[HN Gopher] There's no such thing as a tree, phylogenetically
___________________________________________________________________
There's no such thing as a tree, phylogenetically
Author : rbanffy
Score : 232 points
Date : 2021-05-09 08:54 UTC (14 hours ago)
(HTM) web link (eukaryotewritesblog.com)
(TXT) w3m dump (eukaryotewritesblog.com)
| DangitBobby wrote:
| For so many species to have indepently developed wood, it must be
| a highly beneficial (or, at least, not detrimental) adaptation
| that is relatively easy for plants to mutate. I would not expect
| a more complicated fundamental structure (an eye, for example) to
| have developed indepedently numerous times, but something a bit
| simpler like wood is not terribly surprising.
|
| I am expecting responses to the tune of "eyes are not that
| complicated" and "wood is actually incredibly complex."
|
| Do all creatures with a brain share a common ancestor? Even more
| fundamentally, do all creatures share a common ancestor? The
| answer appears to be "maybe," which I find to be fascinating [1].
|
| 1.https://www.researchgate.net/publication/44593277_A_formal_t...
| Scene_Cast2 wrote:
| The eye _has_ been developed twice - check out cephalopod eyes.
| If anything, their design is superior (no blind spot, nerves on
| the rear vs front, hard lens vs soft deformable lens for
| focusing)
| DangitBobby wrote:
| That's interesting. The Wikipedia entry [1] mentions that
| there's still debate about whether it's parallel evolution
| [2] or convergent evolution [3].
|
| I'm very curious about why this comment got downvoted.
|
| 1.https://en.m.wikipedia.org/wiki/Cephalopod_eye
|
| 2.https://en.m.wikipedia.org/wiki/Parallel_evolution >
| Parallel evolution is the similar development of a trait in
| distinct species that are not closely related, but share a
| similar original trait in response to similar evolutionary
| pressure.
|
| 3. https://en.m.wikipedia.org/wiki/Convergent_evolution >
| Convergent evolution is the independent evolution of similar
| features in species of different periods or epochs in time.
| carapace wrote:
| I've been looking into plants recently and they are mind-blowing.
|
| I don't even know where to start.
|
| In re: TFA, most annuals that we use for crops have perennial
| versions. I just planted a "thicket bean" (Phaseolus
| polystachios) which should grow for years! There are perennial
| kales that grow into small tree-like "canes". There's a thing
| called a "strawberry tree" that is exactly what it sounds like: a
| tree that grows strawberry-like fruit. It goes on and on.
|
| One take-away is that agriculture as it has been practiced is
| about the dumbest way to grow food. :( Check out Gabe Brown's
| videos on regenerative agriculture to see how we can grow food
| and increase fertility and volume of soil by incorporating more
| species and doing less work. See also the "food forest" concept:
| imagine a park or botanical garden where every species is edible.
| It takes a while to set up but then it is self-sustaining with
| low labor, you mostly just harvest.
|
| Another take-away is that we mostly already have all the
| technology we need to make a really fun and enjoyable
| civilization. We have all these species that can develop food,
| medicine, clothing, fiber, wood, etc. such that the vast majority
| of our needs can be fulfilled in a garden.
| moralestapia wrote:
| I know about regenerative agro and I find it amazing as well.
|
| I just want to point out that the way modern agriculture came
| to be is not dumb at all, the thing is that its focused on
| maximizing yield above other things. 7 billion people eat
| something (almost) everyday, I find it quite impressive that
| the infrastructure to support that, exists.
|
| I hope the world could be stopped (as it happened, more or
| less, with COVID) in order to fix some of these problems, but
| in the case of food, it's going to be hard to ask people to
| stop eating for a while.
| admash wrote:
| Just an aside - I have the perennial walking-stick kale growing
| at my place. I climb on my roof to to harvest it. It grows
| enormous leaves too.
| theli0nheart wrote:
| > _There 's a thing called a "strawberry tree" that is exactly
| what it sounds like: a tree that grows strawberry-like fruit.
| It goes on and on._
|
| Cool reference that I hadn't heard of before, so I just looked
| this up. The fruits of this tree look absolutely nothing like
| strawberries (more like lychees, IMHO), so I don't think this
| is a good example for what you're describing.
| mlinksva wrote:
| They're very common in the bay area as street trees. The
| fruits are decent, but indeed don't look or taste anything
| like strawberries.
| https://en.wikipedia.org/wiki/Arbutus_unedo
| freshair wrote:
| They look very similar (though probably larger) to mock
| strawberries (which are not really strawberries either.)
|
| https://en.wikipedia.org/wiki/Potentilla_indica
|
| Incidentally: from a botanical perspective, strawberries are
| not berries. Nor do they even taste like straw!
| silviot wrote:
| I'm not sure it's connected to the origin of the word, but
| when I saw straw laid down in strawberry fields like this
| [1] I thought the name comes from that custom. I believe
| (still, I could be wrong) that the straw is put there to
| prevent weeds from getting sunlight.
|
| [1] https://i0.wp.com/oaeblog.com/wp-
| content/uploads/2018/06/Ger...
| ncmncm wrote:
| Botanically, practically nothing _we_ call a berry is a
| berry except blue-. And practically every other fruit _is_
| a berry. The word is a wastebasket.
|
| Today I learned that papaya is closely related to cabbage.
| ncmncm wrote:
| Speaking of which, the Raspberry Jam Tree, also called Jam
| Wattle, of western Australia, does not grow raspberry jam,
| but smells like it when cut with a saw.
|
| No plant nursery will sell you a Raspberry Jam Tree, but you
| can buy seeds on Etsy: "Acacia acuminata".
|
| They are interesting also because the leaves (which aren't
| leaves, but "phyllodes") and bark have a high concentration
| of interesting tryptamine alkaloids.
|
| There are many other fascinating details about A. acuminata.
| Millions of fenceposts in Australia more than a century old
| (and more every year!) are made of its wood.
| stjohnswarts wrote:
| If they taste like strawberries is all that would matter to
| me. Then again I'm one of those people that will often mix
| what's on the plate and don't really care a whit about
| "presentation" when it comes to food. My gf hates me for
| that. Growing up poor in the south will often lead to
| inclinations such as that.
| amelius wrote:
| Tomatoes with some added sugar also taste like
| strawberries.
| ajuc wrote:
| > how we can grow food and increase fertility and volume of
| soil by incorporating more species and doing less work
|
| It still loses in profit per investment to modern
| industrialized farming, so (almost) nobody cares. If you want
| people to care - tax soil degradation.
|
| Turns out with artificial fertilizers and modern technology
| neither work nor soil degradation is as important as quick
| adaptation to market forces and economies of scale.
| nyokodo wrote:
| > agriculture as it has been practiced is about the dumbest way
| to grow food
|
| > imagine a park or botanical garden where every species is
| edible.
|
| Make it happen! If the way we've been doing things is dumb then
| there is a massive market opportunity. Save the world, become
| the first trillionaire.
| carapace wrote:
| Gabe Brown makes money. His neighbor ignores him. What can
| you do?
