Convergent Evolution - Reasonable conclusion? or convenient excuse?

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When similar structures are detected in different clades darwinists rationalize it away as convergent evolution - instead of making the more reasonable conclusion that not all life fits into a neatly nested hierarchy of traits.

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The nested hierarchy is deduced by looking at lots of traits - looking at one will give odd results.The overall strength of the argument for a nested hierarchy is very high - that's why scientists don't overturn it in the face of examples of convergence. It's supported by a large number of statistically significant studies of relationships based on morphology and / or genetics.If the majority of traits indicated that life does not fit into a nested hierarchy - then we would have to throw away that concept. But that's not the case. So, it is reasonable to retain the nested hierarchy based on what we know.Changes are happening now to our understanding of convergence, as genetic data overturns some previous thinking based on morphology. The genetics gives a better picture of what is truly convergent. Features that are based on different genetics but look similar are clearly convergent - and there are examples of this.Here's a case where evolution of blue eyes in humans and lemurs is shown to have a different genetic basis.Blue eyes in lemurs and humans: same phenotype, different genetic mechanism - PubMedThis isn't always the case of course, but this kind of result does demonstrate that at least some convergence is only phenotypic.

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The overall evidence for a nested hierarchy is not high - the many cases of 'convergent evolution' demonstrate this

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Hi Bob,The nested hierarchy is evidenced by many things - genetics, morphology, the fossil record. Taking organisms as a whole, rather than just focussing on convergent features, it emerges clearly from the data. Recent genetic evidence (ERVs, retrotransposons, pseudogenes) has only made the case stronger.Convergent evolution is expected to occur. The question is - how much convergence would be a threat to the evolutionary view?My view is in line with WK - only genetic convergence is a potential threat to this view. And it only becomes a threat if the probability of these genetic convergences, taken as a whole, is very low, with the additional proviso that there is no natural mechanism of horizontal gene transfer to account for these convergences.So, how much convergence would be expected to occur under the evolutionary scenario? How much convergence is there? How unlikely is that to have occurred by chance? iIf there is an excess, what leads you to think there is no natural mechanism out there to account for it?If you can answer these questions, you will be on your way to building a case.