Edna Plumstead

Edna Pauline Plumstead , née Janisch, (born September 15, 1903 in Cape Town , † September 23, 1989 in Johannesburg ) was a South African paleobotanist . She was a leading expert on the geology and paleobotany of Gondwana . Your official botanical author abbreviation is “ Plumst. ".

Life

Plumstead, who moved to Johannesburg with her family at the age of eight and attended school there, studied geology at the University of Witwatersrand in Johannesburg from 1921 with a bachelor's degree in 1924 and a master's degree in 1926 with distinction (for him she also received the first Corstorphine Medal of the Geological Society of South Africa). She then went on a scholarship to Cambridge University , where she studied South African coal under Hamshaw Thomas (1885–1962), a student of the retired Albert Charles Seward . In 1928 she was forced to abandon her studies before completing her doctorate, as the University of Witwatersrand called her back as a lecturer . Even then she became a supporter of Alfred Wegener's theory of continental drift . She found considerably more similarities in the paleoflora of the South African coal she was studying to that in Australia than to that, for example, in England. Her convictions solidified in 1929 when she attended the International Geological Congress, which was then held in South Africa, with the participation of supporters of continental drift such as Alexander Du Toit and Seward. In 1934 she married the mining engineer Edric Plumstead and became a housewife and mother of five children. In 1947 she returned to the University of Witwatersrand as a senior lecturer after a shortage of lecturers due to World War II. From 1965 she was at the Bernard Price Institute for Palaeontological Research at the University of Witwatersrand.

plant

Studying the Gondwana plant fossils found in Antarctica in the 1960s, Plumstead became a staunch advocate of the continental drift theory due to its similarity to other plant fossils in South Africa, India, Australia and South America, all parts of the former Gondwana continent. The key fossil Glossopteris has long been an argument of the proponents of this theory, which also found the greatest support among geologists in countries such as South Africa, which geologically belonged to Gondwana. Opponents criticized the lack of a plausible mechanism for the migration of the continents; the theory did not gain acceptance until the late 1960s, primarily through marine geological studies. Plumstead and soon afterwards also vertebrate paleontologists such as the South African James Kitching ensured early support from the paleontological side through detailed investigations.

Plumstead also became known for finding the first reproductive organs of Glossopteris in 1950. She discovered them in the fossil collection of the collector and carpenter SF le Roux when she and students visited the type locality of the stone quarries of the Vereeniging Brick and Tile Co. in the Karoo main basin in Vereeniging near Johannesburg. She then arranged for a scholarship for Le Roux to study palaeobotany and collected regularly with it (her collection is now in the Bernard Prince Institute). The discovery of the reproductive organs also led to a revision of the classification of the Glossopteris species, which had previously only been classified according to the leaves. At first she ordered Glossopteris the seed ferns , but then she said, in the genus Scutum evidence of their bisexual nature to have found and considered them as precursors of the angiosperms (angiosperms).

Honors

Edna Plumstead was a Fellow of the Royal Society of South Africa . In 1973 she received the South Africa Medal in Gold and she received the Chrestien Mica Gondwanaland Medal from the Geological Society of India . The Plumstead Valley in Antarctica has been named after her since 1964.

Fonts

• Coal in South Africa, Witwatersrand University Press 1957
• Fossil floras of Antarctica, London: Trans-Antarctic Expedition 1955–1958, Scientific Report Geology, Volume 9, 1962, pp. 1–154 (with the appendix by Richard Kräusel on fossil woods)
• Palaeobotany of Antarctica, in RJ Adie, Antarctic Geology, North Holland 1964, 637-654
• Glimpses into the history and prehistory of Antarctica, Antarktiese Bulletin, 9, 1965, 1-7
• Three Thousand Million Years of Plant Life in Africa, Johannesburg: Geological Society of South Africa, 1969
• A new assemblage of plant fossils from Milorgfjella, Dronning Maud Land, British Antarctic Survey, Scientific Report 83, 1975, 1-30

literature

• Henry R. Frankel: The continental drift controversy. Volume 1: Wegener and the early debate, Cambridge University Press 2012 (Chapter 6.3: Edna Plumstead and her support for continental drift)
• Obituary by JM Maguire, Transactions Royal Society South Africa, 47, 1990, 355-357

Individual evidence

1. ↑ Plumstead recalled that in Cambridge in the mid-1920s, the greatest resistance to the theory discussed there in the geological faculty belonged to the physicist Harold Jeffreys , who criticized precisely this lack of a physical explanation
2. ↑ Plumstead, Description of two new genera and six new species of fructifications borne on Glossopteris leaves from South Africa, Transactions Geological Society of South Africa, Volume 55, 1952, pp. 281-328
3. ↑ Plumstead, Further fructifications of the Glossopteridae and a provisional classification based on them, Trans. Geol. Soc. South Africa, Vol. 61, 1958, pp. 52-74
4. ↑ Plumstead: Bisexual fructifications borne on Glossopteris leaves from South Africa, Palaeontographica B, Volume 100, 1956, pp. 1-25