Crickets Convergently Evolve

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Crickets convergently evolve, as reported in BBC News, ScienceDaily and Nature News 29 May 2014, and Current Biology doi: 10.1016/j.cub.2014.04.053. Male crickets attract mates with a chirping sound made by scraping their wings together. The sound is produced when a series of grooves and ridges on their wings rub over one another. Unfortunately for crickets in Hawaii the sound also attracts deadly parasitic flies. In 2003 scientists found that male crickets on the island of Kauai had flat wings that would not produce any sound, thus making it harder for flies to find them. The scientists estimated that 95% of Kauai male crickets were chirpless, but were still able to find a mate by remaining close to any remaining noisy males.

Scientists have now also found silent crickets with flat wings on another Hawaiian island, Oahu. The two islands are too far apart for the crickets to have flown there by themselves, but did the insects hitchhike on boats and planes? Gene studies revealed the flat wings have been produced by different mutations, so the flat wings do not have a common chirpless ancestor.

The scientists who carried out the study claim this is an example of “rapid convergent evolution” where two different mutations occurred independently but produced the same result. They write in their report: “Divergent wing morphologies linked to different loci thus cause identical behavioural outcomes—silence—illustrating the power of selection to rapidly shape convergent adaptations from distinct genomic starting points”.

Nathan Bailey of St Andrews University commented: “There is more than one way to silence a cricket. Evolution by natural selection has produced similar adaptations from different genetic starting points in what appears to be the blink of an eye in evolutionary time”. He also told BBC News, “This is an exciting opportunity to detect genomic evolution in real time in a wild system, which has usually been quite a challenge, owing to the long timescales over which evolution acts”.

BBC, Nature News, ScienceDaily

Editorial Comment: The change from noisy grooved wings to silent flat wings is a change brought about by a degenerate mutation, and propagated by natural selection, but it is not evolution, convergent or otherwise. The flat wings have a selective advantage ONLY in the presence of parasitic flies and ONLY as long as there are some remaining CHIRPING crickets with normal wings. When either the flies or the chirping crickets disappear, so will the chirpless ones, because they won’t be able to attract mates.

The fact that there is more than one way to silence a cricket, merely proves there is more than one way for genes to degenerate, and is a good reminder of what mutations really do – they destroy genetic information. In this case they have destroyed the information for grooved wings. Here we see how the processes that supposedly drive evolution are really degenerative processes that eventually destroy living things. The real history of the world is from created perfection to degeneration. Change yes, evolution NO!

Finally, the term convergent evolution is often used to explain why creatures that live in similar environments have similar features, but this does not explain how they got these features. (Ref. insects, ecology, mutations, selection)

Evidence News vol. 14, No. 9
4 June 2014

Creation Research Australia