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

eukaryotewritesblog.com

31–40 of 137 posts

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

#31
post #2

When you think about it, it would actually be crazier if our common words matched exactly with biological evolution.

This is one of the cool things about math, there are a lot of aspects of math which stem from thinking, "well what if I took a square root of negative one?" or "what if geometry worked this way?" and then someone does the thought exercise and fleshes it out into something interesting. And then there just happen to be aspects of reality that end up being very nicely described by these what if questions

Historically the square root of negative one arose more naturally than you might think; it is basically impossible to avoid it when you derive a cubic formula. Historically the work on complex numbers started as soon as cubic and quartic formulas were derived, because complex numbers emerge naturally and unavoidably from those formulas (even for polynomials that have only real roots). At first mathematicians were generally dismissive of the imaginary units and viewed them as "nonsense" terms that sometimes appear in some formulas and there was a lot of doubt about dealing with such terms (the same doubt you might have if someone divided by zero while solving some formula, even if they wind up finding the correct answer). Those doubts were completely eliminated by the proof of the fundamental theorem of algebra.

For what it's worth, you can avoid "imaginary" numbers entirely if you want -- you can do arithmetic on real polynomials modulo x^2+1, or equivalently on 2x2 real matrices of a special form.

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

#32
post #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 possib…

> The phylogenetic tree of life is organized not on the characteristics, but on the evolutionary origin of species.

My mother's old university biology textbook presents this as one of a few "equally valid" visions for how taxonomy should be organized.

I agree with the modern view that it's the only valid vision, but it's interesting to see it presented in a "teach the controversy" way, and we can see from the comments above that other views have their defenders today.

However obvious gross physical characteristics may appear, evolutionary closeness is much more informative as to most questions. It tells you when things tend to be the same by default, as opposed to being the same due to similar environmental constraints.

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

#34

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, c…

The term for these sorts of categories is called "Wastebin Taxon"

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

#35
post #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...

Epiphytic. They are freeloaders instead of parasites.

Although there is some though that for instance moss high up in some very tall trees helps them overcome their hydraulic limitations by allowing them to absorb some water from their limbs instead of just the roots.

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

#36

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, c…

The term for these sorts of categories is called "Wastebin Taxon"

That's pretty much a worse than pointless comment, isn't it, without some reason/justification supporting it. The wiki page for the term in question begins "Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon)", so it does seem there's no one correct term.

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

#37
post #21

" Tree is not a distinct clade" is the version of the title that isn't clickbait horseshit.

How many people know what clade means, though?

I had a pretty rigorous and extensive course of biology in high school, we spent a lot of time poring over various details, but the word clade never even fell. (Granted, that was 1992-1996, so things might have changed.)

I only met the expression cladistics and clade much later in some popsci literature.

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

#38

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, c…

What's the difference between a ruminant and an ungulate?

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

#39
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…

In addition to the sibling comments, I'd point out that the article is sort of an extended riff on the phrase, "There is no such thing as a fish," which was a sloppy QI paraphrase [0][1] of a principle elucidated by the 20th century paleontologist Stephen Jay Gould, and later became the title of QI's well-known podcast [2]. And of course, fish do exist, just not in the simplistic way that many of us were taught as ch…

Chairs are also brought up in philosophical debacles: http://steve-patterson.com/no-chairs-do-not-exist/

The point seems to be close to what you describe, but not entirely: "chair" is a human-made label, assigned to physical objects in the real world, but it's too abstract. Lots of objects resembling a chair or named "chair" exist, each with their own peculiarities, features, identity, but that's just humans going around, marking stuff with an invisible label maker.

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

#40

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, c…

What's the difference between a ruminant and an ungulate?

Grass eating Vs hooves.
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