Bio
9/16/2012
The theory of a common ancestor is universally accepted the origin of all life on Earth. In the article, “The Proof is in the Proteins: Tests Supports Universal Common Ancestor for All Life”, by Katherine Harmon, a scientist by the name of Douglas Theobold carried out statistical analysis on 23 preserved proteins that were preserved over three major domains of life. The result of these analyses supported Darwin’s evolutionary theory, by demonstrating that the protein sequences of life today came from a common universal ancestor rather than separate individual ancestors. However, today doubt in this theory still exists. This stems from achieved knowledge of lateral gene exchange and the discovery of the third major domain of life known as Achaea. While researching this topic, Theobold took lateral gene exchange into consideration and this ended up providing the most evidence for Darwin’s universal common ancestor theory. This article relates to the biology class topic of life’s origin. Darwin postulated that all life that exists has descended from a common ancestor and that through the natural selection process, species adapted and evolved to bring about life that exists today. Life originates from the origin of cells since cells are the fundamental units of all life on Earth today and all cells are produced from cells that previously existed. The 3 major domains of life had a common ancestor whose genetic material consisted of DNA, which could be translated to RNA and then transcribed to proteins. Eukaryotes have evolved from prokaryotes. Evidence of a common ancestor lies in the similarities of the DNA sequences of genes. Although, not noticeable by the naked eye. All life today is