William Healey Dall was born on August 21, 1845, in Boston, Massachusetts.

He was an American naturalist, a prominent malacologist, and one of the earliest scientific explorers of interior Alaska. After graduating from high school in 1863, he took a keen interest in mollusks and became a pupil of Louis Agassiz of Harvard's Museum of Comparative Zoology, in natural science. He completed numerous expeditions to Siberia and Alaska. He described many mollusks of the Pacific Northwest of America and was for many years America's preeminent authority on living and fossil mollusks. Dall also made substantial contributions to ornithology, vertebrate and invertebrate zoology, physical and cultural anthropology, oceanography, and paleontology. He also carried out meteorological observations in Alaska for the Smithsonian Institution. He was a prolific author, having published over 1,600 papers, reviews, and commentaries. He holds the distinction of having described the second largest number of species of mollusks (nearly 4,000). He was elected member of most of the U.S. scientific societies, vice-president of the American Academy of Arts and Sciences (1882, 1885), a founder of the National Geographic Society, and the Philosophical Society of Washington. In 1897, he was elected to the National Academy of Sciences. He was a Foreign Member of the Geological Society of London. Mount Dall, an 8,399-foot (2,560 m) peak in the Alaska Range, now in Denali National Park and Preserve was named after Dall by the U.S. Geological Survey in 1902.

In 1880, he married Annette Whitney (1859-1943). He died on March 27, 1927, in Washington, D.C.