|
| It does seem like folks are catching on though. Business can
| be slow to adapt, especially in agriculture, but farmers are
| pragmatic. Brown's talks seem well-attended.
| mistrial9 wrote:
| control is more important than technique, in most cases,
| and then winners reinforce that
| gus_massa wrote:
| > [...] _most annuals that we use for crops have perennial
| versions._ [...]
|
| > _One take-away is that agriculture as it has been practiced
| is about the dumbest way to grow food._ [...]
|
| One very useful technique in modern agriculture is crop
| rotation. https://en.wikipedia.org/wiki/Crop_rotation
|
| You grow each year a different crops, because they have
| different fertilizer requirements (and some even fix Nitrogen)
| and also helps to reduce some plagues. It's also possible to
| plant different crops in succession, so you get multiple
| harvests in the same year.
|
| For these, a perennial version is bad.
| Fellshard wrote:
| I suspect there's trade-offs that aren't being thoroughly
| considered in this equation. That's the case in every full-on
| 'everything we're doing is wrong, and there's a perfect
| solution' claim.
| oceanplexian wrote:
| The difference is between hobbyist agriculture and commercial
| agriculture. In the latter, consistency, pests and disease
| become more complex issues to deal with. IMHO there are a lot
| of analogies to software engineering. Small projects can
| engage in practices that don't scale, like skipping QA, not
| adequately testing, inconsistent coding standards.
|
| In large farms, seeds are mass produced, engineered, and go
| through a QA and testing process to prevent certain diseases.
| There are many good reasons, BTW, why farms don't grow
| perennials and engage in mono-cropping, or use herbicides and
| genetically engineered crops instead of no-till. The trade-
| off in abandoning these practices almost always involves
| sacrificing yields and the mechanization of labor.
| derefr wrote:
| Orchards of fruit/nut trees are both commercial
| agriculture, and centered around perennials. Are industrial
| orchards less productive than industrial farms?
|
| Or how about vineyards?
| skj wrote:
| The limit there is likely that no one has figured out how
| to make an annual fruit or nut tree.
| tbihl wrote:
| Thinking about the cost per calorie of apples versus
| oats, to pick an example that works for me, I would say
| the answer is very much yes. And ultimately, from the
| plant's perspective productivity should be a question of
| efficiently storing energy.
| [deleted]
| carapace wrote:
| Nope, in this case it's just science. Specifically _ecology_.
|
| It turns out that when we understand what the plants and
| animals are doing in detail (through science) we can arrange
| them in time and space in ways that are _vastly_ more
| efficient than what we 've been doing these last ~12k years.
|
| Think about it, if it wasn't so that would mean that our
| ancestors discovered _optimal_ farming in antiquity, eh?
|
| Just think: we used to burn chaff rather than composting it.
| It turns out that that is not a good idea. It's that sort of
| thing that I'm thinking of when I call ag "the dumbest way"
| to grow food.
| Aardwolf wrote:
| > Think about it, if it wasn't so that would mean that our
| ancestors discovered optimal farming in antiquity, eh?
|
| Farming has undergone several fundamental changes
| throughout history after that though, notably in medieval
| times and then everything industrialization brought
| tremon wrote:
| _Farming has undergone several fundamental changes_
|
| Can you name some that can't be reduced to "but on a
| [insert new machine]"? The only one I can think of is
| artificial fertilizer, which isn't a sustainable practice
| in the long run either.
| saalweachter wrote:
| US Corn Grain Yield Trends Since 1866: https://www.agry.p
| urdue.edu/ext/corn/news/timeless/images/US...
|
| It may take years for new practices to be widespread and
| accepted, but I assure you, if you can make that chart
| continue to go up, ~every grain farmer in the US will
| happily be on board.
|
| There is a certain world-view and a romanticizing to
| farming, but at the end of the day, farmers are
| businessmen who just want to grow as much food as
| possible, as cheaply as possible. They may grumble as
| much as a software developer when forced to learn new
| tools, and they won't drop everything for an unproven
| promise, but they'll happily abandon their old ways in
| favor of new ones once they're proven.
| ajuc wrote:
| Bosh-Haber process increased food supply several times in
| less than a decade. There was no starvation in a
| developed country ever since it got adopted on mass
| scale. It happened less than 100 years ago.
|
| Compared to that every other revolution in farming was
| insignificant.
| mistrial9 wrote:
| https://en.wikipedia.org/wiki/Haber_process
| ravi-delia wrote:
| Crop rotation replacing leaving fields fallow was a huge
| leap, as was the first really heavily selected strain of
| wheat.
| bch wrote:
| > It turns out that when we understand what the plants and
| animals are doing in detail (through science) we can
| arrange them in time and space in ways that are vastly more
| efficient than what we've been doing these last ~12k years.
|
| This assumes both systems are optimizing for the same
| thing.
| JulianMorrison wrote:
| A better way to phrase this is, when various plants with
| different evolutionary histories grow big, they converge on tree-
| like forms.
| narush wrote:
| The first line of this essay talks about fish not existing
| either. For anyone interested in this subject (albeit from a
| different angle) I highly recommend the book "Why Fish Don't
| Exist" [1].
|
| It's only really a little bit about fish, the founding president
| of Stanford (who was an obsessive ichthyologist), and his
| eugenics agenda. It's also part memoir. I found it very touching
| and quite good 4 the ole empathy.
|
| [1] https://www.simonandschuster.com/books/Why-Fish-Dont-
| Exist/L...
| msrenee wrote:
| I prefer to look at it from the other angle, which is that all
| vertebrates are fish. I had a professor who was mainly an
| ichthyologist, but overall a really old school natural
| historian. He always said that we were all just highly derived
| fishes. If you spend any time at all looking at evolutionary
| biology, it really does hold true. Bones in our heads can be
| traced back to the gill arches in bony fish. The pelvic girdle
| and shoulder bones developed from the pelvic girdle and
| pectoral bones of early fish. We're really just fish adapted to
| land.
| lupire wrote:
| Also, "There's No Such Thing As a Fish", the QI Elves trivia
| podcast.
|
| https://en.m.wikipedia.org/wiki/No_Such_Thing_as_a_Fish
| goldenkey wrote:
| QI is a gem of a television show. American has no such
| caliber of broadcast media.
| Blikkentrekker wrote:
| Why would this be surprising when the definition of tree is so:
|
| > _First, what is a tree? It's a big long-lived self-supporting
| plant with leaves and wood._
|
| I have some vines that are clearly capable of wood formation and
| sometimes seem to do so at places for reasons I can't understand.
|
| "tree" is clearly a horizontal classification; it is as
| surprising as as that not all animals that can fly have common
| ancestors that can.
|
| > _You know birds? Imagine if actually there were amphibian birds
| and mammal birds and insect birds flying all around, 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. Also, most people don't know that
| there isn't just one kind of "bird". That's what's going on with
| trees._
|
| I do not find trees looking similar at all.
| codegladiator wrote:
| > I do not find trees looking similar at all.
|
| What trees are you talking about ? or you mean in general ?
| Blikkentrekker wrote:
| In general.
