Sometimes it takes an outsider to really look at something, to see it with new eyes and a new understanding. Australian ecology professor Tim Flannery, in his book "The Eternal Frontier: An Ecological History of North America and its Peoples," shows us an entirely fresh, mind-blowing perspective on the natural history of this continent's geology, flora, and fauna.
North America truly is an "eternal frontier," with new waves of species (including humans, recently) flowing in from other continents across the ages of geologic time. Professor Flannery's book is a monumental work, covering the last 65 million years of extinction, repopulation, adaptation, and migration.
He begins with the asteroid that slammed into the isthmus of Mexico, creating the Chicxulub Crater and destroying the dinosaurs (presumably). North America bore the brunt of this planetary catastrophe; Flannery points out that only the forests on the coastal sides of the Sierra and Appalachian Mountains would have been spared the shock wave and firestorm from the impact. Those surviving plants and animals, along with new immigrants from neighboring continents, repopulated all of North America, evolving as they went.
This cycle has repeated with each new shock to the continent's ecosystems: Ice Ages, warming periods, the arrival of the first Americans, and the current crisis flowing from the arrival of the second wave of humans from around the world. After each ecological shock, an entirely new regime of plants and animals develops.
Along the way, Flannery shows us the significance of North America's topography; how the north-south funnel shape of the continent, bounded by mountains on the coasts, allows cold air to sweep down from Canada unimpeded, and run into hot air from the Gulf, creating severe weather systems unrivaled on all the other continents, whose mountain chains run east-west.
He also describes some of the amazing animals that have made their entrances and exits from the continental stage: mammoths, mastodons, horses, camels, and saber-toothed cats; but also giant ground sloths the size of elephants; huge, hideous carnivorous pigs; quick and deadly short-faced bears; terrifying meat-eating birds larger than ostriches; and some even weirder beasts. Ever wonder why pronghorn antelope can run so quickly, so that no wolf has a hope of catching them? They once had to flee from American cheetahs.
At 357 pages (in paperback), this book provides a sweeping overview of North America's natural history. The most fascinating sections are those in which Prof. Flannery gets down to the nitty-gritty of a specific epoch or species; the book could really be twice as long, in order to provide him room for more of his lyrical and detailed story-telling. Readers probably will be prompted to research the most interesting tidbits further. Nonetheless, "The Eternal Frontier" is a rollicking, riveting journey through geological and ecological time. I highly recommend it.