Thomas Davidson (May 17, 1817 - October 14, 1885), British palaeontologist, was born in Edinburgh.

His parents possessed considerable landed property in Midlothian. Educated partly in the university of Edinburgh and partly in France, Italy and Switzerland, and early acquiring an interest in natural history, he benefited greatly by acquaintance with foreign languages and literature, and with men of science in different countries.

He was induced in 1837, through the influence of Leopold von Buch, to devote his special attention to the brachiopoda, and in course of time he became the highest authority on this group. The great task of his life was the Monograph of British Fossil Brachiopoda, published by the Palaeontographical Society (1850-1886). This work, with supplements, comprises six quarto volumes with more than 200 plates drawn on stone by the author.

He also prepared an exhaustive memoir on Recent Brachiopoda, published by the Linnean Society. He was elected FRS in 1857. He was awarded in 1865 the Wollaston medal by the Geological Society of London, and in 1870 a Royal medal by the Royal Society; and in 1882 the degree of LL.D. was conferred upon him by the university of St Andrews.

He died at Brighton on the 14 October 1885, bequeathing his fine collection of recent and fossil brachiopoda to the British Museum.

See biography with portrait and list of papers in Geol. Mag. for 1871, p. 145.