|
| In particular, many trees grow from a central strem that is
| nearly perfectly vertical, and many have a more organic
| growth pattern. I see no reason to assume these have common
| ancestors that were trees any more than crabs and jellyfish.
| JoBrad wrote:
| I think you should read the article in a bit more depth,
| including the Twitter thread linked at the bottom.
|
| Some examples where your description doesn't hold up so
| well
|
| - palm trees
|
| - bamboo
|
| - fringe tree (Chionanthus virginicus)
|
| - Hydrangea paniculata
|
| - sunflowers
|
| - crape myrtles can have so many variations that it's crazy
| SideburnsOfDoom wrote:
| I once cut down a banana tree, with a breadknife.
|
| It's not very much like e.g. an oak tree. More like a
| scaled-up celery.
| samatman wrote:
| Bamboo is only considered a tree by people who don't live
| around any, and don't know any better.
|
| It is pretty obviously an enormous grass. Woody? Yes.
| Tree? No.
| BariumBlue wrote:
| > I do not find trees looking similar at all.
|
| When folks say "forest", like "I'm going to go hiking in the
| forest", they usually don't specify what species or genus of
| tree. A street could be lined with "trees", or a "tree" could
| fall on someone's car. We categorize trees together because
| they tend to occupy the same enough overall role and profile.
|
| Now if there was a "baobob tree" forest, or a "palm tree" fell
| on a car, those are distinct to merit specification.
| swiley wrote:
| I'm pretty sure I've heard people talk about the kinds of
| trees in forests like that before.
|
| I've certainly heard people mention the kinds of trees when
| talking about small stands of trees (ex: "this stand of pines
| over here.")
| Blikkentrekker wrote:
| > _When folks say "forest", like "I'm going to go hiking in
| the forest", they usually don't specify what species or genus
| of tree. A street could be lined with "trees", or a "tree"
| could fall on someone's car. We categorize trees together
| because they tend to occupy the same enough overall role and
| profile._
|
| That sounds like something that could very much be different
| in different languages.
| dragonwriter wrote:
| > When folks say "forest", like "I'm going to go hiking in
| the forest", they usually don't specify what species or genus
| of tree.
|
| well, no, because there aren't usually multiple forests that
| could be meant that would be disambiguated to a single forest
| (warranting the definite article) by genus of trees, there is
| either one candidate (requiring no qualification) or multiple
| but needing some other qualification (like specific name of
| the forest or direction from the current location.)
| intuitionist wrote:
| I disagree. Within walking distance of my suburban (Eastern
| US) home, there's a patch of woods that's mostly oaks and
| maples, a larger patch that's oak-hickory, and a large park
| that's primarily beech-maple. Out West, you could walk
| among redwoods, or bishop pine, or coast live oak or
| tanoak.
| GavinMcG wrote:
| Do you call certain tall woody growths something else, then?
|
| The birds bit is an analogy. It's not about looking identical,
| it's about looks (tall woody thing) and shared name (tree) not
| corresponding to phylogenetics.
| bsaul wrote:
| it is so strange how things evolve in parallel in various fields.
| We used to love object oriented modeling with inheritance
| hierarchies, until the point we realized how it was so hard to
| have any hierarchy perfectly match a given domain.
|
| Then we moved to composability + interface, realizing it's easier
| to compose attributes (often related to a given set of functions)
| to make any graph of structures instead of just a tree.
|
| Just two days ago looking at how virus recombined themselves in
| the most random ways, i wondered if the species classification of
| the previous centuries based on trees were not destined to follow
| the same path.
| Blikkentrekker wrote:
| In this case "parallel" is:
|
| > _First, what is a tree? It's a big long-lived self-supporting
| plant with leaves and wood._
|
| That is such a broad thing that it's hardly remarkable. I find
| carcinization, or independent evolution of eyeballs from
| completely different tissues to be more remarkable.
|
| This is no more remarkable than that animals independently
| evolved to be large, and in doing so evolved different hard
| support structures to support this, which for instance worms
| lack.
| archibaldJ wrote:
| There are something very interesting about structures and costs
| here. Perhaps two types of costs, cost-to-execute and
| (meta-)cost-to-transform. In general one can argue that
| hierarchy optimises for cost-to-execute while composition
| optimises for cost-to-transform.
|
| Maybe in some way most things can be viewed from the lense of a
| compiler/interpreter. "Structures" are really just existing
| meta-cache for how to efficiently traverse the language to
| enforce semantics that result in computations.
|
| e.g. tail call optimizations are basically structures in the
| compilers that help to traverse a subset of the language (i.e.
| tail recursion) more efficiently time-and-space-wise
| thelastinuit wrote:
| I'm tripping and metatripping on this... do you have
| literature among those lines? Love to read about it more.
| archibaldJ wrote:
| A few that came to mind
|
| - The Tao of programming by Geoffrey James:
| https://www.mit.edu/~xela/tao.html
|
| - An Analytical Approach to Programs as Data Objects by
| Olivier Danvy https://cs.au.dk/~danvy/DSc/00_dissertation-
| for-printing.pdf
|
| - Maps of Meaning: Gautama Buddha, Adam and Eve by Jordan B
| Peterson - https://www.youtube.com/watch?v=F7T5cg1a77A
|
| - Theories of Programming Languages by John C. Reynolds
| https://www.amazon.com/Theories-Programming-Languages-
| John-R...
| beaconstudios wrote:
| When multiple disparate states evolve towards the same end,
| you're probably looking at what's known as an attractor - a
| state in state-space that is a stable local maxima. If
| evolution is an algorithm that optimises environmental fitness
| then some combinations of traits will just be really good at
| survival and reproduction and species with nearby traits will
| often evolve towards that specific set of traits.
| slver wrote:
| > We used to love object oriented modeling with inheritance
| hierarchies, until the point we realized how it was so hard to
| have any hierarchy perfectly match a given domain.
|
| You're describing a (for the lack of a better term) "fad
| cycle". Our industry, like all, goes through cycles where a
| given practice is declares holy and sacrosanct, doctrine
| evolves around it, eventually flaws in the idealistic view
| appear and because the entire foundation before was "this is
| flawless and essential" and turns out it's not flawless and
| essential, the practice is wholly rejected. It's swinging to
| extremes. Neither of which is useful.
|
| Experienced developers neither considered inheritance crucial
| property of OOP, nor they avoid it completely now.
|
| Inheritance is static decoration. Decoration is a form of
| composition. It's all forms of the same thing, where you can
| make some choices AOT and some choices JIT and you pay for AOT
| vs JIT in terms of ending up with a different
| performance/flexibility balance.
| bsaul wrote:
| there definitely a fad cycle , however i think it's also due
| to the fact that when exploring a problem we often try the
| simple approach first, up until we reach the limits of that
| approach, then move to a more complete one.
|
| I don't think we'll ever get back to modelling purely with
| strict trees of concepts, because this is simply not how
| things are in the real world.
| slver wrote:
| We never did model strictly with trees IMHO. The closest
| I've seen is probably OOP widgets, but there it makes sense
| (and yes I've seen stupid stuff in those libraries, but in
| general they make sense).
