Today in Science History

From Today in Science History:

William Joscelyn Arkell (Born 9 Jun 1904; died 18 Apr 1958). English paleontologist, an authority on Jurassic fossils (those dating from 208 to 144 million years ago). Arkell taught at Trinity College, Cambridge University. His work includes the classification of Jurassic ammonites and an interpretation of the environments of that period. He wrote Jurassic Geology of the World (1956), which critically reviewed the information dispersed throughout the world’s enormous literature on the world’s Jurassic stratigraphy. He made numerous contributions to knowledge of the Jurassic stratigraphy, and gradually stabilized many stratigraphically significant zonal assemblages. In 1946, his “Standard of the European Jurassic” advocated a commission formulate a code of rules for stratigraphical nomenclature.

Wilhelm Roux (Born 9 Jun 1850; died 15 Sep 1924). German zoologist who was a founder of experimental embryology, by which he studied how organs and tissues are assigned their structural form and functions at the time of fertilization. He experimented with frog eggs (1880s). He thought that mitotic cell division of the fertilized egg is the mechanism by which future parts of a developing organism are determined. He destroyed one of the two initial subdivisions (blastomeres) of a fertilized frog egg, obtaining half an embryo from the remaining blastomere. It seemed to him that determination of future parts and functions had already occurred in the two-cell stage and that each of the two blastomeres had already received the determinants necessary to form half the embryo. His theory was later negated by Hans Driesch.

Brown’s Australian voyage ends In 1803, Robert Brown (1773-1858), botanist on Matthew Flinders’ vessel HMS Investigator ended a long voyage of discovery in Port Jackson, Australia. From the ship’s arrival at the continent’s western coast (then known as New Holland or Terra Australis) in Dec 1801, age 27, he had made an enormous collection of plant samples which he classified and named. He published the results in his famous Prodromus Florae Novae Hollandiae in 1810, now a classic in systematic botany, although it was unillustrated, and failed to sell well at the time. He was the leading British botanist to collect in Australia in the early 19th century. He also described Brownian motion: random motion observed by microscope of pollen immersed in water (1827).

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