There was no place in the world like it. There still isn't. Eighty percent of all that lives in Australia, plant and animal, exists nowhere else. More than this, it exists in an abundance that seems incompatible with the harshness of the environment. Australia is the driest, flattest, hottest of all the inhabited continents. (Only Antarctica is more hostile to life.) And yet it teems with life in numbers uncounted. For insects alone, scientists haven't the faintest idea whether the total number of species is 100,000 or more than twice that. As many as a third of those species remain entirely unknown to science. For spiders, the proportion rises to 80 percent.