| [deleted]
| f6v wrote:
| In my phylogenetics course I learned that "rooting" a tree can be
| rather arbitrary. What you get is not a hierarchical structure,
| but rather links between different species.
| ufo wrote:
| Nevertheless, an unrooted tree is still a tree, in the graph
| sense of the word. (Not that this matters for the article
| though; they're talking about botanical trees)
| JoBrad wrote:
| As I recall, this is due to the difference between plant cell
| walls and animal cell walls. Trees, in particular, assume that
| if it's inside them, it's mostly legitimate.
| ncmncm wrote:
| Author might be disappointed to learn that the island of Lanai is
| not mostly covered by an orchard.
|
| Pineapples do not, by anybody's definition, grow on trees.
| mordymoop wrote:
| I've been watching a lot of bonsai YouTubers lately. The amazing
| thing about trees is how much abuse they will tolerate and still
| figure out some way to grow. You can find videos of somebody
| pruning all the leaf-bearing branches and half the roots off of a
| bonsai like it's nothing, fully expecting the tree to recover.
| Plants have a very flexible instruction set, something like a
| list of inner if-statements, which bonsai artists understand
| almost completely and use to dictate their growth. It seems like
| the default execution of this instruction set looks like "tree"
| when there are no particular challenges, but the plant would
| adapt to almost any trauma short of cutting it down to a 1ft high
| stump... and even then, you will find stumps growing branches.
| colechristensen wrote:
| There is an old method of forest management which I can't
| immediately remember the name of which does exactly this, cut
| down trees to their stumps and let the new growth build up for
| a number of years and repeat.
| papercrane wrote:
| Sounds like you're talking about coppicing. Some tree
| varieties will continue to produce young shoots from the
| stump, and those can be left to grow and harvested.
| Balgair wrote:
| On the Pacific Coast you can see this in action with
| redwood 'fairy rings'. The old redwoods got chopped down
| and then the roots sent up shoots in a ring about the
| stump. It all grows into pretty big ring of trees.
|
| Great for making forts in as a kid.
|
| Tall, hard woods. Great smells of the dank forest floor and
| the tannins of the redwoods. Birds twittering, squirrels
| barking.
|
| Dust, duff.
|
| Your imagination running buckwild about ancient castles or
| being an ewok. Mom calls at dusk for dinner, red spaghetti
| and bugjuice.
|
| Coolness creeps in and the scrubjays squawk at another.
|
| Just dark enough for flashlight tag.
|
| And running through church columns in twilight and you
| never get tired and you never get old.
|
| And everything is perfect.
|
| https://www.google.com/search?q=redwood+fairy+ring&source=l
| n...
|
| https://robertogreco.tumblr.com/post/10973003737/idrawninte
| n...
| msrenee wrote:
| It's called pollarding.
|
| There's also quite a few trees that can be a pain if you want
| them gone. You can cut them down to stumps and they'll just
| send suckers up and try to grow again. My dad has been having
| it out with a lilac bush since I was a kid. He gets pissed
| off at it - I don't know why as it's a lovely bush - and lops
| it down to the ground. It's usually back within the year. I
| know sumac in particular is incredibly stubborn. When you're
| trying to remove them in prairie management, the general
| practice is to lop them off a couple inches above the ground
| and then apply herbicide to the cut. Otherwise and sometimes
| even in spite of this, they just grow right back.
|
| Historically, the prairies would burn every couple years.
| Native prairie grasses and flowers are adapted for this and
| regrew, but shrubs and less-established trees didn't fare as
| well. When humans figured out how to prevent the wildfires,
| those shrubs and young trees started to move into the
| grassland. Sumac tends to be one of the first infiltrators.
| Once a sumac stand is established, they shade out the grass.
| Larger trees follow and what was once grassland becomes a
| forested area.
| samatman wrote:
| It's odd that we have such fine-grained words for this
| practice, but this is coppicing, not pollarding. Coppicing
| is done near ground level, pollarding higher up the trunk
| of the tree.
|
| A testament to how important agroforestry was to the
| English people, I suppose.
| ocdtrekkie wrote:
| I have a weed bush I deal with called buckthorn, and you can
| cut every branch down to the ground and that sucker is coming
| back in a week or two unless you get a stump grinder.
|
| This document from the Minnesota DNR expresses just how hard it
| is to kill it:
| https://files.dnr.state.mn.us/natural_resources/invasives/te...
|
| Specifically it suggests cutting it to the ground and then, if
| you don't want to use herbicide, to cover it with a black
| plastic for one to two _years_. And it says the seeds it drops
| remain viable for five.
| goldenkey wrote:
| Couldn't you just burn it?
| ocdtrekkie wrote:
| I live in a suburban enough area that I strongly suspect
| that'd be illegal, even if I felt confident I wouldn't burn
| down the trees I don't want to burn down.
| zokier wrote:
| All these "foo is not bar biologically" types of articles make me
| think that is biology lacking some categorization or model that
| actually corresponds better with the world as we perceive it.
| SNosTrAnDbLe wrote:
| The world will always be more complex than our models
| (irrespective of the field). Even Math is by definition
| incomplete. Its nice to take a step back and appreciate the
| complexity of the world that we live in without judging our
| models.
| Consultant32452 wrote:
| It's in group out group signaling. It's important to have your
| own in group language and categories to separate yourself from
| the out group.
|
| It's why we have scientific names in Latin, military beds are
| called a rack, and whose life matters.
| [deleted]
| svara wrote:
| That's a rather naive take that you're attacking all of
| "biology" with. The article doesn't even state what you
| criticize it for - it doesn't say that there is no such thing
| as a tree, it says there is no such thing _phylogenetically_.
|
| All of these systems of categorization are necessarily
| arbitrary in a way, since all of life is a big messy tangle of
| related organisms, and there is nothing to clearly tell you
| where to draw lines to separate them. That's the source of your
| confusion right there. Turns out, groupings that seem obvious
| to someone who hasn't looked closely can be really difficult to
| delineate clearly.
|
| So, biologists try to define rules by which to do that, which
| they can apply unambiguously. One of the possible rules to
| apply is that groups should be paraphyletic, i.e. only contain
| (some of the) organisms with a shared common ancestor, or
| monophyletic, i.e. contain all of the organisms with a shared
| common ancestor.
|
| Other groupings do not fulfill those criteria, those are called
| polyphyletic. Grouping organisms that way has somewhat gone out
| of fashion, now that evolution is well understood. What this
| article is saying is that trees form a polyphyletic group. In
| addition to that, even just defining a group (for example,
| based on structural or functional properties of the plant) that
| neatly maps to what people usually consider to be a "tree" is
| harder than it sounds. Since all of that might be surprising,
| you see it here on HN.
| repsilat wrote:
| > _What this article is saying is that trees form a
| polyphyletic group._
|
| This example seems reasonable in that way because there isn't
| some parallel definition of "tree".
|
| A layman, on hearing that (according to evolutionary
| biologists) "birds are dinosaurs" might reasonably assume
| that evolutionary biologists will also say that dolphins are
| fish. Alas, no -- "dinosuar" has a parallel phylogenetic
| definition that differs from the lay one, but "fish" doesn't.
