tag:blogger.com,1999:blog-3342041114052632712.post8794996491203432302..comments2024-01-20T16:39:42.179+11:00Comments on PhyloBotanist: Why are botanists more opposed to cladism than zoologists?Alex SLhttp://www.blogger.com/profile/00801894164903608204noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-3342041114052632712.post-27016490667284347952013-02-20T15:34:04.480+11:002013-02-20T15:34:04.480+11:00I am not saying there are no differences, but the ...I am not saying there are no differences, but the only group that has plausibly been argued to potentially lack phylogenetic structure are bacteria because they steal each others genes so often - the whole hyperbolic "Darwin was wrong" and "bush of life instead of tree of life" discussion from a short while back. (Not sure whether the same applies to Archaea...)<br /><br />It is also curious how this argument is supposed to proceed: according to certain colleagues, we should accept paraphyletic taxa because of hybridogenic speciation. But if there was, in plants, a net of life instead of a tree of life then there could be no paraphyletic taxa either. They cannot have it both ways. If there is a phylogeny, then whole branches of it are the only natural taxa. If there isn't a phylogeny, then there are no branches, so one cannot formally recognize partial branches either. In that case, all that remains is phenetics, no?<br /><br />Because commenters have so far been few and civilized, I have not made any restrictions on commenting. I assumed the Name/URL option under "comment as" would allow one to enter a name.Alex SLhttps://www.blogger.com/profile/00801894164903608204noreply@blogger.comtag:blogger.com,1999:blog-3342041114052632712.post-56035861766603170102013-02-20T13:52:58.346+11:002013-02-20T13:52:58.346+11:00When I first got seriously interested in plants, f...When I first got seriously interested in plants, first cacti and various succulents, then amaryllis,I expected to readily grasp botanical taxonomy. It turns out that plants are not just green animals which do not run away. Rather they pose a number of situations which I have never encountered in fish. I now think there are strong differences between plants and animals, and a corresponding difference in how botanists and zoologists think about their subjects. <br /><br />I'm posting as anonymous as I don't see exactly how to post by name. Jim Thomerson Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3342041114052632712.post-40122830422645817862013-02-20T09:28:17.651+11:002013-02-20T09:28:17.651+11:00The question is whether the hybridogenic species a...The question is whether the hybridogenic species are so many, so persistent (as opposed to high-level polyploidy usually being a dead end) and derived from parents so distant as to make species relationships too net-like for phylogenetic systematics to work. Looking at the reproductive boundaries across the plant kingdom, I strongly doubt that. Especially if hybridogenic speciation mostly happens between very closely related species, you just have to "zoom" out a bit and you have a tree-like structure again. And most of the controversy does not focus on classifying the species of, say, madly hybridizing Mentha section Mentha but on higher level relationships where hybridization is not an issue.<br /><br />25% also seems very high at least based on what I have seen so far. Is it possible that this number was advanced by people unaware that they would have to rule out incomplete lineage sorting as an alternative explanation for incongruent gene trees?<br /><br />Thanks for the info on ichtyology; I was completely unaware of that. Must admit that vertebrates never interested me as much as arthropods and molluscs.Alex SLhttps://www.blogger.com/profile/00801894164903608204noreply@blogger.comtag:blogger.com,1999:blog-3342041114052632712.post-38108006571635696492013-02-20T08:08:46.905+11:002013-02-20T08:08:46.905+11:00Just a hobby botanist at most. I have the idea th...Just a hobby botanist at most. I have the idea that a fair number of flowering plant species are of hybrid origin. I've seen different percentage numbers, up to, as I recall, some 25%. I have thought this one reason that botanists have been slow to accept cladistics. Cladistics, as I have understood it, does not deal well with hybrid origin groups, ie, non monophyletic.<br /><br />Ichthyologists, at least, are fairly uniform in using an -iformes ending for orders, and -idae for families, of course. In the groups that I follow, I think there has been an increase in families and orders, so we have not seen the consoldiation problem so much. Anonymousnoreply@blogger.com