Palaeontologist. Born in Edinburgh, Davidson was the son of a wealthy Midlothian land-owning family. He was educated at the University of Edinburgh and completed his studies on the continent. Having gained an early interest in natural history, Davidson became an expert in Brachiopod fossils (a marine bivalve). Working at the University of Edinburgh, he completed a definitive six-volume Monograph of British Fossil Brachiopoda (1850-86). He was elected a Fellow of the Royal Society (1857) and awarded its Royal Medal (1870) and also received the Wollston Medal from the Geological Society of London (1865). He was awarded an honorary degree by the University of St. Andrews in 1882.
Davidson died in Brighton (England) and left his extensive collection of fossils to the British Museum.