|
| Botany is a source of this sort of confusion a lot.
| Raspberries and strawberries and blackberries are _culinary_
| berries, but not botanical berries. (A tomato is a botanical
| berry, though. -EDIT, said culinary originally.)
|
| I'm of two minds about it. If you need a word, maybe it's
| best to use an existing one when there's a large overlap. But
| then again, the closeness of many _legal_ terms ( "murder",
| say) to their lay definitions arguably causes more confusion
| when those definitions differ. With biologists "just assume
| their meaning is totally different to yours" is a good
| heuristic, and with lawyers (or mathematicians talking about
| "knots" and "sets") the similarity causes perhaps more
| difficulty.
| jessaustin wrote:
| What sort of berry is a tomato? I would have thought
| culinarily it would be a vegetable.
| repsilat wrote:
| Whoops, corrected, thanks.
| intuitionist wrote:
| It's a botanical berry but a culinary vegetable (as are
| the other fruit we eat from the Solanaceae)
| jameshart wrote:
| I mean, dolphins _are_ fish, in the sense that the most
| recent common ancestor of all modern fish is also the
| common ancestor of all modern dolphins. Very few animals
| aren't fish in this sense though. Birds are also fish.
|
| What's surprising is that you can exclude sharks and rays
| from your definition of 'fish' and this statement will
| still be true - you are more closely related to a salmon
| than a salmon is to a shark.
| goldenkey wrote:
| It's not just a rooted tree, it has crossovers and
| cycles. Trying to draw boundary boxes is a fools hardy.
| jameshart wrote:
| This is true, when you zoom in closely, but when you zoom
| out, it is _quite_ treelike. phylogeny isn 't _useless_
| just because the process of speciation isn 't
| instantaneous.
| User23 wrote:
| It's very helpful to learn to recognize lumper versus
| splitter arguments. Pointing out that lumping things
| together or splitting things apart is arbitrary just
| isn't very interesting. What is interesting is why some
| things are lumped and some are split. For example why are
| polar bears and grizzly bears considered different
| species? They can breed just fine after all.
| jameshart wrote:
| Right, and when you notice that a bunch of organisms
| share a trait, the fact that they share that trait in
| spite of their common ancestor not sharing it is
| inherently _interesting_ , right?
|
| We know that traits are heritable, so when you have a
| bunch of different organisms that exhibit the same
| characteristic, if you can trace back and determine they
| are all specialized descendants of some ancestor which
| first developed that characteristic, that's the complete
| story right there.
|
| But when we see the same behavior appear in different
| organisms without them sharing a common root for that
| characteristic that's _interesting_ precisely because we
| need another means to explain it.
|
| I mean, if grizzlies and polar bears could interbreed
| even though their nearest common ancestor was, say, some
| kind of small Cretaceous rodent, then weld have some
| explaining to do, right?
| User23 wrote:
| Absolutely. I find the cladistics approach appealing. On
| a bit of a tangent I did some searching and found
| this[1]. Nightjars are cool!
|
| [1] https://scienceblogs.com/gregladen/2010/09/09/one-
| could-say-...
| TeMPOraL wrote:
| I honestly thought this article would be about the _other_ kind
| of trees - the "trees of life". Because these aren't trees
| either. General population is just taught they are, which is
| one of those categorization that _doesn 't_ correspond well
| with the world.
|
| Life is just one big chemical reaction that's been going on for
| a billion years. It's structured only so-so - not perfectly. In
| sexually reproducing organisms, genes of two parents mix up
| randomly(ish) to create offspring, which would suggest a tree
| structure - except when it doesn't. Sometimes genes mix wrong.
| Gametes can and do accumulate random mutation. Viruses
| occasionally inject genes into places where they can get
| carried to future generations. Incest happens. Not all life
| forms reproduce sexually. Cells can pick up free-floating
| genetic information from the environment. At the level of
| single-cellular organisms, this is arguably the bulk of what's
| happening. Bacteria exchange genes like people exchange cooking
| recipes.
|
| The way you take this messy reality and arrive at a "tree of
| life" (and it's always _a_ tree of life, not _the_ tree of
| life) is by looking at how some set of genes seem to have
| spread across life forms. It 's always conditioned on what
| particular genetic marker you're looking at, and is equivalent
| to selecting _an_ interesting spanning tree in a highly
| interconnected graph. Pick a different genetic marker, you 'll
| get a different tree.
|
| Sure, once you get to studying trees and dogs and humans, gene
| transfer becomes more tree-ish - but it's a difference of
| degree, not of a kind.
| owl57 wrote:
| _In sexually reproducing organisms, genes of two parents mix
| up randomly(ish) to create offspring, which would suggest a
| tree structure._
|
| No? Tree structure is a simplified model of asexual
| reproduction, where each organism has one parent, not two.
| wongarsu wrote:
| Agreed. Sexual reproduction suggests a unidirectional
| acyclic graph.
|
| Unidirectional acyclic graphs also allow for Neanderthals
| reproducing with humans, for random mutations, for bacteria
| exchanging genes asexually, and for genes inherited from
| virus infections. But "tree of life" is just so much more
| sexy than "unidirectional acyclic graph of life"
| owl57 wrote:
| DAG of life sounds pretty sexy if you ask me, but yes, I
| wouldn't try selling that anywhere outside CS or
| bioinformatics department.
| xipho wrote:
| Why not? I've heard it before in conversations. Search
| "inferring species networks from gene trees". Look at the
| math in RaXML, MrBayes, etc. The intersection of two
| different fields is often the most interesting, _if_ you
| can communicate between both.
| masklinn wrote:
| And at the phylogenetic level even a dag might be too
| restrictive due to horizontal gene transfers.
| watwut wrote:
| Biology does not lack such a thing. The subset shown in HN lack
| it, because people here like such content.
|
| The biological classification matches intuition in overwhelming
| majority of situations.
| da39a3ee wrote:
| Nope. If you actually look at the biological / evolutionary
| biological literature you'll find that there is no shortage of
| people who have thought deeply about biological ontology. To
| get you on the right track, most biologists agree that
| recognized entities should correspond to the historical
| evolutionary process. Plenty of discussion about the details
| there though.
| AndrewDucker wrote:
| Why would you think it necessarily would?
|
| Imagine that we had grouped together all of the animals that
| were purple. Or all of the animals that were edible. That
| wouldn't mean that there was an evolutionary link between them
| that could distinguish them from all the things that weren't
| purple or edible.
| jameshart wrote:
| Well it could matter if someone has, say, a 'tree nut'
| allergy, and we are trying to determine whether a 'nut' from
| a plant that doesn't seem tree-like visually could
| potentially trigger that allergy...
| timeslip1523 wrote:
| I think the point is that relatedness is just one property,
| and not the one that actual matters in an immediate practical
| sense. Does it really matter that whales and dolphins are
| mammals, and technically aren't fish? Yeah, it's why they
| hold their breath instead of having gills- but
| whalers/fishermen work off of long lists of specifics, not
| biology textbook classifications.
