Darwinism's predictions
A fundamental concept in evolutionary theory is the inheritance of genetic variations via blood lines. (Forbes) This so-called vertical transmission of heritable material means that genes, and genomes in general, should fall into a common descent pattern, consistent with the evolutionary tree. Indeed, such genes are often cited as a confirmation of evolution. But as more genomic data have become available, an ever increasing number of genes have been discovered that do not fit the common descent pattern because they are missing from so many intermediate species. (Andersson and Roger 2002; Andersson and Roger 2003; Andersson 2005; Andersson, Sarchfield and Roger 2005; Andersson 2006; Andersson et. al. 2006; Andersson 2009; Andersson 2011; Haegeman, Jones and Danchin; Katz; Keeling and Palmer; Richards et. al 2006a; Richards et. al 2006b; Takishita et. al.; Wolf et. al.)
This type of pattern is also found for genome architecture features which are sporadically distributed and then strikingly similar in distant species. In fact these similarities do not merely occur twice, in two distant species. They often occur repeatedly in a variety of otherwise distant species. This is so widespread that evolutionists have named the phenomenon “recurrent evolution.” As one paper explains, the recent explosion of genome data reveals “strikingly similar genomic features in different lineages.” Furthermore, there are “traits whose distribution is ‘scattered’ across the evolutionary tree, indicating repeated independent evolution of similar genomic features in different lineages.” (Maeso, Roy and Irimia)
One example is the uncanny similarity between the kangaroo and human genomes. As one evolutionist explained: “There are a few differences, we have a few more of this, a few less of that, but they are the same genes and a lot of them are in the same order. We thought they’d be completely scrambled, but they’re not.” (Taylor)
It is now well recognized that this prediction has failed: “Vertical transmission of heritable material, a cornerstone of the Darwinian theory of evolution, is inadequate to describe the evolution of eukaryotes, particularly microbial eukaryotes.” (Katz) And these sporadic, patchy patterns require complicated and ad hoc scenarios to explain their origin. As one paper explained, the evolution of a particular set of genes “reveals a complex history of horizontal gene transfer events.” (Wolf et. al.) The result is that any pattern can be explained by arranging the right mechanisms. Features that are shared between similar species can be interpreted as “the result of a common evolutionary history,” and features that are not can be interpreted as “the result of common evolutionary forces.” (Maeso, Roy and Irimia)
These common evolutionary forces are complex and must have been created by evolution. They can include horizontal (or lateral) gene transfer, gene loss, gene fusion, and even unknown forces. For instance, one study concluded that the best explanation for the pattern of a particular gene was that it “has been laterally transferred among phylogenetically diverged eukaryotes through an unknown mechanism.” (Takishita et. al.) Even with the great variety of mechanisms available, there still remains the unknown mechanism.
References
Andersson, J., A. Roger. 2002. “Evolutionary analyses of the small subunit of glutamate synthase: gene order conservation, gene fusions, and prokaryote-to-eukaryote lateral gene transfers.” Eukaryotic Cell 1:304-310.
Andersson, J., A. Roger. 2003. “Evolution of glutamate dehydrogenase genes: evidence for lateral gene transfer within and between prokaryotes and eukaryotes.” BMC Evolutionary Biology 3:14.
Andersson, J. 2005. “Lateral gene transfer in eukaryotes.” Cellular and Molecular Life Sciences 62:1182-97.
Andersson, J., S. Sarchfield, A Roger. 2005. “Gene transfers from nanoarchaeota to an ancestor of diplomonads and parabasalids.” Molecular Biology and Evolution 22:85-90.
Andersson, J. 2006. “Convergent evolution: gene sharing by eukaryotic plant pathogens.” Current Biology 16:R804-R806.
Andersson, J., R. Hirt, P. Foster, A. Roger. 2006. “Evolution of four gene families with patchy phylogenetic distributions: influx of genes into protist genomes.” BMC Evolutionary Biology 6:27.
Andersson, J. 2009. “Horizontal gene transfer between microbial eukaryotes.” Methods in Molecular Biology 532:473-487.
Andersson, J. 2011. “Evolution of patchily distributed proteins shared between eukaryotes and prokaryotes: Dictyostelium as a case study.” J Molecular Microbiology and Biotechnology 20:83-95.
Haegeman, A., J. Jones, E. Danchin. 2011. “Horizontal gene transfer in nematodes: a catalyst for plant parasitism?.” Molecular Plant-Microbe Interactions 24:879-87.
Katz, L. 2002. “Lateral gene transfers and the evolution of eukaryotes: theories and data.” International J. Systematic and Evolutionary Microbiology 52:1893-1900.
Keeling, P., J. Palmer. 2008. “Horizontal gene transfer in eukaryotic evolution,” Nature Reviews Genetics 9:605-18.
Maeso, I, S. Roy, M. Irimia. 2012. “Widespread Recurrent Evolution of Genomic Features.” Genome Biology and Evolution 4:486-500.
Richards, T., J. Dacks, J. Jenkinson, C. Thornton, N. Talbot. 2006. “Evolution of filamentous plant pathogens: gene exchange across eukaryotic kingdoms.” Current Biology 16:1857-1864.
Richards, T., J. Dacks, S. Campbell, J. Blanchard, P. Foster, R. McLeod, C. Roberts. 2006. “Evolutionary origins of the eukaryotic shikimate pathway: gene fusions, horizontal gene transfer, and endosymbiotic replacements.” Eukaryotic Cell 5:1517-31.
Takishita, K., Y. Chikaraishi, M. Leger, E. Kim, A. Yabuki, N. Ohkouchi, A. Roger. 2012. “Lateral transfer of tetrahymanol-synthesizing genes has allowed multiple diverse eukaryote lineages to independently adapt to environments without oxygen.” Biology Direct 7:5.
Taylor, R. 2008. “Kangaroo genes close to humans,” Reuters, Canberra, Nov 18.
Wolf, Y., L. Aravind, N. Grishin, E. Koonin. 1999. “Evolution of aminoacyl-tRNA synthetases--analysis of unique domain architectures and phylogenetic trees reveals a complex history of horizontal gene transfer events.” Genome Research 9:689-710.
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