James Geikie (1839-1915) was the leading British authority on Pleistocene geology. He developed the theory, through observations in Scotland and Continental Europe, that during ice-ages mild inter-glacial periods interrupted the glacial period as a whole. He originated the current belief that human habitation continued in Europe throughout the glacial period.

Geikie undertook classes at the University of Edinburgh while working in a printer's office. In 1861 he took up a position, with the Geological Survey, mapping glacial drift deposits in Central Scotland. This was supervised by his brother Archibald Geikie (1835-1924). Geikie made his reputation with the book The Great Ice Age and its Relation to the Antiquity of Man, ( 1874) , the 3rd edition of which was fully revised in 1894. In 1882 he succeeded his brother, Sir Archibald Geikie as the second Murchison Professor of Geology and Mineralogy at the University of Edinburgh. While undertaking his duties two seminal textbooks were published: Outlines of Geology, ( 1886) and Structural and Field Geology, ( 1905) .

In 1889 Geikie was awarded the Murchison medal by the Geological Society, London and the Brisbane Medal by the Royal Society of Edinburgh. He was a founder member of the Royal Scottish Geographical Society and the President from 1904-1910. For a period he also edited the magazine. He was elected fellow of the Royal Society, London, in 1875 and was President of the Royal Society of Edinburgh when he died.