American society has a confused, contradictory relationship with animals. Many dog owners have no compunction about eating feedlot-raised pigs, animals whose intelligence, sociality, and sentience compare favorably with their shih tzus and beagles. Some cat lovers let their outdoor felines contribute to mass bird murder. A pescatarian might claim that a cod is less capable of suffering than a chicken. Why do some species reside comfortably within our circles of concern, while others squat shivering beyond the firelight, waiting for us to welcome them in?

In Our Kindred Creatures, their meticulously researched history of the dawn of the animal-rights movement, Bill Wasik and Monica Murphy argue that America’s animal attitudes were largely shaped over a period spanning the mid-1860s to the mid-1890s. It was during those decades, Wasik and Murphy write, that many Americans came to realize that animals weren’t mere “objects” but “creatures whose joys and sufferings had to be taken into consideration.”

This moral awakening, described by one contemporaneous journalist as a “new type of goodness,” still influences Americans’ love of certain animals today, and our indifference toward many others. These disparate feelings, Wasik and Murphy suggest, are an inheritance from that late-1800s era. They are also influenced by spatial and psychic proximity: Most people are more likely to care about the well-being of a pet with whom they cohabit than a pig that resides in a slaughterhouse. The future of animal welfare in the United States may depend on whether Americans can expand their concern beyond the boundaries drawn by 19th-century reformers—whether, as Wasik and Murphy put it, we can apply our “reservoirs of pet love” to other, more distant creatures.

Read: The meat paradox

Wasik and Murphy’s book often makes for disturbing reading, so unflinchingly does it document humankind’s capacity for cruelty. In the 19th century, horses, ubiquitous beasts of burden in the pre-automotive age, were whipped mercilessly and forced to haul impossibly heavy loads. Medical-school instructors vivisected rabbits in anatomy lessons. High-society women sported fanciful hats adorned with the plumes of egrets, terns, and other birds “slaughtered wholesale for the cause of fashion”; offshore bobbed ships full of live sea turtles flipped on their shell, slowly dying as they waited to become soup. Every day in New York City, stray dogs were rounded up and “killed by drowning in a giant metal box … used to dispatch some sixty to eighty dogs at a time.”

Although Wasik and Murphy make the case that women eventually became central to the animal-rights movement, their account focuses principally on two men who were among its most forceful leaders. One is Henry Bergh, the dyspeptic heir to a shipbuilding fortune who embraced animal welfare after watching a bullfighting exhibition in Spain. Bergh’s approach was a punitive one: Beginning in the 1860s, he cajoled New York’s legislators into passing welfare laws, then, under the auspices of a new organization called the American Society for the Prevention of Cruelty to Animals, delegated agents to enforce those laws in cooperation with local police. His counterpart was George Angell, the president of the Massachusetts SPCA and the son of a Baptist preacher, who founded a newsletter called Our Dumb Animals and packed its pages with treacly poetry and stories written from the perspective of horses. Angell was a skilled rhetorician and salesman: When a compassionate “autobiography of a horse” called Black Beauty was published in the United Kingdom, Angell reprinted it in the U.S. (ignoring its original publisher’s copyright) and marketed it so ardently that one reporter speculated it would outsell the Bible.

Through legal and moral suasion, Bergh, Angell, and their conspirators made rapid progress. They passed laws preventing horse abuse, broke up dog-fighting rings, and nudged the meat industry to adopt less crowded train cars for cattle. In Philadelphia, a reformer named Caroline White opened a humane dog shelter at which strays were “fed a healthy diet of horsemeat, cornmeal, and crisped pork skin.” Those who weren’t adopted were euthanized in a carbon-dioxide chamber, which was thought to be less painful than drowning. Some species, then as now, were easier to promote than others: Bergh’s prosecution of a ship captain for mistreating sea turtles failed when a judge absurdly ruled that turtles were fish, and thus not subject to new welfare laws. Such setbacks notwithstanding, near the end of the 19th century, 39 of the country’s 44 states had adopted laws proscribing animal cruelty.

Although Wasik and Murphy share their subjects’ sympathies, they are admirably clear-eyed about their deficiencies, including some lamentable anti-science sentiments. Wasik and Murphy’s previous book, Rabid, tackled the history of rabies, and Our Kindred Creatures, too, spends time on that dread disease. Rabies, a common and deadly scourge in the 19th century, posed a contradiction to animal advocates. On the one hand, the development of a human rabies vaccine in 1885 was good for dogs: Once pooches were no longer terrifying disease vectors, people could welcome them into their home without reservation. On the other hand, the vaccine’s creation entailed copious animal experimentation, including “cerebral inoculation,” whereby researchers drilled holes in anesthetized animals’ skulls to infect them. Bergh and his allies deemed the rabies vaccine a “hideous monstrosity” and campaigned against its “evils,” seeming to recognize only the cruelties associated with the vaccine, and not its ultimate benefits.

