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New at The Design of Life: Can hybrids create new species?

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Posted by Denyse O’Leary for Jane Harris

At one time, hybrids were thought to be common among plants but rare among animals. But as more animal hybrids are found, some scientists ask whether hybrids are not a more common means of creating new species than previously thought. …

An intense focus on Darwin’s theory that natural selection is the main cause of new species has often meant that other possibilities are neglected.

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Denyse, I will comment here rather than at Design of Life. Earlier this week I had planned on writing a detailed description of what I believe the evidence points to. Your post at Design of Life just reinforces my point of view. Namely, everyone who believes in ID should embrace the modern theory of evolution (MET) but in a limited way. It is good design and thus should be part of the ID scenario. To many here this is heretical but if we are truly endorsing science here then it makes good sense. I just rejected the naturalistic approach to evolution on another thread because there is no forensic evidence. But here I am going to endorse significant parts of the modern evolutionary theory because 1) I believe the forensic evidence is there and 2) it is great design. The modern theory of evolution explains downward evolution but not upward evolution. We first saw this in the Cambrian Explosion. In fact there may not be anything as upward evolution but that is still to be proven. There is definitely downward evolution and the mechanism for it MET. The gene pools contain a lot of possibilities that are not expressed and over time different morphologies will appear because of the three main elements that reshuffle the genes in members of a gene pool. They are natural selection, genetic drift and gene flow. Your hybrid examples are the result of gene flow. In all of this is the interaction of the environment. Over time the gene pool is able to create the families and genera and from these flow new species. The traditional Darwinian explanation is that the gene pool is constantly being expanded by mutations and over time these mutations create complexity and novelty in an upward fashion. There is absolutely zero evidence of any upward evolution as Behe's Edge of Evolution indicates. But there is loads of downward evolution. But what is completely reasonable and seems to be in sync with the data is that population gene pools may contract because of geographical separation and environmental conditions. There may be many other ecological changes that may also affect the gene pool of a population. Essentially reducing the gene pool with the occasional mutation adding to it in some trivial way. And when this happens we get the richness of life we see in the world but not by any upward creation of new species but a downward creation. We see different types of iguana, fruit flies, birds, fish, cattle, canines etc that are the result of geographic dispersion and environmental conditions. And the mechanism is natural selection, genetic drift and gene flow along with an occasional mutation that modifies but does not create any complexity or novelty. This is exactly what Darwin saw on the Beagle but he extrapolated the wrong way and that is why we are in the mess we are in today. As I said this process increases the richness of life which we see about us. Your hybrid examples just add to the evidence supporting this position It is folly to think that each species was created separately but that does not mean that everything has a purely naturalistic mechanism for its origin. The real debate is where did the gene pools come from because Darwinian processes are constantly winnowing them down. This system which enables populations to adapt is fantastic design and any designer would be proud of it. It allows for organisms to morph into slightly different variations over time to adapt to different environmental conditions and thus to prosper and avoid extinction. I would bet the actual design of the DNA and its reproductive mechanisms are what lets this happen but only to a limited degree (I understand transcription and translation and error checking but the system is designed to allow some modification but not a lot.). And the whole is an amazingly interrelated system that lets this limited adaptation take place but does not let it get out of hand. This has been a little bit rambling and when I have time will try to put it in a more organized fashion. But if anyone has any suggestions for improvements, criticisms etc. I would appreciate it. jerry

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