Elso S. Barghoorn

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Elso Sterrenberg Barghoorn (born June 30, 1915 in New York City , † January 27, 1984 ) was an American paleontologist (paleobotany). He was an internationally recognized expert on Precambrian algae fossils. He found some of the oldest fossils ever and expanded the timescale of known fossil finds from around 650 million years in the 1950s to 2 billion years. Its official botanical author abbreviation is “ Bargh. ".

life and work

Barghoorn, who grew up in Ohio , studied at Miami University (Bachelor in 1937) in Ohio and then botany at Harvard University , where he received his doctorate in 1941 with the plant anatomist Irving W. Bailey . As a post-doctoral student, he conducted research in the Botanical Garden of Harvard University in Cienfuegos , Cuba . After five years at Amherst College from 1941, where his interest in paleobotany was awakened by Edward Hitchcock while studying a fossil collection from the Tertiary of Vermont , he returned to Harvard, where he became professor of paleobotany in 1946. He was Fisher Professor of Natural History and curator of the university's paleobotanical collection in the Gray Herbarium .

In the 1950s, Barghoorn discovered fossil blue-green algae colonies on Lake Superior (Gunflint Iron Formation, Ontario) that were around two billion years old. Before that, he had received shiny black rock samples from Michigan and Canada from geologist Stanley Tyler (professor at the University of Wisconsin ) in 1950 (through Robert Shrock) , which he was supposed to investigate as a paleobotany expert for coal content. The surrounding rock (slate and chert ) also contained amber-like inclusions and impressions in a concentric fan shape reminded Barghoorn of the recent blue algae Rivularia. In 1953, Barghoorn finally received samples from Tyler with well-preserved microfossils (from cyanobacteria and iron oxidizing bacteria) from Lake Superior.

After Barghoorn and Tyler's breakthrough in 1954, nothing happened in this area for a long time, but their results were confirmed in the 1960s. Tyler died in 1963, and Barghoorn was embroiled in a priority dispute with Preston Cloud , which was so settled that both published their findings in 1965. Finds at Alice Springs (Bitter Springs Formation) were added that were about as old as those of the Gunflint Formation.

In the 1960s, he discovered fossils that were a billion years older and in 1977 with Andrew Knoll, fossils that were 3.4 billion years old in South Africa. He found evidence of the origin of life on earth at the earliest possible point in time immediately after environmental conditions existed that made life possible at all.

He was also interested in studying extraterrestrial life early on and was involved in a 1981 report by the Space Science Board of the National Academy of Science (Origin and Evolution of Life - Implications for the Planets: A Scientific Strategy for the 1980s, Washington DC 1981, Lynn Margulis was also involved ).

He was elected to the American Academy of Arts and Sciences in 1950, the National Academy of Sciences in 1967 and the American Philosophical Society in 1978 . In 1972 he received the Charles Doolittle Walcott Medal .

His doctoral students include J. William Schopf and Alfred Traverse .

He was married three times and had two sons from his first marriage, one of whom (Steven Barghoorn) became a vertebrate paleontologist.

Fonts

  • The oldest fossils . Scientific American, May 1971.

Individual evidence

  1. Barghoorn, Tyler Occurrence of structurally preserved plants in Pre-Cambrian rocks of the Canadian Shield , Science, Volume 119, 1954, pp. 606-608
  2. Barghoorn, Tyler Science, Volume 147, 1965, pp. 563-577. According to Schopf Solution to Darwin's dilemma: Discovery of the missing Precambrian record of life , Proc. NAS, 97, 2000, 6947
  3. ^ Barghoorn, J. William Schopf, Science, Volume 150, 1965, p. 337
  4. Barghoorn, JW Schopf Microorganisms three billion years old from the Precambrian of South America , Science, Volume 152, 1966, pp. 758-763
  5. Barghoorn, Knoll Archean microfossils showing cell division from the Swaziland System of South Africa , Science, Volume 198, 1977, pp. 396-398

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