Parallel convergent evolution

The comparison of protein folds has proved to be difficult the three-dimensional structures are frequently complicated, and quite significant differences can exist between structures that are, on the basis of sequence similarity, clearly related in evolutionary terms. On the other hand structures may sometimes resemble each other very closely, but fail to display any sequence similarity the classic example of this is the parallel beta barrel structure which has now been found in more than twenty proteins with no amino-acid sequence homology [35], In these cases the interpretation of the meaning of a similarity can be less than straightforward it may indicate that the proteins are evolutionary related ( divergent evolution ), that they are unrelated but have evolved similar structures because they carry out similar functions ( convergent evolution ) or the common structure may simply be a particularly stable one that is adopted by a large number of proteins. In addition to three similarities between complete protein folds, there may also be partial similarities. 

Nature sometimes solves identical problems with apparently quite different solutions. Important examples of such a convergent evolution at the molecular level are the functional parallels between iron and copper centers in bioinorganic chemistry. The dioxygen-carrier proteins of different organisms may, for instance, be based on mononuclear iron tetrap5rrrole complexes or in contrast may involve dinuclear copper sites 10). S5mthetic chemistry can even go a step fiuther and try to mimic basic... 

Austin DF (1998) Parallel and convergent evolution in the Convolvulaceae. In Mathews P, Sivadasan M (eds) Diversity and taxonomy of tropical flowering plants. Mentor Books, Calicut, India, pp 201-234... 

Fong SS, Joyce AR, Palsson BO (2005b) Parallel adaptive evolution cultuies of Escherichia coli lead to convergent growth phenotypes with different gene expression states. Genome Res 15 1365-1372... 

See also Astrobiology Evolution, convergent Evo-hitiorr, divergent Evolution, evittarce of Evolutiar, parallel Evolutionary charge, rate of. 

These somewhat disparate technical developments progressed more or less in parallel but converged during the evolution of Raman instrumentation starting approximately in 1986. A major result was the emergence of integrated Raman spectrometers that incorporated laser, spectrometer, sampling accessories, and software into a complete system. These newer instruments were not only much more capable than previous systems, but they were also more reliable... 

Weng, J.K., Banks, J.A., Chappie, C. Parallels in lignin biosynthesis a study in Selaginella moellendorffii reveals convergence across 400 million years of evolution. Commun. Integr. Biol. 1, 20-22 (2008)... 

Islands separated by water can show the same kind of convergence as continents, but on a smaller scale. A group studying lizard evolution on four Carribean islands published a paper with a title that says it all Exceptional Convergence on the Macro evolutionary Landscape in Island Lizard Radiations. Scientists don t put exceptional in their title unless they really mean it. All four islands developed similar lizard features in parallel, showing that many features of large-scale radiations maybe surprisingly predictable. ... 

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