Are Magnoliids Dicots or not quite?

According to this new recent Phylogenic Tree Study, Magnoliids are Sister to Monocots. Together they are sister to Eudicots. Does this make sense? Both Monocots & Magnoliids generally have petals in 3’s right?

Study Link : https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-025-02135-9

Also if Monocots have 1 Cotyledon, Eudicots have 2 Cotyledons, How many do Cotyledons do Magnollids, Basal Angiosperms & Gymnosperms have?

Does it even make sense to say Gymnosperms have Cotyledons?

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They’re plants.
That’s what I, being a lesser creature, say.
I’m leaving it to the people who know things.
Why am I posting here again?

It is clear flowering plant fall mostly into three parts (plus 3-4 smaller groups at the base):

true dicots (eudicots), monocots and old dicots (magnoliids).

How exactly they are related, it is not clear; it happened too long ago. APG IV has old dicots as the most basal of the three lineages, for which there is some molecular evidence, but it also makes sense in the morphological sense.
However, it is not clear and likely will never be clear exatly how this old groups of plants are related to eachother.

It looks like having 2 cotyledons is plesiomorphic (this state is ancestral), and only monocots as a groups deviated from that state, so true dicots and magnoliids kept the ancestral state. On the other hand, it also appears trimerous flowers are plesiomophic, where only eudicots diveiated (magnoliids also usually have 3 merous flowers, when segemnts are countable).
Magnoliids mostly share the old states, while eudicots and monocots possess some new states, as well as new ones.

magnoliids usually have 2 cotyledons, basal angiospersm generally have 2, but some have secondarily reduced one of them (Nymphaeales), and Gymnosperms usually have many cotyledones.

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Only Monocots are not Graftable right? Altho there’s a recent study proving that monocots are graftable at a Seedling level.
I ask because Monocots & Dicots have vascular bundles arranged differently, which affects how graftable they are. How are the Vascular bundles arranged in Magnoliids?

How are they arranged in Gymnosperms? How does this affect grafting, pruning, growth habits? In pines, you prune the “Candles” which are shoots because pruning older is permanent (Cuz for some odd reason, pines can grow back from the stump). Is that true for all Gymnosperms, whole Pinaceae family or just Pines (Pinus spp.)?

and why are Gymnosperm “Flowers” Called cones when they serve the exact same purpose as flowers?

I see, and what about the basal angiosperms? More complexity I assume? Nymphaeales have only 1 Cotyledon (Normally)?

Ah that makes so much sense when I look at a pine seedling germinating. For example these I thought were simply True Leaves. You mean in this example, these are actually cotyledons & the true leaves haven’t yet formed?

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Decacots?

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Your curiosity about these things suggests that you would both enjoy and benefit from a basic course in botany.

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Blockquote
Only Monocots are not Graftable right? Altho there’s a recent study proving that monocots are graftable at a Seedling level.
I ask because Monocots & Dicots have vascular bundles arranged differently, which affects how graftable they are. How are the Vascular bundles arranged in Magnoliids?

I do not know about graftability - this is aplicable sience, therefore I have little interest in it :)
I imagine in the lab, it should be possible? But not sure.

the vascular bundles of Magnoliids are similar to eudicots (the woody species have a cambium and are very similar to eudicots).Basal dicots and gymnosperms have wood that is also vaguely similar to eudicots, however, there are important differences (they lack true vessel elements (xylem), instead they have tracheids (precursor to true vessel elements)); but generally they function in a similar way to eudicots (it seems the best way to be woodyis to have a circular layer of tissue that adds bark on one and wood on the other side, so it appears as they have organised vessels).

For pruning, wood structure does not matter as mauch as the ability to meristematise specialised tisuue (meristems are clumps of undifferentiated cells at the growing tips of plant organs); generally, we can artificially make any lump of living plant tisuue grow an entire plant (we force it to meristematise), but in nature, species differ wildly in ability to resprout (i.e. meristematise or by having long lived dormant meristems).
Gymnosperms: Juniperus communis can resprout and grow coppiced, Abies alba cannot; Monocots: Yuccas can and will grow new growth points, but must palms (Arecaceae) will not, eudicots: Quercus pubescens like to grow coppiced (resprots after cutting), Q. robur usually does not, and those to spp. are not only in the same genus, but so closely related they form hybrid swarms).
Resprouting is an adaptation, and does not have so much to do with phylogenetic placement.

For Pines, the Pine I am most familiar with does not resprout (Pinus sylvestris)

Blockquote
and why are Gymnosperm “Flowers” Called cones when they serve the exact same purpose as flowers?

This also pends on definitions of what a flower is; it can absolutely be exapnded to include gymnosperm cones.
But generally, flower is a determinate shoot, terminating with leaves (anthers, carpels or both) that produce gametophytes, and they develop into a fruit* containing seeds.

Gymnosperm cones are neither determinate, nor do they terminate in fertile leaves, and they do not develop into a fruit containing seeds (juniper berries are whole cones, as if the whole apple flower would turn into an apple, but otherwise gymnosperm seed sit unprotected on a carpel . a pine nut is not a nut, but a pine seed, and you can just shake or tease it out, without separating layers of tissue - in true fruits you have to cut it if you want to get to the seed, unless it does it itself).

but; you could also say a flower is a short fertile shoot containing leaves involved in reproduction; that would expand the flower definition to cones, but also to lycopod strobili, and certain moss structures, as well as liverwort perianths/male spikes. This definition is not commonly used, but there are arguments for it in some contexts.

