(1792-1867) Born in Newcastle, Joshua was one of the founder members of the Natural History Society and he gained international recognition for his work on nudibranchs (sea slugs) and molluscs.
Joshua Alder was born in Dean Street, Newcastle where his parents were the owners of a grocery store. He joined the business when he was fifteen, after private education in Newcastle and Tanfield Lee. His love of natural history came later in his life when he joined the Literary and Philosophical Society of Newcastle in 1815 and met a group of local naturalists.
After studying geology and botany for a while he turned his attention to British molluscs, land and freshwater snails, producing many papers on the subject. He was, with Albany Hancock, a founder member of the Natural History Society of Northumberland, Durham and Newcastle upon Tyne in 1829.
His collaboration with Albany Hancock on their book The Monograph of the British Nudibranchiate Mollusca published between 1844 and 1855 was to bring him international recognition. He travelled all over Britain collecting specimens for the book and made many fine drawings of his own, which can be seen in the archive collections of the Natural History Society of Northumbria at the Hancock Museum.
Joshua Alder was a gentleman, a scholar and a well respected North East naturalist.