naming of plants

Robin Graham Bell
Wed, 06 Jan 2016 13:03:49 PST
Hi Ben, I don't have a problem with the binomial system or the attempt to systematize biology, we all need to have a name to discuss something. Nor do I want to write the long form reply. Of course taxonomists had nothing other than structure to work with originally & they did what they could, that's not really the problem. The problem is how this was all done, a series of measurements does not constitute an experiment or a proof, no matter whether you're measuring one or many characters. One can say two plants, populations or whatever, are different, using whatever measurements you want, but does that mean they are different species? How do you know, which should mean how do you prove it. At the moment it rests on someone's authority/respect/standing. Alternative explanations are virtually never considered.That is not science. I wonder how many species a taxonomist might have found with Mendel's peas?
	Given that everyone agrees ( I think) with the utility of the binomial system, it is pertinent to ask what is the definition of a species? Here is wikipedias...."a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding". That seems pretty good to me, although these days one might quibble with the idea of exchanging genes. "Capable" would seem to imply any interbreeding not only in the field. I would add one small extra, that is the offspring of such a cross should be interfertile, i.e. with parents & other F1. I'm sure that many would quibble with this definition, not least because its use would knock off at least half & maybe more like 90% of species out there right now.
	Why should one care? Well, there is a strong tendency in botany to treat the designation of a new species as the end of the road, it is catalogued, pigeonholed, a new monograph is written, superseding the previous one & that is the end of that. In my view this is a strong impediment to understanding anything. Or conducting any insightful biology. For example, I would like to know why plants need so many genes, humans, for example, have ~24.000 but at least some plants have well into the 40,0000 range. Even something as manifestly simple as Arabidopsis has more genes than humans, & Paris japonica has the largest known genome. I'm sure you know all this stuff, but answers as to why it should be, seem rare, even questions seem rare.
	Not only that, but questions about what might be rapidly evolving plants in any geographic area are submerged when they are all assigned species status, game over, we understand that lot.
	The DNA analysis & comparison seems more & more to be based on one or two genes, & not necessarily even the whole gene. Genome screening of a putative new species consists of finding a gene that is "informative" that is, conforms to ones expectations; just like looking for an anatomic difference in earlier times. We ignore & reduce the significance of all that is indistinguishable, even if this could be over 99% of structure.This is simply fishing for a confirmation of hypothesis, same as the old taxonomy, find a difference & you've got it, new species! It seems that the DNA work has successfully shown that taxonomy was often in error in the past, but at the other end it is simply becoming the "new" taxonomy.
	Finally, while you may not personally benefit from the discovery of a new species, people do benefit from these discoveries,  taxonomists get tenure, publishers get books, nurserymen get plants, often expensive ones, people underwrite discovery expeditions & gardeners want to have them & other people become experts. Although definitely modest & pretty harmless, species discovery would appear to have many of the hallmarks of an industry. Wild plants also suffer as folks go out & dig the new discoveries up to have or to sell. That's not a plus.
	I hope this clarifies my comments a bit.
	Robin Bell, Medford OR zone7/8
On Jan 6, 2016, at 12:37 AM, Ben Zonneveld wrote:

> ​I like to defend the taxonomists, although I am a genticist
> If properly done new taxa are based on many characters​.These can be
> divided in morphological characters, DNA sequence characters and what I do
> myself the amount of DNA per nucleus. I investigated all wild galanthus (
> and many other genera)in that respect. They vary in the amount of nuclear
> DNA from 49 to 164 pg DNA per nucleus. So it is easy to discriminate the
> Galanthus species (humans have about 7 picogram)Yes there are hybrids.
> These can be recognized because often also the parents are around. Moreover
> they are often sterile. Lastly naming new taxa is just part of the job, no
> extra money involved.
> Ben
> -- 
> BJM Zonneveld
> Naturalis, Herbarium section
> Postbox 9517
> Darwinweg 2,  2300RA Leiden
> The Netherlands
> Email: <>,
> telf 071-7517228
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