Plant Birth Defects
Dean - Well put. However, the term nurture of defects to survival would support a "human" touch to the evolutionary theory. Breeding and interbreeding create new "breeds" and "cultivars" but not new species?!?
I look at what Masters wrote in 1869 in his Vegetable Teratology about birth defects in plants being carried forward if they survive. Remember that this was pre Watson & Crick and Franklin, so the method of chemical teratogenesis was not understood. If a defect survives that is not the result of recessive gene expression but rather through another forced mutation, does that mean it will express itself again in the offspring? Many articles state that taking offsets from variegated plants, for example, will result in plants that frequently revert back to the normal parent plant. So how would one tie these changes moving forward as an evolutionary step or leap into the morphological variation of the future plants. I think it is akin to birth defects in humans. Cleft palate does not always carry forward, so would cristate or monstrose forms follow the same rules?? It is a problem with cell division in one form or another.
Getting back to the original statement of plants being forced to change due to cultural practices, the visible expression we see may not really represent the true holotype or lectotype but may rather be a paratype? The plant being used as the holotype may have been the personal favorite of the original describer and one of a series of paratypes at the describer's disposal. I think this is where I get confused on the identification of the true species and its description. I have seen this arguement presented when trying to determine whether or not the California Tiger salamander was a simple subspecies or species. How many plants that we are basing our nomenclatural descriptions on have had DNA analysis conducted on them. The 200+ year old herbarium specimen used to set the stage moving forward would probably not hold up today under the same scrutiny of classification standards. Just because the name was used first, does this always make it the right name??? Isn't that why we have a lot of synonyms?
Open thoughts. BTW. The Masters book has been reprinted and is a great read. The original is quite rare and expensive and I sure wish the reprint had been available prior to me shelling out those bucks for the original. Think of all those sports and cultivars I could have purchased.
Cheers!
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