Excerpt from The Zookeeper's Wife by Diane Ackerman, plus links to reviews, author biography & more

Lutz Heck soon began ministering to a handful of European bison, including those he stole from the Warsaw Zoo, hoping that they might prosper in Bial/owiezÿa’s spirit-house of trees, just as their ancestors had. Heck envisioned forest bison once again galloping along the trails, as sunlight speared through branches of hundred-foot oaks, in a woodland throbbing with wolves, lynx, wild boar, and other game, soon to be joined, he hoped, by herds of ancient horses.

Heck also sought a legendary bull, the aurochs, once the largest land animal in Europe, known for its savagery and vigor. When Ice Age glaciers melted, about twelve thousand years ago, most giant mammals vanished, but in the cold forests of northern Europe, some aurochsen survived, and all modern cattle have descended from those few—not that aurochsen would have been easy to domesticate eight thousand years ago. Because the aurochs went extinct in the 1600s, recent in evolutionary terms, Heck felt sure he could reconstruct it, and in so doing save it, too, from "racial degeneration." He dreamt that, alongside the swastika, the bull might become synonymous with Nazism. Some drawings of the era showed the aurochs and a swastika joined in an emblem of ideological suavity combined with ferocious strength.

Many ancient cultures worshipped the aurochs bull, especially in Egypt, Cyprus, Sardinia, and Crete (whose transspecies ruler supposedly descended from a sacred bull). Zeus often assumed the shape of a bull in Greek myth, the better to ravage alluring mortals and produce offspring with magical gifts; when he abducted Europa, it was in the guise of an aurochs, a great black bull with short beard and giant forwardpointing horns (like those on long-horned cattle, or on the helmets of heroes in the Nibelungen). What better totemic animal for the Third Reich? Heck’s passion for the project was shared by top Nazi officials, making it clear that Heck’s work was not just about the re-creation of extinct species. After Hitler came to power, the biological aims of the Nazi movement spawned many projects to establish racial purity, which justified acts of sterilization, euthanasia, and mass murder. One of the Third Reich’s key scientists, Heck’s colleague and good friend Eugene Fischer, founded the "Institute of Anthropology, Genetics, and Eugenics," which favored Josef Mengele and other equally sadistic SS doctors who used concentration camp inmates as guinea pigs.

Fascinated by violence and the red-blooded manly spirit—naturally brave, daring, fierce, hardy, sane, lusty, strong-willed—Eugene Fischer believed that mutations in human beings were as destructive as those in domestic animals, and that interbreeding was wilting the human race in the same way that it had already denatured certain "beautiful, good, and heroic" wild animals, losing the potent original in the genetic clutter. The roots of Nazism fed on a lively occultism that spawned the Thule Society, the Germanenorden, the Völkisch movement, Pan-Germanism, and other nationalist cults that believed in a race of Aryan god-men and the urgency of exterminating all inferiors. They exalted superhuman ancestors, whose ancient gnostic rule had brought the Aryans wisdom, power, and prosperity in a prehistoric age until it was supplanted by an alien and hostile culture (namely, Jews, Catholics, and Freemasons); these ancestors were supposed to have encoded their salvation-bringing knowledge in cryptic forms (e.g., runes, myths, traditions), which could be deciphered ultimately only by their spiritual heirs.

This ideal of racial purity really bloomed with Konrad Lorenz, a Nobel scientist highly respected in Nazi circles, who shared Oswald Spengler’s belief popularized in The Decline of the West (1920) that cultures inevitably decay—but not Spengler’s pessimism. Instead he turned to the domestication of animals as an example of how cultures decline, through haphazard breeding of robust and humdrum stock, and championed a biological solution: racial hygienics, a "deliberate, scientifically founded race policy" in which ruin is prevented by the elimination of "degenerate" types. Lorenz used the terms species, race, and Volk interchangeably and warned that "the healthy volkish body often does not ‘notice ’ how it is being pervaded by elements of decay." Describing that decay as the cancer of a physically ugly people and arguing that each animal’s goal is the survival of its species, he invoked an ethical commandment he claimed the Bible supported—"Thou shalt love the future of your Volk above all else"—and called for dividing people between those of "full value" and those of "inferior value" (which included whole races and anyone born with mental or physical disabilities), purging the feeble, both in humans and animals.

Reprinted from The Zookeeper's Wife by Diane Ackerman. Copyright (c) 2007 by Diane Ackerman. With permission of the publisher, W.W. Norton & Company, Inc.