliant field reporting, the history of ideas and the work of geologists, botanists and marine biologists to tell the gripping stories of a dozen species – including the Panamanian golden frog and the Sumatran rhino – some already gone, others at the point of vanishing.
An example is the great auk -the original “penguin” which once thrived in great flocks in Iceland and Newfoundland. Flightless birds, like the dodo, they provided meat and feathers. An English sailor said “You do not give yourself the trouble of killing them but lay hold of one and pluck the best… You then turn the poor penguin adrift, with his skin half naked and torn off, to perish at his leisure.” They became extinct in 1844, victims of Icelandic hunters.
Extinction is a relatively new concept. In the 1790s French naturalist Georges Cuvier compared living animals to fossils and found that 23 species had once but no longer existed . In the 1970s Luis Alvarez presented the theory an asteroid had killed the dinosaurs – “The worst day ever on planet Earth” also ‘gave us our evolutionary chance’. “The reason this book is being written by a hairy biped, rather than a scaly one, has more to do with dinosaurian misfortune than with any particular mammalian virtue.”
Kolbert’s book is full of humour and she visits the Great Barrier Reef, the Peruvian jungle, and more, but her most urgent warning is about the condition of the oceans. A third of reef corals, freshwater molluscs, sharks & rays, a fifth of all reptiles, a quarter of mammals and a sixth of birds may become extinct this century. Carbon dioxide absorbed by the sea has increased by 30 per cent since the Industrial Revolution. This prevents ‘structures’ forming , with disastrous effects for the marine food chain. Increasingly ‘acid’ oceans mean that all coral reefs – which support up to nine million other species – will have dissolved within 50 years.
Kolbert concludes with a quote from the ecologist Paul Ehrlich: “In pushing other species to extinction, humanity is busy sawing off the limb on which it perches.”