Discuss the role of cytochrome 'c' in establishing the evolutionary relationships among various species?
Answers
Evidence of common descent of living organisms has been discovered by scientists researching in a variety of disciplines over many decades, demonstrating the common descent of all life on Earth developing from a last universal ancestor. This evidence constructs the theoretical framework on which evolutionary theory rests, demonstrates that evolution does occur, and is able to show the natural processes that led to the emergence of Earth's biodiversity. Additionally, this evidence supports the modern evolutionary synthesis—the current scientific theory that explains how and why life changes over time. Evolutionary biologists document evidence of common descent by developing testable predictions, testing hypotheses, and constructing theories that illustrate and describe its causes.
Comparison of the DNA genetic sequences of organisms has revealed that organisms that are phylogenetically close have a higher degree of DNA sequence similarity than organisms that are phylogenetically distant. Genetic fragments such as pseudogenes, regions of DNA that are orthologous to a gene in a related organism, but are no longer active and appear to be undergoing a steady process of degeneration from cumulative mutations support common descent alongside the universal biochemical organization and molecular variance patterns found in all organisms. Additional genetic information conclusively supports the relatedness of life and has allowed scientists (since the discovery of DNA) to develop phylogenetic trees: a construction of organisms evolutionary relatedness. It has also led to the development of molecular clock techniques to date taxon divergence times and to calibrate these with the fossil record.