Recent Problems in Evolution - 2003

Table of Contents

Stick insects evolved and lost wings at least four times

Evolutionists have assumed that wings evolved only once in insects. Evolutionary theory states that once an evolutionary trait is lost, its genetic code will rapidly degenerate, since there is no longer selective pressure to prevent deleterious mutations to the gene(s) which encode the trait. A newly published study brings this idea into question, since it suggests that wings appeared and disappeared in phasmids (stick insects) at least four times. Since the study covered only 14 of the 19 known sub-families of phasmids, it is possible that wings reappeared even more times.

Evolutionists attempt to explain this unusual data through the turning off of the master control genes that direct the development of both wings and legs. However, the study failed to show that the development of wings was completely (or even partly) controlled by the same genes that control the development of legs. Until that is shown, the evolutionary explanation is pure speculation. The existence of even one gene that codes exclusively for any part of wing development or structure would invalidate the evolutionary explanation, since its destruction through random mutation would be virtually guaranteed during the millions of years between the appearance of the different species of phasmids.

Whiting, M.F., S. Bradler, and T. Maxwell. 2003. Loss and recovery of wings in stick insects Nature 421, 264–267.

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Vital function found for mammalian pseudogene

Pseudogenes are regions of non-coding DNA (DNA that does not code for functional protein) that have been apparently duplicated from functional genes. In an article on this site, I had speculated a couple years ago that pseudogenes might be involved in some kind of gene regulatory function. However, until last month, no function had been found for any pseudogene. But, in an extreme case of serendipity, investigators had inadvertently inserted their target gene into a mouse pseudogene. They wouldn't have known that they had done this except that 80% of the mice from that one line died of multi-organ failure. Instead of discarding the "bad" line of mice, the scientists investigated to find out why the mice had died. What they found was that the mouse pseudogene was regulating the expression of its corresponding functional gene. Not only did the pseudogene serve a function - it was required for the survival of the mice! Alas, the last the of the evolutionists' "junk" DNA has been shown to be functional.

Hirotsune, S., Yoshida, N., Chen, A., Garrett, L., Sugiyama, F., Takahashi, S., Yagami, K., Wynshaw-Boris, A., and Yoshiki, A. 2003. An expressed pseudogene regulates the messenger-RNA stability of its homologous coding gene. Nature 423:  91-96.

Lee, J. T. 2003. Molecular biology: Complicity of gene and pseudogene [News and Views] Nature 423: 26-28.

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Ancient human DNA shows humans did not evolve from Neandertals

A new study has examined the mtDNA sequences of two Cro-Magnon specimens dated to 23,000 and 25,000 years old. One specimen (Paglicci-25) had no sequence differences from the modern reference sequence, and the other (Paglicci-12) only one substitution. It is remarkable that so little change in the sequence had occurred over the last 23,000 years. The ancient Cro-Magnon mtDNA and modern European mtDNA differed by only 2-3 base pairs on average (see table below). This difference is even less than that observed among modern Europeans! In contrast, these ancient modern humans differed from nearly contemporary Neandertals by an average of 24 base pairs.

mtDNA Sequence Variation Among Modern and Ancient Hominids
Individual Modern Europeans Neandertals
Mean Min. Max. s.d. Mean Min. Max. s.d.
Paglicci-25 2.3 0 11 1.8 24.5 23 28 2.4
Paglicci-12 3.2 0 10 1.7 23.5 22 27 2.4
Modern Europeans 4.4 0 18 2.3 - - - -

According to the authors of the study:

"Although only six HVRI sequences of ancient a.m.h [anatomically modern humans] and four sequences of Neandertals are available to date, the sharp differentiation among them represents a problem for any model regarding the transition from archaic to modern humans as a process taking place within a single evolving human lineage."

Caramelli, D., C. Lalueza-Fox, C. Vernesi, M. Lari, A. Casoli, F. Mallegnii, B. Chiarelli, I. Dupanloup, J. Bertranpetit, G. Barbujani, and G. Bertorelle. 2003. Evidence for a genetic discontinuity between Neandertals and 24,000-year-old anatomically modern Europeans. Proceedings of the National Academy of Science USA 100: 6593-6597.

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Mammalian Conserved Non-Genic Sequences (CNGs)

A study of 191 non-coding sequences of human chromosome 21 revealed that they were more identical among 14 mammalian species than DNA that codes for proteins. The data suggested that these regions serve some vital function among diverse mammalian species. The study indicates yet another function for "junk" DNA.

Dermitzakis, E. T., A. Reymond, N. Scamuffa, C. Ucla, E. Kirkness, C. Rossier, and S. E. Antonarakis. 2003. Evolutionary Discrimination of Mammalian Conserved Non-Genic Sequences (CNGs) Science 302: 1033-1035.

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Last Modified May 11, 2004