|
| In terms of practicality, a duck-typed classiciation system
| that means that deals neatly with convergent evolution sounds
| great. Keep your phylogenetic tree system for looking at
| phylogenetic trees, give me the classification that groups
| together everything that's purple, everything that swims,
| etc.
| slver wrote:
| We can throw all those properties in a database and we're done.
| A name will never be exhaustive categorization, because we
| still need names to resemble "what it looks like" and "what it
| looks like" doesn't have to correspond to "what it works like"
| or "where it came from".
| devoutsalsa wrote:
| I was talking to an astrobiologist a couple years ago,
| wondering what she looks for as signs of life. We got into
| talking about all sorts of things, from prions to the LUCA
| (last common universal ancestor). At some point when had asked
| enough questions about what is and isn't alive, and she
| basically said it's not even clear what is and isn't biology.
| astrange wrote:
| Local decreases in entropy seems like some kind of definition
| of life, but presumably it has to get big enough to start
| changing the atmosphere for anyone to notice it from another
| planet.
| pishpash wrote:
| Then hurricanes would be life.
| nsonha wrote:
| hey stupid question, what is entropy, how do you measure
| it?
| kergonath wrote:
| It's not a stupid question at all. Entropy is a made up
| number like energy. In a physical system it is related to
| how many arrangements of atoms/molecules/things there can
| be that would result in the system being in the state you
| can see.
|
| Energy tells you how difficult it is to put a bunch of
| particles (atoms, for example) in a given state. Entropy
| is how many of such states are possible. Ordered states
| (like crystals) have lower entropies than disordered
| states (like liquids), because there are fewer ways of
| arranging atoms and still get a crystal compared to the
| combination of possible positions for each atom in a
| liquid. In systems that are isolated (i.e. they cannot
| exchange energy with anything else), entropy cannot
| decrease on average. In non-isolated systems, anything
| goes and entropy can go up or down locally all the time.
|
| We don't measure it directly. What we can do usually is
| measure how much something heats when we give it energy,
| and work from there to deduce any entropy change using
| equations from thermodynamics or statistical Physics. It
| is impossible to measure an absolute entropy in general
| (in the same way as it is impossible to measure an
| absolute energy in general).
|
| There are lots of caveats, asterisks, and cases that look
| like exceptions; that's a quick and dirty description.
| xaedes wrote:
| > In a physical system it is related to how many
| arrangements of atoms/molecules/things there can be that
| would result in the system being in the state you can
| see.
|
| Mind if I ask follow-up question, what is a "state"?
|
| Doesn't the entropy change when I change my definition of
| the state? If I go to the extreme and there is only one
| kind of state, an actual arrangement of particles, fields
| etc., the entropy would be the same of each and
| everything (one possible arrangement per state).
|
| Does that make entropy an entirely subjective measure?
| TchoBeer wrote:
| iirc, a macrostate has a canonical definition (something
| like energy, the number of particles, and the volume)
| kergonath wrote:
| > Mind if I ask follow-up question, what is a "state"?
|
| Sure. Actually there are two main things we call states.
| The first one (macroscopic state, or macrostate) is what
| we think as characteristic properties of a bit of matter,
| e.g. "1 kg of liquid water at 300 K under atmospheric
| pressure" compared to "1 kg of solid water at 250 K under
| atmospheric pressure".
|
| The second one (microscopic states, or microstate) is the
| way the particles that constitute this bit of matter are
| arranged. The naming is a bit unfortunate and it can get
| technical quite quickly, but the distinction between
| macroscopic and microscopic states is crucial.
|
| So, a more precise version of my previous post would be
| something like that. In the liquid example, there are
| many, many ways of distributing the H2O molecules that
| would result in the same macroscopic description. This
| means that there are many microscopic states that are
| consistent with the macroscopic state we observe. And,
| looking at a glass of water, we cannot say where the
| molecules are.
|
| On the other hand, in a perfect ice crystal, the
| positions of all the atoms constituting al the H2O
| molecules are uniquely determined by the crystal
| structure. So, looking at a perfect ice cube we can say
| where every molecule is. It gets a bit more complicated
| in reality because no crystal is ever perfect. There are
| defects that introduce some disorder, so there are more
| than one microscopic state, but much fewer than in the
| liquid.
|
| Entropy is larger for things that have more microscopic
| states consistent with their macroscopic state. You can
| also see here a hint of the link with information entropy
| in CS, if you think about the number of microscopic
| states as our knowledge of the molecules' positions.
|
| > Doesn't the entropy change when I change my definition
| of the state? If I go to the extreme and there is only
| one kind of state, an actual arrangement of particles,
| fields etc., the entropy would be the same of each and
| everything (one possible arrangement per state).
|
| It does _sound_ very subjective. The conventional naming
| is a bit unfortunate and a consequence of the historical
| roots of statistical Physics in 19th-century
| thermodynamics. After all, there is no clear boundary
| between macroscopic and microscopic.
|
| If this bothers you, you can say that "macroscopic"
| refers to the thing you are looking at as a whole, and
| "microscopic" to its constituents. This framework works
| as long as the stuff you are studying is made up of
| smaller things. We commonly use atoms and molecules in
| examples because it is somewhat intuitive, but you could
| consider an atom itself as a macroscopic system and its
| quarks as its constituents. Or the universe and its
| galaxies clusters.
|
| The caveat is that the mathematical formalism is exact in
| the limit where the number of constituents is infinite,
| but might break down if their number is too small. That's
| why the distinction between macroscopic and microscopic
| is helpful.
|
| > Does that make entropy an entirely subjective measure?
|
| In a way, a bit. You can define the constituents
| seemingly arbitrarily (like considering molecules, or
| atoms as separate entities or not, adding electrons,
| etc). Adding more details gives a more accurate answer,
| but at some point it becomes irrelevant. So it is
| actually less subjective than relative.
|
| To keep (ab)using the water example, a molecule is made
| up of 3 atoms, each one having a position (3 positions,
| each one being a 3-dimensional vector, so 9 parameters in
| total). But when grouped in a molecule these positions
| are not independent, and need to be consistent with the
| O-H bond length and the H-O-H angle. A molecule is
| characterised by a position (3-d vector), an orientation
| along the axes of the reference frame (3 other
| parameters), an angle and two bond lengths (again 9
| parameters in total). So there is no more information if
| you describe the ice cube as a collection of atoms than
| as a collection of molecules, even though the choice
| seems arbitrary.
| BlueTemplar wrote:
| Yeah, it is (though the subjectivity might vary).
|
| Take a deck of cards, say, a pre-ordered one
| (technically, you know what microstate it's in) - so
| let's say that its "disorder" is "zero", and your entropy
| about it is zero.
|
| Now shuffle it face down really well, now both its
| "disorder" and your entropy about it is pretty high (it
| has a specific microstate that you don't know, and the
| ensemble of all potential microstates form a macrostate).
|
| Now look at this shuffled deck face up again - it's
| "disorder" is still high, but now your entropy about it
| is zero again, because you know what microstate it's in.
| kergonath wrote:
| Be careful that when you're doing that you basically add
| variables to your macrostate, to the point where entropy
| itself is meaningless. This type of example is commonly
| used in CS, but does not correspond at all to a physical
| system. Bear in mind that information theory's entropy
| and statistical Physics' entropy are quite different in
| the details.