  • fruit is seed(s) contained within maternal tissues (carpels) - the simplest ones are called follicles, and when mature, they split open to reveal the seeds. A pod is a special type of follicle of the legume family -a bean is a pod - the single bean is a seed, and is wholly a new plant, while the bean pod is from the mother. All other angiosperm fruits are variation on the theme (i-e a nut is when a “pod” contains a single seed, and the pod walls become woody, berry when the follicles fuse together and become fleshy, etc.)

Those are cotyledons on the picture, yes.

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ah that makes sense. Different approach to structure plumbing that achieves the same function.

I wonder why that is? is it just a Pinaceae thing?

Wow very interesting closely related Oak hybrid swarms have this difference between resprouting & not. Hmm… I do see some Pine species resprout needles from the trunk but I thought it wasn’t the same thing.

Ah that makes a lot of sense. I’ve been calling them flowers.

ah… that’s why they’re called naked seeds or is it because Gymnosperm seeds lack a seedcoat? It’s interesting that Pines take 2 years to fully mature their fruits after pollination, are they other plants that also take 2 years?

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Northern red oak does that I think.

Some pines can resprout, like shortleaf pine, pitch pine, and pond pine.

https://research.fs.usda.gov/treesearch/52651

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The gymnosperm seed has a seedcoat (testa), but it matures exposed on the surfarce of the carpel (the carpel is flat). The carpels are scales in the cones (often its a bit more complicated than that, as they come in pairs, and the scale like is protecting the actual carpel hiddin betwen them)

In angiosperms, the developing seed is completely envelopped by a carpel (or a structure derived from a carpel). Tne enveloping carpel can then serve a wide variety of functions.

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Ginkgo still confuses me in this regard. Its “cones” seem more like drupes to me; as if the only reason they are called cones is because we classify ginkgo as a conifer, and therefore must define its fruits as cones.

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Ah yes… almost forgot about those. So that leaves just Pines & Red Oaks? Nothing else?

Yes those were the species I was thinking about, however will they resprout even if the whole trunk is cut down? Or is it only minor sprouting with leaves coming out of the bark?

“morphological adaptation (basal crook) that lowers dormant buds to the soil surface where they are presumably protected from fire to facilitate resprouting after topkill.”
I find this interesting, Lower Dormant Buds eh??? What happens if you prune these lower buds off, will they resprout again?

Ah… so the “Seedcoat” in gymnosperms is attached to the upper lip of the cone scales…
I’ve disected Spruce & Pine cones before, this makes a lot of sense.
Techically speaking, they aren’t naked seeds until the cones open right?

Ah yes… they are very interesting… Perhaps the exception to the rule (Actually in Nature Exceptions is the rule :joy:, there’s always exceptions somewhere & somehow.)!

Just like how some Dicots naturally have 3 Flower Petals, for example in Floerkea proserpinacoides. I’m sure there’s some Monocot that has 4 Petals & other exeptions.
Especially Magnoliids having both kinds of traits (Often petals in 3’s & Dicot style but not quite like Vascular Bundles).

Speaking of which, Ginkgos are sister to Cycads if that helps explain the weird exception? Maybe at this branch in the tree of life, spontaneously evolution or chromosome doubling happend to generate such unique traits?

Do Ginkgos also have similar plumbing system (Vascular Bundels) to all the other Gymnosperms or does Ginkgo have more of a Dicot & Magnoliid style vascular bundels?

The big difference is that all of the “fruit” of the ginko is actually parts of the seed. In ginko, the testa* is very thick and complex, and reminiscent of the structure of a drupe, difference being that in drupes, the layers froming the flesh and shell are derived from a carpel and are not part of the seed.

testa is, like carpel, derived from maternal tissue; hover testa is part of the ovule (bits of tissue surrounding the egg cell), and carpel is basically a leaf.
Angiosperms basically have another comlex layer of tissue surrounding the seeds.

Female cones of ginko are highly reduced, my interpretation is that each cone is just a sigle fertile leaf, with two ovules, and its amina reduced to basically nothing.

*(seed coating, angiosperms have it too, that is for example te peel of a bean or the brownish papery coating of the peanut, as well as the brwon skin of fresh wallnuts and pecans).

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Interesting… I wonder where Yew Berries & Gnetum fit in?

Hold up… if they have it too than how are they not “Naked” seeds?
Seed coat in Angiosperms is always maternal material (Part of the Mother Plant & not changed by pollen) right? This is why Crossing 2 bean plants doesn’t change seedcoat color in F1 only after F2. This is also why Corn Crossing affects the current Generation colors in F1 Immediately because they lack a seedcoat (Maternal Material).

If I were to cross 2 Pine species together, the seeds inside would have noticeable morphological change immediately in F1 right (Since it’s a Naked Seed without a Seedcoat)?

Just to clarify, Naked Seeds litterally is just the embyro right? So when we sow Pine seeds, we are litterally sowing the embyro (Even if it looks like it has a shell)?

Same question also extends to Magnoliids, they have seedcoats right? I’m thinking of Pawpaw seeds & surely the seed is protected by a seedcoat no?

The “nakedness” of conifer seeds refers to the little hole that in the ovary giving pollen direct access to the ovule, at “flowering” time. In flowering plants, the ovule is completely covered inside ovary tissue.

Seeds of both conifers and flowering plants have seed coats.

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WHoa!? I’ve never seen that tiny little hole? Or is this the same hole where water enters to germinate the seed?

ah… so it is called a seedcoat in conifers too.

No. It’s a tiny hole in the young ovule, closed in the seed.

I’ve never seen it, do you have a picture?

I haven’t seen it, either. It closes after pollination and isn’t seen in the seed. For a diagram, search for “micropyle” and maybe conifer seed.

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