In “The Sound of the Sea: Seashells and the Fate of the Oceans,” Cynthia Barnett presents us with a glittering Wunderkammer for our age, a staggeringly varied history — scientific, cultural, philosophical and economic — of one of the most beloved and enduring natural objects on Earth: the seashell. To the 16th-century European collector, a Wunderkammer housed a collection of natural and precious objects ranging from the geological, archaeological, ethnological and religious to new works of art. Shells, at one time or another, seem to have represented all of these things, and Barnett’s book buzzes with histories spanning a barely comprehensible 800 million years.

Barnett begins her narrative 100,000 years ago. A collection of fossilized cockle shells, each with a natural hole in the top, perfect for stringing into a necklace “or some other intention,” was found fused into the floor of a cave overlooking Cartagena Harbor in Spain. The find suggests an enlightening alternative to our long-held notion of Neanderthals. Were these hominids not the “dim-witted brutes” we have supposed but rather avid collectors who had an “appreciation for seashells beyond food”? Barnett imagines a “human cousin,” a Neanderthal girl, walking along a Mediterranean beach, engaged in a pastime which in 1956 The Washington Post described as “the nation’s

fastest-growing hobby.”

Each chapter is named after a different seashell. Conch shells fashioned into trumpets were found at the Peruvian temple complex at Chavín de Huántar. Vents built into the stone structure, in addition to providing fresh air, may have given the oracle at Chavín a highly engineered voice “worthy of the Wizard of Oz” when the shell trumpets were played inside them.

Pre-Columbian painted animal sculptures, which attest, in their lifelike accuracy, to the sophistication and skill of their creators, were found at Key Marco, Fla., along with countless lightning whelk beads, pendants and ear buttons. This site, and the shell mounds of southwestern Florida, were “built over or hauled off for roads or construction fill.” Also destroyed were the clues they held to people who had built the first great North American cities.

In California, Indigenous shell mounds also “archived the lives and communities of prehistoric people.” When human remains were found buried among the shells, the Berkeley Daily Gazette, in 1942, informed its readers that “a shell mound was the combination burial ground and garbage dump of California’s first settlers,” implying something at worst barbaric or at best careless in this funerary practice. Michelle LaPena of California’s Pit River Tribe, and Corrina Gould of the Confederated Villages of Lisjan, observed that the newspaper “reflected a fundamental disconnect that persists to this day,” namely that “where many non-Indians saw a boundary between people and nature . . . Native people believed all of nature — plants and animals as well as rocks and shells . . . possessed spiritual power.” It would be the greatest honor, even today, to be buried among seashells.

One of the most captivating narratives in “The Sound of the Sea” is that of the Samuel family of London’s East End, who in 1833 opened a small curio shop on the banks of the River Thames trading in “small Shells for Ladies’ Work.” Following a seaside holiday, Marcus Samuel came up with the idea of selling shell-encrusted boxes as souvenirs. He also imported china bowls, olive oil, ostrich feathers and sandalwood. His children inherited and expanded the Samuel business and, in honor of their father’s abiding passion, named the new company the Shell Transport and Trading Company. With the opening of the Suez Canal, Marcus Samuel Jr. took the opportunity to trade directly within Asia at a time when most merchants still imported bulk goods to England. However, it was his collaboration with the marine engineer Fortescue Flannery that led to the company’s domination of the burgeoning oil trade. Flannery designed a ship for Samuel Jr., the Murex, which was to become the modern oil tanker. The company is known today as Royal Dutch Shell.

Barnett’s painstaking attention to detail renders particularly poignant the irony of the impact that the oil trade has had on marine life. The biocide paint tributyltin, known as TBT, protected Shell tankers from accruing algae, barnacles and mussels, but it also caused female murex mollusks to change their gender, impairing their ability to spawn. Murex mollusks are the only source of the ancient dye, documented by Pliny, known as Tyrian purple. Is the “fundamental disconnect” that separates human from other-than-human species anywhere more visible than in the burning of fossil fuels and the release of carbon, which had been safely stored below the ground for millennia, into the Earth’s atmosphere? Approximately a third of this carbon is dissolved almost immediately into the sea, resulting in acidification that threatens all manner of marine species.

Barnett reveals another “fundamental disconnect” separating human from human in the exchange of Maldivian cowrie shells for living people. She recounts that, as a currency, cowries “have circulated longer than any other single coin or paper money in history.” In West Africa “they purchased an estimated third of the enslaved people forced to the Americas.” The part the shells played in the enslavement and forced transportation of people predates the Christian era by 1,000 years. When shells were used as money in the sale of humans, Barnett reminds us, they showed us at our worst.

Barnett had “set out to listen to seashells as chroniclers of nature’s truth.” Shells have helped us to calculate the age of the Earth and to better understand deep time, evolution and extinction. They have shown us that human beings are relative newcomers to the planet, yet at the same time that our earliest ancestors, before we were even human, collected seashells seemingly for the joy of it. Shells have “revealed how humans have altered the climate and the sea — down to its very chemistry.” Yet some shellfish species are trying to adapt to those rapidly occurring changes.

“The Sound of the Sea” is a glorious history of shells and of those who have loved shells. It is a history of fascination and of shame. It stretches our capacity to absorb new knowledge. It is as complex, multichambered and beautiful as its subject, and if Barnett can awaken our sense of wonder, then perhaps there is hope for jump-starting our collective sense of responsibility toward the oceans and one another.

The Sound of the Sea

Seashells and the Fate of the Oceans

By Cynthia Barnett

417 pp. $27.95