IntroductionThe Archaea and the origin of life. The word Archaea originates from the Greeks and means beginning. In this essay we will look at the discoveries of Archaea and why they are classified as Prokaryotes and what the actual evolutionary relationship of Archaea is with Eukaryotes and Bacteria. We will examine the different points of view within the scientific community regarding the number of domains. Whether three or two domains of life fit into the Tree of Life. We will look at some research that has evidence to support the same. This essay will therefore look at the Habitat of Archaea: why many Archaea are classified as extremophiles and how these are not just bacteria and that extremophiles are a diverse group and capable of living in extreme conditions on earth. We will then talk about the Archaea and how they were originally classified as bacteria. Finally, this essay will examine how Archaea function in a symbiotic relationship in the digestive tract of termites. Reasons why Archaea were classified as prokaryotes: Before the latter part of the twentieth century, Archaea were classified as an unusual group of bacteria called Archaeabacteria, new research pioneered by Dr. Carl Woese and colleagues in the 1990s. 70 which led to work with phylogenetics on ribosomal RNA (rRNA) sequence comparisons using a technique using 16S rRNA sequencing. Furthermore their information transfer systems or (DNA replication, transcription, translation) (Henderson's, 1998). This is mainly involved in the translation of active proteins, this helped adapt the Archaea to their own domain although they still have similar traits to their Eukarya counterparts. Another different feature of Archaea is the distinctive method of...... middle of paper...... E., Reid, W., Roterman, C., Sweeting, C., Thatje, S., & Zwirglmaier , K. (2012). The discovery of new deep-sea hydrothermal vent communities in the Southern Ocean and implications for biogeography PLoS Biology, 10 (1) DOI: 10.1371/journal.pbio.1001234Lawrence, E (1998). Henderson's Dictionary of Biological Terms, Eleventh Edition, Appendix 6, p.683Syvanen, M. (2002). Ribosomal RNA evolution rates are uniquely accelerated in eukaryotes. Journal of Molecular Evolution, 55(1), 85-91. doi: http://dx.doi.org/10.1007/s00239-001-2306-9T. D. Brock, M. T. Madigan, J. M. Martinko, and J. Parker. 1994. Biology of Microorganisms, 7th ed. (New Jersey: Prentice Hall). Yutin, N., Makarova, K. S., Mekhedov, S. L., Wolf, Y. I., & Koonin, E. V. (2008). The deep roots of the Archaea of ​​eukaryotes. Molecular Biology and Evolution, 25(8), 1619-30. doi: http://dx.doi.org/10.1093/molbev/msn108