| BlueTemplar wrote:
| What variables am I adding ?
|
| In what details are they different ?
|
| http://www.av8n.com/physics/thermo/entropy.html
|
| EDIT : Perhaps more relevant:
|
| http://www.av8n.com/physics/thermo/s-relevance.html#ch-s-
| rel...
|
| EDIT2 : A specific example where both the Thermodynamic
| entropy and the Shannon entropy can be experimentally
| seen to be equivalent :
|
| http://www.av8n.com/physics/thermo/expt-basis.html#sec-
| demag
|
| EDIT3 : Ah, found the chapter discussing this specific
| point :
|
| http://www.av8n.com/physics/thermo/entropy-more.html#sec-
| s-i...
| kergonath wrote:
| > What variables am I adding ?
|
| The state of each card. If you define a macrostate in
| such a way as it can have only one microstate, then yes,
| entropy is 0. It is also completely artificial.
|
| > EDIT : Perhaps more relevant: >
| http://www.av8n.com/physics/thermo/s-relevance.html#ch-s-
| rel...
|
| I am not impressed with that website in general, but in
| this instance I don't see anything wrong with that
| section. Note in particular:
|
| > Very roughly speaking, the items higher on the list can
| be assigned to the "information theory" camp, while the
| items lower on the list can be assigned to the
| "thermodynamics" camp. However, there is tremendous
| overlap between the two camps.
|
| There is indeed some overlap (I have personally worked
| for a couple of years on applying information theory to
| calculate entropy in glass-forming materials), but not
| enough that you can just apply random concepts from one
| field to the other. Basically, your interpretation is
| that "we know a lot about the system, therefore entropy
| is low", whilst in a physical system it's the other way
| around: "entropy is low, therefore we know a lot about
| it". Knowing something does not change the state of the
| system you are observing.
|
| > EDIT2 : A specific example where both the Thermodynamic
| entropy and the Shannon entropy can be experimentally
| seen to be equivalent : >
| http://www.av8n.com/physics/thermo/expt-basis.html#sec-
| demag
|
| Entropy goes to zero when spins align, but it does not
| mean that entropy is non-zero until we check that the
| spins are aligned. Entropy itself is whatever it is even
| before we bother calculating it, and we can estimate it
| different ways. Sure, we can use Shannon's formula in
| some cases, which is really just Boltzmann's formula with
| different units.
|
| Entropy is a thermodynamical property of a bit of stuff,
| regardless of what we know about it. The conservation of
| Gibbs free energy does not suddenly break down because we
| stop (or start) looking.
| BlueTemplar wrote:
| It's a somewhat obsolete term for "lack of information" :
|
| http://www.av8n.com/physics/thermo/entropy.html#sec-s-
| not-kn...
|
| (Yes, it is indeed context-dependent.)
| kergonath wrote:
| Local decrease in entropy does not necessarily indicate
| life, merely an non-isolated, out-of-equilibrium system.
| astrange wrote:
| I was using a very loose definition of entropy there,
| more like organization, but for instance if the
| atmosphere starts displaying large amounts of oxygen or
| the surface is suddenly covered in metal then something
| is happening there.
| jhbadger wrote:
| But important thing to understand is that phylogeny isn't just
| some arbitrary classification scheme -- it is dealing with the
| actual world and its history. It's an interesting observation
| about the real world that things people call "trees" evolved
| independently.
| kergonath wrote:
| In this case the problem is everyday language, more than
| biology. There are lots of things that have the same common
| name but are quite different from a biological point of view.
| Several species or entire genera can have the same English
| name.
| da39a3ee wrote:
| Why would anyone expect "trees" to be monophyletic?
| da39a3ee wrote:
| I'm sorry, I should have explained the jargon here.
|
| A "monophyletic" set of organisms is defined to be a set for
| which there exists a common ancestor, which ancestor has no
| descendents outside the set. (Try to ignore sexual reproduction
| when thinking about that; think about "lineages" of "species"
| first.)
|
| This concept is the basis of modern biological taxonomy.
|
| A "tree" is a plant with very pronounced woody structures.
|
| There is nothing about the botanical concept of a "tree" that
| immediately suggests they should be monophyletic. At least to
| someone with general biological knowledge, it would seem
| entirely possible that this woody morphological form could have
| arisen multiple times independently, and indeed that is what
| one would suspect, given knowledge of the prevalence of
| convergent evolution elsewhere.
| tooltower wrote:
| Wait, why is banana classified as a tree in this diagram? I'm
| pretty sure they don't have any wooden core.
|
| I'm definitely no expert, but as kids in the nineties, banana
| plants were always cited as _the_ example of how large plants are
| not always trees. Did they get recategorized?
| goldenkey wrote:
| The hardy banana tree is actually an herbaceous perennial (the
| world's largest) despite being referred to as a tree.
| amluto wrote:
| I was entertained to learn that silversword and yucca, which live
| in similar conditions, look quite similar, and have similar
| flowering habits, are utterly unrelated. One is a dicot and one
| is a monocot!
| aldeluis wrote:
| Reducing reality to semantic ontologies is a risky sport and a
| pleasure for the inquisitive ones.
|
| Forget Godel's wall (incompleteness theorems) and keep digging
| searching for imperfect answers to build our existencial puzzle.
| Thank you for the post.
| k__ wrote:
| I once read about a conspirarcy theory that trees don't actually
| exist anymore and the plants we take for trees today, are
| actually glorified bushes.
|
| The theory goes on about how mountains are actually the stumps of
| trees of the past, which, in turn, were thousands of miles high.
|
| The theory came from the flat earth direction.
|
| The title reminded me of this and I found the idea hilarious back
| when I read it.
| geoduck14 wrote:
| I haven't had my medicine this morning, and your comment sent
| me in to the weirdest daydream about mountains transforming
| into trees and bushes dancing around.
|
| Thanks!
| goldenkey wrote:
| Do you have ADHD?
| [deleted]
| umanwizard wrote:
| This was popularized by a YouTube video called "There Are No
| Forests On Flat Earth Wake Up". For those who feel like going
| down a flat earth rabbit hole :)
| th0ma5 wrote:
| And if you want a chaser for any flat Earth material check
| out https://youtu.be/JTfhYyTuT44 "In Search of a Flat Earth"
| probably the best documentary I have seen on conspiracy
| theories.
| ocdtrekkie wrote:
| I don't want my YouTube recommendations tainted by that.
| umanwizard wrote:
| Actually I'm not sure whether it was on YouTube originally.
| It's not now, as far as I can tell. But there are some
| interesting mainstream articles on it if you Google that
| string.
| djbebs wrote:
| That actually sounds like a cool concept for fantasy
| worldbuilding
| masklinn wrote:
| It's a pretty regular parallel / idea e.g. https://www.reddit
| .com/r/Fantasy/comments/a6w2ee/ancient_tre...
|
| Depending what the final goal of the worldbuilding is, the
| difficulty might be making it into something useful /
| relevant.