Early welfarists had another blind spot: agriculture. Although Bergh and his allies occasionally waded into livestock advocacy, they railed primarily against abuses they could see: the horse whipped by his rider, the dog kicked by her owner. To Bergh’s mind, such public displays inculcated a culture of cruelism—the notion, as Wasik and Murphy put it, that witnessing meanness had a “coarsening influence on human minds … priming them for further acceptance of cruelty against man and beast alike.”

But a worldview focused on the prevention of visible cruelty proved a poor match for the meat industry. The slaughterhouses and packing plants that sprang up in Chicago in the late 1800s, for instance, concealed the brutality of their slaying methods—cows battered in the head, the occasional still-living pig dunked in boiling water—behind closed factory doors. Humane groups mostly ignored meatpacking’s horrors. The Illinois Humane Society even appointed the meat magnate Philip Armour to its board of directors and wrote him a praiseful obituary that, as Wasik and Murphy write, washed “away the blood of the countless millions of animals so cruelly disassembled in his slaughter factories.”

That cognitive dissonance—“the selective care for certain species and not others”—still afflicts American society. In their afterword, Wasik and Murphy argue that modern Americans, like their 19th-century forebears, need to adopt their own new “goodness,” one that emphasizes a “systems-driven moral thinking.” The misery of sows held captive in feedlots, or the suffering of wild creatures evicted by habitat loss, must become as real and urgent as the pain of chained dogs and starved cats. Meat-loving Americans would do well, Wasik and Murphy write, to reconsider the “patterns of consumption” that have led to the confinement of about 99 million cows and 74 million pigs. They might use their concern for pets as “well-springs from which to love, and to aid, all those distant, unseen animals we know only as abstractions.”

It’s a welcome proposal. Aside from that brief afterword, though, Wasik and Murphy’s book is almost entirely a study of the past. Our Kindred Creatures would have benefited from a more thorough examination of how early animal-welfare campaigns still reverberate—or don’t—today. Does P. T. Barnum’s deplorable treatment of captive beluga whales in the 19th century inform the campaign to free orcas and other cetaceans housed in modern aquariums? How have Indigenous-led efforts to restore bison to North America’s prairies managed to grow from the poisoned soil of 19th-century buffalo massacres? Lingering in the present would have made for a different—and longer—book, but also, perhaps, a more resonant one.

Read: How P. T. Barnum helped the early days of animal rights

Our Kindred Creatures also could have spent more time on the evolution of wildlife conservation. At the animal-welfare movement’s outset, some of the same people and groups who inveighed against horse beatings and dog drownings also fought the annihilation of bison and birds. But those causes soon diverged, as scientists and upper-crust sportsmen came to dominate conservation and largely squeezed out the lay crusaders who had launched welfarism. Today, many animal-welfare groups focus on pets and livestock, while organizations such as the National Wildlife Federation and the World Wildlife Fund advocate for their free-roaming brethren. Some scientists seek to reunify conservation and animal rights via the wild-animal-welfare movement, which works to both protect creatures and make their daily lives more pleasant—for example, by studying the effects of light pollution on owls, and by sponsoring research that provides birth control to overpopulated and starving pigeons in urban areas. After more than a century of divergence, animal welfarism and conservation may once more align, potentially to the benefit of the wild creatures whose lives have been immiserated by human activity.

Ultimately, in spite of its accomplishments, the crusade launched by Bergh, Angell, and their peers remains unfinished. As Wasik and Murphy point out, early welfarists were fond of analogies as a rhetorical tool. Some activists even extended the logic of animal rights to protect children from domestic abuse; in one instance the authors write about, Bergh dispatched ASPCA agents to rescue a mistreated child and prosecuted one of the first child-welfare cases on her behalf. If the modern animal-rights movement is to continue racking up victories, more Americans should perhaps think in analogy. If dogs and cats deserve good lives, why not cows, pigs, and chickens? If elephants, tigers, and other large, charismatic mammals are worthy of protection, why not bats, reptiles, insects, and other smaller, less endearing critters? Animals have long been beset by not only human cruelty but also human hypocrisy. What they need now, perhaps, is moral consistency.