Sir Joseph Dalton Hooker was born on June 30, 1817, in Halesworth, Suffolk, England, the second son of the distinguished botanist, Sir William Jackson Hooker (1785-1865).

He was a British botanist, explorer, and supporter of Darwin’s theories. At 15 he began to attend classes at the University of Glasgow, at first in classics and mathematics and later in medicine (M.D., 1839). Having a wide knowledge of botany based on work in his father's herbarium and on extensive plant-collecting in the British Isles, his degree enabled him to join the Naval Medical Service and to accompany a scientific expedition to the Antarctic (1839-1843). He became assistant director of the Royal Botanic Gardens at Kew (1855-1865). In 1865, he succeeded his father as director, serving in that capacity until his retirement in 1885. His last major botanical expedition to the Rocky Mountains and California (1877), led to the publication of several important papers concerning the relationship of American and Asian floras. His travels resulted in the discovery of species new to science, many of which were soon introduced to horticultural circles. He gained an international reputation as a pioneer plant geographer. He was elected a fellow of the Linnean Society in 1842 and of the Royal Society in 1847. He also served as president of the Royal Society (1873–1878) and was knighted in 1877.

In 1851, he married Frances Harriet Henslow (1825–1874) and in 1877, he married Hyacinth Symonds (1842–1921). He died on December 10, 1911, in Sunningdale, Berkshire, England.