| HelloNurse wrote:
| Myths like Yggdrasil must be based on reality...
| Izkata wrote:
| Meet the Hyperion tree (though it's in California):
|
| https://i.imgur.com/91lnAGL.jpg
|
| https://en.wikipedia.org/wiki/Hyperion_(tree)
| slver wrote:
| They're not glorified bushes, they are charging and
| communication hubs for birds.
|
| Because as we know... birds aren't real, either.
| pcthrowaway wrote:
| This seems like an innocuous parody truther movement -
| https://www.vice.com/en/article/xg8p4n/birds-arent-real-
| they...
|
| But I really wished they would have picked something else.
| There are tons of posters and "legitimate"-sounding text
| positing this theory, which very likely has led to people
| harming birds to "expose" the truth of mechanization
| samatman wrote:
| This is called, on Twitter, "making up a guy and then
| getting mad at that guy".
|
| Please don't.
| jameshart wrote:
| Complete side-tangent: as a British-English speaker living in the
| US I have _just about_ grown able to tolerate the American
| pronunciation of 'herb' with a silent H, so it doesn't jar me too
| much when I read a text that says "an herb".
|
| But I haven't encountered enough scientific spoken American to
| have developed an instinct for whether or not Americans actually
| pronounce the 'h' in 'herb-' words like 'herbivore' or
| 'herbaceous'; so in this text I was a bit thrown by encountering
| both "a herbaceous plant", and "an herbaceous plant". Wondering
| whether this is situational pronunciation? A variation on the
| hyper correct 'an precedes words that start with H if the first
| syllable is unstressed' rule that gives you "an hotel" and "an
| historic event"? Just error?
|
| Can anyone enlighten me?
| Gibbon1 wrote:
| There is formal writing, informal writing.
|
| Words that are not commonly used in spoken English may often be
| mispronounced. Common words are subject to drift.
|
| Then there are regional variations in the US. But then also
| people move from one region to another. And of course different
| dialects may coexist.
| tingletech wrote:
| I thought you just softly swallow the `h` when there is an `an`
| so it starts with a vowel sound. I can't think of any time I've
| ever heard or said "an hotel" and it sounds very awkward to me,
| but herbaceous and historic can warble.
| analog31 wrote:
| But they say "an historian."
| [deleted]
| jameshart wrote:
| who is 'they'?
| IshKebab wrote:
| People who erroneously say "an historic" and pronounce
| the h.
| jameshart wrote:
| That's not an error. It can be an affectation, but in my
| native southern English middle class somewhat Radio 4
| accent it's perfectly reasonable to pronounce 'an
| historic' basically the same as 'unhistoric' - or equally
| to pronounce 'a historic' with a stressed a, basically
| the same as 'ahistoric'. Pronouncing it with an
| unstressed schwa for 'a' then an unstressed 'his' sounds
| awkward to my ear. And I would never drop the 'h'. That
| would sound common :)
| nerdponx wrote:
| American here (Northeast USA). It varies by person and possibly
| by local accent. But people are generally consistent in whether
| they pronounce the leading "h" or not. Most people do not
| pronounce the "h".
|
| As for "an" and "a", I was taught to follow the rule you stated
| in school. To my eye, using "a" is informal and mimicking
| speech, whereas "an" is "correct".
| smhost wrote:
| https://www.ahdictionary.com/word/search.html?id=A5000200
|
| > Usage Note: In writing, the form a is used before a word
| beginning with a consonant sound, regardless of its spelling (a
| frog, a university, a euphemism). The form an is used before a
| word beginning with a vowel sound (an orange, an hour). * An
| was once a common variant before words beginning with h in
| which the first syllable was unstressed; thus 18th-century
| authors wrote either a historical or an historical but a
| history, not an history. This usage made sense in that people
| often did not pronounce the initial h in words such as
| historical and heroic, but by the late 19th century educated
| speakers usually gave their initial h's a huff, and the
| practice of writing an before such words began to die out.
| Nowadays it survives primarily before the word historical. One
| may also come across it in the phrases an hysterectomy or an
| hereditary trait. These usages are acceptable in formal
| writing.
| jameshart wrote:
| I don't think that answers my question. The article contains
| both 'an herbaceous' and 'a herbaceous'. And does not appear
| to be 18th century in origin.
| bostonpete wrote:
| I think it would depend on pronunciation. Since
| "herbaceous" isn't a term you hear often, most people
| likely don't have a good instinct for how they "should"
| pronounce it. Seems plausible that the author concluded one
| pronunciation made more sense at one point during writing
| and the other pronunciation at a different point. Or maybe
| one was just a typo. ;-)
| smhost wrote:
| In the entry for "herbaceous": (hur-bash@s, ur-)
|
| According to the Usage Notes, both "an" and "a" are correct
| in written form (since both pronunciations are correct). If
| you're reading it out loud, "an herbacious" should be
| pronounced with a silent "h", and "a herbaceous" should be
| pronounced with an aspirated "h".
| Izkata wrote:
| > as a British-English speaker living in the US I have just
| about grown able to tolerate the American pronunciation of
| 'herb' with a silent H, so it doesn't jar me too much when I
| read a text that says "an herb".
|
| As someone who grew up in the US and has never left the
| country, "an herb" really bothers me because I've always
| pronounced the "h".
| stephenhuey wrote:
| If I personally say "herbivores and omnivores" I find myself
| wanting to pronounce the h sound. But my Merriam Webster
| dictionary implies with parentheses that some Americans do not
| pronounce it:
|
| '(h)@r-b@-,vor
| kazinator wrote:
| The difference is more pronounced (pun intended) when an
| indefinite article is attached: "an herb" versus "a herb".
| stephenhuey wrote:
| True, but I tend to think of choosing the indefinite
| article appropriate to how I pronounce the word. So if I
| pronounce the h then I'd choose a, but since I don't I
| always go with an. But for herbivore, it would be a for me.
| :)
| Ericson2314 wrote:
| > While natural selection is commonly thought to simply be an
| ongoing process with no "goals" or "end points", most scientists
| believe that life peaked at Welwitschia.
|
| Is this (joke) because it's a living fossil with a long lifespan,
| or something more?
| bediger4000 wrote:
| On one level this is the same thing as a biologist saying
| "there's no such thing as a fish". The semantic category of
| "fish" includes sharks, bony fish, lung fish/coelecanths and
| lampreys and hagfish. They're only distantly related.
|
| On another level, should we obtain knowledge of a distant, life-
| filled world orbiting a distant star, we could expect it to be
| forested by woody plants, and filled with crabs.
| a_bonobo wrote:
| >Why don't more plants evolve towards the "grass" strategy?
|
| Fun story!!! Seagrasses are like whales, in that their ancestors
| lived on land, and now they live completely submerged.
|
| Seagrasses are nowhere closely related to grasses. Quote: 'They
| just... both did that.' They're at least three, maybe four
| distinct 'back to the sea' events in the seagrasses, with
| distinct lineages that went back separately, but show convergent
| loss of genes.
|
| Most seagrasses look a lot like grasses, bringing me back to OP's
| 'grass strategy' - under water it's a very successful strategy!
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