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There’s no such thing as a tree (phylogenetically)

eukaryotewritesblog.com

11–20 of 137 posts

Re: There’s no such thing as a tree (phylogenetically)

#12
post #11

A fern is not a tree. Hmm... What about a Tree Fern?

> “woody plants”, like lianas (thick woody vines)

There are plants that start out as parasitic vines (parasitic? Epithetic? I am not sure what words to use...) that grow, as a vine, up a tree. Kill the tree, then stand as a tree from then on.

https://live.staticflickr.com/5066/5645437671_f04c556157_b.j...

Re: There’s no such thing as a tree (phylogenetically)

#13
Well, I thought this was a fascinating and well-written article.

p.s. I learnt not long ago that there's no such 'thing' as an antelope:

"The term antelope is used to refer to many species of even-toed ruminant that are indigenous to various regions in Africa and Eurasia. Antelope comprise a wastebasket taxon (miscellaneous group) within the family Bovidae, encompassing all Old World ruminants that are not bovines, caprines, deer, or giraffes."

https://en.wikipedia.org/wiki/Antelope

Re: There’s no such thing as a tree (phylogenetically)

#15
post #6

I’ve become increasingly interested in what I think would be called “computational botany” if it were to be fleshed out. In looking at this and articles like it, and speaking with both trained and amateur botanists, a common thread is that the appearance of a plant has become increasingly detached from its scientific classification. A frequent refrain in nature hikes I’ve been a part of goes along the lines of: “this…

The phylogenetic tree of life is organized not on the characteristics, but on the evolutionary origin of species. Species are in a specific branch of that tree if they share a common ancestor species with the whole branch. Shared characteristica were a good proxy for ancestry back when the mechanism behind inheritance of genes was not discovered yet. Of course, the concept of a species is a bit fuzzy (even the possibility of genetic compatibility for reproduction as a criteria has issues), but over long timescales the relationships should align into a tree.

A big underlying assumption of this is that genetic material is only passed from progenitors to offspring. Specifically, horizontal gene transfer (common for bacteria, viruses and possibly others, but believed to be very rare for multicelled organisms) throws a huge spanner into efforts to derive phylogenetic trees. It can still be useful though under the assumption that not all genes are eligible for being transferred horizontally.

Also organizing programming languages into a phylogenetic tree is doomed to failure because in general it's quite easy to transfer features from one language to another, and back, as languages are not picky about incorporating features from offspring languages.

Re: There’s no such thing as a tree (phylogenetically)

#17
> Imagine if actually there were amphibian birds and mammal birds and insect birds flying all around

Bats (mammal)

Mosquitoes (amphibian)

Any number of flying insects. My least favourite is a two inch long flying cockroach that I encountered on a visit to Tāmaki Makaurau

Re: There’s no such thing as a tree (phylogenetically)

#18
post #9

I don't get the premise of the article. A tree is just a growth shape of a plant (plants are quite flexible regarding growth shapes, and often adapt to the environment), and a category that our minds place a plant species into. And its clearly an ancient ability common to all vascular plants to develop woody tissues. So why would we expect the tendency of a plant to become a tree to depend on its position in the phyl…

Intuition and vernacular make poor guides to the formal lexicon of taxonomy, as I learned over the course of trying to answer the question "okay, so what kind of wasp am I looking at right now, anyway?" Two years, a couple shelf-feet of research material, and a great deal of dedicated study later - "dedicated" here meaning for example that I taught myself how to bind books because they're better for annotation and reference than PDFs - I find myself more or less able to give a fairly confident answer to that question in about two-thirds of cases, and even at that I'm often not very sure. And that's all just been to develop an experienced birder's sense of where a given animal fits into the broader picture! It'd be a lot more complicated if I were more than just a casual amateur.

Phylogenetically, it's likewise reasonable to say that there's no such thing as a wasp, as the category is paraphyletic in "all of Apocrita that isn't ants and bees". This doesn't render "wasp" meaningless in its vernacular sense, of course - I may know I just saw a female Auplopus architectus metallicus [1], but if you ask about her, I'll spare you the detail and just say she's a spider wasp whose babies are lucky to have a mom who's busy seeing they'll grow up big and strong like her. The point of the article isn't to discuss the vernacular, and the point of "there's no such thing as a tree" is to make a startlingly counterintuitive assertion that draws the reader into a detailed discussion of how genomic taxonomy works. Such statements constitute a fairly common rhetorical technique - one worth knowing about, so as not perhaps again to miss the forest for a single tree.

[1] https://aaron-m.com/2021/01/23/auplopus-architectus-metallic...

Re: There’s no such thing as a tree (phylogenetically)

#19
post #17

> Imagine if actually there were amphibian birds and mammal birds and insect birds flying all around Bats (mammal) Mosquitoes (amphibian) Any number of flying insects. My least favourite is a two inch long flying cockroach that I encountered on a visit to Tāmaki Makaurau

The paragraph continues

> ...and they all looked pretty much the same – feathers, beaks, little claw feet, the lot. You had to be a real bird expert to be able to tell an insect bird from a mammal bird

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