V. Gunson Thorpe studied at King's College Hospital, London, and qualified as a member of the Royal College of Surgeons of England (MRCS) and a licentiate of the Society of Apothecaries of London (LSA). He joined the Royal Navy in 1886, served as surgeon captain during World War I (1914-1918) and retired in 1919 with the rank of surgeon rear-admiral. That same year he was honored as a Commander of the Order of the British Empire (CBE).
During his early years as a naval surgeon Thorpe visited various countries where he collected rotifers (a group of microscopic, multicellular animals found mainly in fresh water) and other microscopic fauna, which he studied in his spare time. His earliest investigations of rotifers, carried out in Australia, led to the publication of two papers, "On rotifera found in Brisbane" (1888) and "A list of Queensland rotifera" (1890), both in the Proceedings of the Royal Society of Queensland. During a visit to the Cape Colony he collected specimens in a pool near Simonstown and identified a new species, Brachionus furculatus, which he described in a paper on "New and foreign Rotifera" in the Journal of the Royal Microscopical Society (1891). Two years later he listed six more species which he had identified from the Cape, in a paper on "The rotifera of China" (Ibid, 1893). His work formed the start of rotifer research in southern Africa and was later continued by Thomas Kirkman*, William Milne*, Charles F. Rousselet* and others.
Thorpe contributed three further papers on rotifers: "Note on the recorded localities of rotifera" (Journal of the Quekett Microscopical Club, 1893), a note on the anatomy of the genus Brachionus (Ibid, 1893), and a note on a new species of the genus Pedalion from the Solomon Islands (Papers and Proceedings of the Royal Society of Tasmania, 1894-1895). His studies of other organisms were reported in "Description of a new species of Megalotrocha" (Journal of the Royal Microscopical Society, 1889), and "On the coloring power of Noctilucae" (a genus of protozoa; Ibid, 1891).