Woeseian revolution
The Woeseian revolution was the progression of the phylogenetic tree of life from two main divisions, known as the Prokarya and Eukarya, into three domains now classified as Bacteria, Archaea, and Eukaryotes. The discovery of the new domain stemmed from the work of biophysicist Carl Woese in 1997 from a principle of evolutionary biology designated as Woese's dogma. It states that the evolution of ribosomal RNA (rRNA) was a necessary precursor to the evolution of modern life forms.[1] Although the three-domain system has been widely accepted, the initial introduction of Woese’s discovery received criticism from the scientific community.
Phylogenetic implications
The basis of phylogenetics was limited by the technology of the time, which led to a greater dependence on phenotypic classification prior to advances that would allow for molecular methods of organization. This was a major reason why the dichotomy of all living things, being either animal or plant in nature, was deemed as an acceptable theory.[2] Without truly understanding the genetic implication of each organismal classification in phylogenies via nucleic acid sequencing of shared molecular material, the phylogenetic tree of life and other such phylogenies would no doubt be incorrect. Woese’s advances in molecular sequencing and phylogenetic organization allowed for a better understanding of the three domains of life - the Bacteria, Archaea, and Eukaryotes. In regards to their varying types of shared rRNA, that of the small subunit rRNA was deemed as the best molecules to sequence in order to distinguish phylogenetic relationships because of its relatively small size, ease of isolation, and universal distribution.[3]
Controversy
This reorganization caused for an initial push back, being accepted nearly a decade after its publication.[4] Possible factors that led to the initial criticism of the discovery include Woese’s oligonucleotide cataloging of which he was one of “only two or three people in the world” to be able to execute this method let alone read the films. Also, Woese’s background was in physics whereas most of the research was being done in the realm of microbiologists.[5]
References
- ^ Bothamley, Jennifer (2002). Dictionary of Theories. p. 557.
- ^ Woese, C.R.; Kandler, O.; Wheelis, M.L. (1990). "Towards a natural system of organisms: Proposal for the domains Archaea, Bacteria, and Eucarya". Proceedings of the National Academy of Sciences of the United States of America. 87 (12): 4576–79. Bibcode:1990PNAS...87.4576W. doi:10.1073/pnas.87.12.4576. PMC 54159. PMID 2112744.
- ^ Woese, C.R. (1996). "Phylogenetic trees: Whither microbiology?". Current Biology. 6 (9): 1060–63. doi:10.1016/s0960-9822(02)70664-7. PMID 8805350.
- ^ Sapp, Jan (2009). The new foundations of evolution: on the tree of life. Oxford University Press.
- ^ Morell, V (1997). "Microbial Biology: Microbiology's scarred revolutionary". Science. 276 (5313): 699–702. doi:10.1126/science.276.5313.699. PMID 9157549.