The loss of a single Dalmatian meant little to the pacemaker program at Montefiore. The new prototypes would be tested on another dog, and another, and many more; Furman's research yielded plenty of discoveries in the years that followed. (To name just one: In 1967, he devised a way to check the function of an implanted device automatically over the telephone.)
Not even the doctors who were performing these experiments understood just how important the new inventions would soon become. Heart disease was already America's leading cause of death in 1965, as it had been since about 1930. But few cardiologists at the time had ever seen a case of heart block—most of its victims were elderly people with modest access to medical care, and they were dying before anyone could make a diagnosis.
That all began to change with the invention of Medicare. On July 9, less than a week after Pepper's death, the Senate voted to make health insurance universal for elderly Americans. Nineteen million patients enrolled in the program the following year, and it soon became obvious how many adults were suffering from slow heartbeats in their old age. Now, for the first time, there was enough money to treat them all.
The particulars of Pepper's death scarcely mattered to the revolution in cardiology. But her final moments on the operating table do carry their own historical resonance: Medical science as we know it today—constructed on a framework of experimentation, observation, and reason—had begun in much the same way a few centuries before, with a dog laid on its back, its breast cut open, and its heart snipped in two.
What might easily be called the founding experiments of modern medicine were conducted in the first decades of the 17th century, by English physician William Harvey. His crucial discovery that blood circulates in a closed system began with a series of gory demonstrations on the bodies of living animals. For one, he would expose the beating heart of a dog, horse, or other creature and puncture its left ventricle. The geyser of blood that erupted with each contraction suggested that the motion present in the arteries and veins wasn't mere sloshing about, as had been the theory, but rather the result of a "forceful systole" of the heart.
Those skeptical of Harvey's conclusions opened the bodies of living dogs to see for themselves, and according to historian and philosopher of science Rom Harré, the dog soon became a standard instrument for the study of circulation. By the mid-1660s, Christopher Wren had devised a method for the intravenous injection of chemicals—opium and Spanish wine, to start with—into the bloodstream of a dog, and Richard Lower had performed the first successful blood transfusion by using a chain of quills to connect the artery of one dog to the jugular vein of another.
The dog remained a vital tool in biomedical research for more than 300 years and was the vehicle for a remarkable run of medical breakthroughs. Ernest Starling's research on dogs led him to declare the existence of "hormones" in 1905. In 1921, Canadians Frederick Banting and Charles Best discovered insulin as a treatment for their colony of dogs with surgery-induced diabetes. In 1923, George Whipple used a Dalmatian-English bulldog cross to create a model of pernicious anemia, then cure the disease with supplements of liver. * And shortly before Pepper's death, a stray mutt plucked from the streets in Moscow became the first animal to be launched into orbit. Though that dog died from stress and overheating only a few hours into the mission, the feasibility of human spaceflight was reported around the world.
By the 1960s, Furman and his colleagues at Montefiore Hospital were using a few hundred dogs for research every year, while larger institutions went through as many as 9,000. Rep. Joseph Resnick, the upstate lawmaker who attempted to intervene on behalf of the Lakavages on the very day that Pepper was killed, would later assert to the newspapers (and his fellow members of Congress) that the annual number of dogs used in federally funded research had reached 1.75 million.
But the dog-napping of Pepper marked the beginning of the end of canine experimentation. Outrage over her demise, and the theft and killings of other family pets, would soon turn public opinion—and federal law—against the use of dogs in biomedical research. Meanwhile, the rapid growth of American science after World War II had already created a new industry in purpose-bred, standardized lab animals—and the thriving trade in stray mutts and stolen pets would soon be replaced by an assembly line of laboratory flies, rats, and mice. Pepper's death in the summer of 1965 signaled the end of an era.
Correction, June 11, 2009: The original version described iron supplements as a cure for pernicious anemia. It was the vitamin B12 in liver that served as the basis for Whipple's cure. His experimental dogs did have an iron deficiency, however.) (Return to the corrected sentence.)