GCG-2017 Classification principles

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Notes from a discussion on day 1 of the meeting

Tony: we have a rare opportunity to recast the classification. You don't often get such an opportunity, and we should avail ourselves of it.

Eric: we can't wait until we know everything... we should take the opportunity we have now and do the best we can, without being afraid to place spp as unknown when we don't know enough yet. Having an informal clade structure can also help, even if it's not definable by morphological characters. We need the flexibility to define small sections if we need to, based on morphology and phylogeny, but aggregate them into larger groups based on informally named clades as we need to.

Julian: Focusing at the finest scales is fine: we need sections even if they are small. In some cases, small groups that seem screwy and morphologically cryptic can be diagnosed when we look more carefully. I bet that if you use your hand lens and a little work, you can figure out a taxonomy that works. The ideal situation is that you want taxa you can key out using a hand lens. Carex is a bit difficult because of the scale of the problem.

Eric: true, but using the informal clade names as a way of organizing the information allows people to dive into the clades and do some work on it. Everyone in the group can then work on the clades they feel most comfortable with. Don't think about the number of species as a principle, but rather what kind of morphological distinctiveness we want sections to have.

Julian: In fact, the old subgenera will still be useful for identification. The character of an inflorescence prophyll is still pretty handy for pulling out a set of species that you can key out more easily.

Tony: in terms of any procedural things, I'm not sure exactly how you thought things might work out, but you could farm things out to people for a preliminary sketch. No one knows them all, but there are groups that are strictly Asian, strictly North American, strictly S. American... if people sketch out these, the rest we could tackle in a different way. slowly you build up to things that are done, then focus in on what's a mess.

Marcia: I think from what Tony's saying, what we need to do is organize a sort of pipeline for how you go from phylogeny to classification. A goal for this week is to identify the sections that we know pretty well, then go through and make another list of those that individuals are working on or have better information about, and can put information in... everyone then has a homework assignment to work on. We could make a list of clades and sections that go into them (or are split amongst them).

Eric: There are going to be a lot of nomenclatural issues that come up with this. Pedro's found that there are a bunch of sectional names published in old European floras that have not been considred, and that need to be looked at b/f we can go forward... they may modify what our views are. If we can tie types to sections, we can figure out what names apply to what groups. The trick is digging out old names, figuring out what sp. would be the type, figuring out if they were validly published. There is both the matter of figuring out group limits, but also figuring out names. [Tony:] it's true: there is nothing easy about this. All you can do is keep digging. If a section is entirely North American, we probably have a good handle on it. European groups are harder, because often there are old floras, and the texts have to be scrutinized to see whether the names were published at the section level at all. [Eric:] communication amongst groups is essential. [Tony:] Informal names will not do the trick in the long run. [Eric and Pedro:] but we don't do it in one shot: informal names may be a good way of making a first stab.

Marcia: If we all identify ourselves as a taxon-level or area-level experts, or a nomenclatural expert, we can farm the work out more concretely. We need specific assignments.

Eric: one way to consider doing this is to split the phylogeny into some major groups, and have a group leader help organize those subgroups. If someone is not taking the lead on a group, nothing will happen with it. It doesn't mean that that person has to make all the decisions. But if someone agrees to push on Vignea or some major clade of core Carex, then we know that is more likely to keep the whole process moving forward.

Marcia: if we know that person X is the expert on a particularly problem, then the group can get help from the regional expert.

Julian: From my experience, there are people who say yes and do it, and there are people who say yes and take forever. I've seen this happen on floristic projects. Let's not let this get set in stone.

Eric: If we have a few broad-stroke organizational products, these give us the foundation to move forward. If we have that structure, if we've created it as a group (ideally published), then I think that allows the group to move forward.

Marcia: the other advantage of organizing ourselves is that we don't duplicate each other's labors. That's another advantage of making an organizational plan.

Dave: I think you're going along the right direction there: I like what Julian and Eric were saying at the beginning. Get a classification out there as quickly as you can, one that reflects what the broader audience wants, not just what the Carex groups wants. But I'm wondering what kind of support there is for the further work.

Eric: Santi has funding in Spain, and there is also funding for a project in Pakistan. Thus we have some existing new grants that will guide some of the future directions of this research group, but we've not talked about other next steps. Pedro has one in for S. America, and there is a PAK-US proposal in for collaborative research.

Dave: one other thought: after the last meeting, there was a conversation about names. If you do get sectional names figured out, you should get them into IPNI. There are a lot of names not in there. Also, the World Checklist should have sectional names in it.

Karen: As you probably know, I am deeply involved in sectional nomenclature... the idea that was mentioned before of informal clade names is very sensible. It doesn't cause a mess later: if you have an informal name, you don't have to clean it up later if it proves to be problematic. That's a lot of not very productive work. I'd hate to see us bogged down on the nomenclature.

Qasim: We need a simple story. The sections that are recognized by morphology and those that are recognized based on DNA data. Thus we can have a set of names that capture unclassified spp. We have sections, we have regional groups... [Julian] this works as long as sections are regional. [Eric:] having both a set of researchers who are interested in regional questions and a set interested in taxonomic questions is helpful. [Tony:] there are sections that straggle among regions, so that having experts at both levels is helpful.

Pedro: I don't think I've been wasting my time doing the sectional nomenclatural work to date... I think we can come up with the best classification of a large genus to date. [Eric:] I would go off of that and say that a lot of the names we go off of that are problematic are of European origin. Particularly for clades that are N. American, we know the nomenclature well. But if we have done due diligence in trying to find all the sectional names that apply... there's always a chance that someone might dig up an older name, but this shouldn't keep us from doing the best we can to propose names. It's okay to hold off where we think we need to, using informal names where it is most prudent to do so, but using formal names when we can. [Pedro:] this will help us to avoid causing more problems in the future.

Karen: again, I see no problem in having a mix of formal and informal names. There is also no problem with proposing to conserve a well used name, even when it doesn't have precedence. (I hesitate to mention this, as we're being inundated with requests to conserve names now.)

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