At first sight it seems an unlikely topic for a landmark publishing deal: a fee of about half a million dollars for a book about dead animals - or, to be more precise, extinct animals.

Nevertheless the subject of eradicated species has become publishing hot property after a bidding battle in the U.S. saw Henry Holt, a publisher, beat its rivals to buy The Sixth Extinction by Elizabeth Kolbert last week. According to the New York Times, a "mid-six-figure advance" has now been agreed between writer and publisher.

"The idea of mass extinctions as the next step after talking about the perils of global warming is the most crucial subject," said Gillian Blake of Holt, after completing the deal with Kolbert, a writer for the New Yorker on environmental issues. Her last book, Field Notes from a Catastrophe, outlined evidence collated from sites across the planet showing how global warming is changing the world. The book was well reviewed on both sides of the Atlantic, with the Observer praising it as "a superbly crafted, diligently compressed vision of a world spiraling towards destruction".

Now, Kolbert is to focus on humanity's impact on the animal world, and in particular will look at the species that are today being rendered extinct by men and women. Scientists say the number of species being lost is approaching levels reached during five pivotal extinction events that have swept the planet over the past 600 million years. Among these catastrophes was the event that wiped out the dinosaurs 65 million years ago. Kolbert's task will to be show whether or not humanity -  with its spiraling population, widespread habitat destruction, over-fishing and global warming - is rivaling these.