Hermann Franz (often Francis) Becker qualified as Doctor of Medicine (MD) at the University of Jena, Germany, in 1862. He emigrated to the Cape of Good Hope in 1869, at which time he was already described as "a gentleman of great zoological attainments" by the director of the South African Museum, E.L. Layard*. He classified and arranged the museum's collection of Coleoptera (beetles) soon after his arrival. In June 1869 he was licensed to practice medicine and was soon appointed as medical officer at Port Alfred. In 1874 he moved to Grahamstown where he started a private practice. He remained there for most of his life, though in 1884 he was a resident of Bathurst.
Becker donated many insects and other material to the Albany Museum in Grahamstown, starting in 1873 with part of a named collection of beetles. A later director of the museum, John Hewitt*, described him as "a man of vigorous intellect, deeply interested in natural history, [who] soon became prominent in the museum world", while Dr. S. Schonland*, director from 1889, acknowledged his thorough knowledge of South African insects. Becker published little or nothing, his scientific contributions consisting mainly of his collecting activities. His early donations to the Albany Museum included some skulls of smaller cetaceae (1874), more insects, particularly butterflies and moths (1875, 1876), English devonian fossils (1878), a collection of fish and other marine animals (1880), local insects plus birds from other countries (1885). In 1879 he found a species of tape worm (which was known to be common in dogs) in an ostrich, in which this particular species had not been known to occur. He assisted the curators, B.J. Glanville* and later Miss M. Glanville*, with the museum's collections during these years and in 1884 donated a "varied and beautiful collection of shells", numbering 2351 specimens. According to Miss Glanville, conchology was becoming a speciality of the museum under his care. Roland Trimen* of the South African Museum, Cape Town, mentioned him as a contributor of butterflies from the eastern districts, in the preface of his book, South African butterflies... (1887-1889). Becker's wife, Mary Julia Becker*, who shared his interest in natural history, died during 1885. The two of them presented a collection of 9718 Coleoptera (beetles) from Port Alfred to the Albany Museum at some time before 1883.
By 1883 Becker was a member of the management committee of the Literary, Scientific, and Medical Society, which owned and managed the Albany Museum. He was one of its vice-presidents by 1892, and succeeded Dr. W.G. Atherstone* as president when the latter died in 1898. He resigned as president in 1905, but remained a member of the committee for some further years and was associated with the museum until his death in 1917, for example, he was chairman of the museum's Board of Trustees in 1910. Although his scientific activities appear to have slowed down somewhat following the death of his wife, his interests were revived in due course. In 1892 he presented South African marine algae to the Albany Museum, while in 1897 he revised the museum's shell collection with the help of the young S. Juby*. During this year he also visited the Cape Government Herbarium in Cape Town to study the algae collected by C.F. Ecklon* and C.L.P. Zeyher*. The curator of the Herbarium, P. MacOwan* (who wrongly gave Becker's initials as C.F.) described him at this time as "a specialist in these difficult plants" and later as an "accomplished algologist of Grahamstown". On his return to Grahamstown Becker presented the herbarium with a valuable series of Cape algae. He donated a collection of 185 European fresh water algae to the Albany Museum during the same year, with 108 more following in 1898. He also resumed his donations of molluscs to the museum in 1898 and 1899, those of the latter year having been named by G.B. Sowerby*. In 1901 he returned to the Cape Government Herbarium and revised its Australian algae. He also donated many more molluscs to the Albany museum, followed by his whole collection of mounted Hydrozoa in 1904. During these and later years he built up a huge world-wide collection of shells, not only through his own collecting activities, but also by exchanging and purchasing specimens. One of the collections he acquired was that of Mrs. A. Filmer*. Sowerby named, among others, new species of Gibbula and Primovula in Becker's honour. In 1911 he identified sea shells for the Albany Museum, and the next year presented plants to its herbarium. His shell collection, together with his library, was bequeathed to the Transvaal Museum, but later transferred to the Natal Museum.
Becker participated in the activities of various scientific societies, but did not play a leading role in them. He served on the first council of the Eastern Province Branch (founded February 1885) of the first South African Medical Association, and was a member of the committee of the Grahamstown and Albany Horticultural Society in 1897. He was a founding member of the South African Association for the Advancement of Science in 1902. In 1904 he joined the South African Philosophical Society and remained a member when it became the Royal Society of South Africa in 1908. He was a fellow of the Linnaean Society (elected in 1866) and of the Society of Arts, and a member of the Botanic Society of Berlin.