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Hot Take: bramble edition

I've seen a catagory on this forum that has devil's claw listed as a quasi carnivorous plant, so why not include other plants that are known to snare animals? I've seen multiple reports that thick patches of raspberries and other similar plants will trap larger animals like sheep resulting in them dying and decaying around the plants. So why not add them to the list? Any thoughts?

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Because the protocarnivory is not due to the hooked seed pods. It is due to the glandular hairs ibicella has on its leaf surfaces. At this point no brambles are considered proto or quasi carnivorous. Being able to entangle has been rejected as a feature of carnivores be cause then, any sufficiently large shrub could be carnivorous.
I don't know if I agree with that logic. Sure, any shrub given a certain size could entangle an animal, but species with brambles have an adaptation that goes beyond self defense. I'm not sure how one would ethically construct am experiment involving the sufficiently large bush and bushes with brambles killing animals, but I'd wager the brambles give advantage. A sufficiently large coin dropped off a building might damage my car, but a wrecking ball would be more consistent. I'd also say in the specific case of raspberries the material properties of the stems play a role too. Just my $.02. Not that it's worth terribly much.

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There is no evidence of such. The "quasi" carnivory of Proboscidea, Ibicella, etc. has already been rejected because they do not reliably show any digestive properties (either via direct production from the plant or using a proxy such as assassin bug associates or midge larvae), do not show direct uptake of nutrients from captured insects via the leaves (the only structures that are modified as traps in any carnivore genus), and there is no evidence of the plants doing significantly better in any way from the insects that are killed on them (increased growth, flowering, seed set etc.); those are the three general requirements for carnivory to be considered, and plants that in some way kill but do not perform digestion or direct uptake are often labeled "murderous plants" instead. Decay of an animal nearby a plant, for whatever reason related to the plant or not, does dot qualify for carnivory, only a case of useful fertilization via the standard root uptake method. There are several plants in South America with inward-pointing barbs on either leaves or stems known to hook birds or small mammals, but they are not classed as carnivorous because they do not experience the three key requirements and if nutrients are taken up from decaying animals, it's from the roots and would be no different from those plants that gather leaf litter around them to source nutrients from.
I understand the three qualifications in play, however I find them a bit arbitrary. If there are the more strict and accepted requirements for a plant to be labeled carnivorous, why is there no designation for opportunistic absorption of animal decomposition through the roots? If the decomposition is done by mycorrhizal fungus is that form of mutualism significantly different from roridula's association with the assasin bug? It's not as flashy, but the relationship is there.

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Because, frankly, decomposition of dead things in the soil and eventual uptake of the result via the roots is how the vast majority of plants get their nutrients, they do not have any special design for prey capture in this however so nothing special to set any of them apart in this way. Carnivorous plants do, and they are all leaf-based uptake, none root-based. Your example of mycorrhiza vs. Pameridea is significantly different in factor of Roridula have a structural form designed for prey capture and a direct symbiotic relationship with the insects wherein the insects release a liquid feces that can be directly absorbed by the leaves ie. digestion by proxy rather than directly by the plant, a one-step difference from other carnivores but still taking advantage of a resource no other plants can; the association with fungi for nutrient uptake and/or pathogen defense has no specific design for prey capture (predatory fungi are never plant-associated, nor capture prey for the purpose of the plants) and is common across most terrestrial plants, and makes no separation between decomposed floral vs. faunal matter. Drop a dead robin at the base of a tomato plant and it'll get nutrients in exactly the same way as if you dropped a bunch of old banana peels or leaf litter there. Drop a locust on a tomato leaf vs. into a Sarracenia leaf and there will be a visible difference in which plant does better, and a visible difference in mechanism.