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Carnivory...what IS it?

PlantAKiss

Moderator Schmoderator Fluorescent fluorite, Engl
OK...having just enjoyed a romp through the lively discussion (with a little game playing thrown in) going on over in the Quasi-Carn forum...I have a coupla questions.

Bear in mind I haven't read every CP book published nor am I a botanist, scientist, researcher or plant expert. So...I'm just asking...

What DOES determine a plant to be defined as "carnivorous"?

I read the "six qualifications" as being: 1) Attract 2) Retain 3) Trap 4) Kill 5) Digest 4) Absorb (ok...WHO came up with that criteria??)

Question 1: Is there any significant differenct between "retain" and "trap"...isn't that basically the same thing (even though it may be achieved in different ways...i.e....dew vs. flytrap)?

Question 2: Is there any significant difference between "digest" and "absorb"? In both cases there is some type of breaking down of the prey into nutrients which will then be used to the benefit of the plant.

Seems to me its only 4 criteria...Attract, Retain, Kill, Absorb. Ok, so I'm a simpleton.
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Question 3: What difference does it make if a plant uses an enzyme or bacteria to break down the prey...isn't the pertinent isse that it takes a separate living creature, ensnares it and breaks it down (whether by enzyme or bacteria) into useable nutrients?

Question 4: Because one plant may have more/stronger enzymes than another...does that make one plant more or less "carnivorous" than another one? Aren't both AS carnivorous because they are achieving the same end result regardlessof "strength" of enzyme?

Thoughts anyone?

Suzanne
 
PlantAKiss, I am not really sure where this is going, but OK.

Answer #1: Yes, there is a big difference between trap and retain. The plant has to catch or "trap" an insect and then it has to hold it or "retain" it. If it gets away then what is the point of trapping it.

Answer #2: Yes, there is a big difference between digest and absorb. The plant has to break down its prey into simplier components or "digest" before it can take in and use those components or "absorb" it.

Answere #3: If the criteria is to digest its prey then the plant doesn't accomplish this if it has bacteria to break down its prey for it? So bacteria does make a difference in the definition of carnivory.

Answer #4: Carnivory is not relative. It only describes certain plants that have an amazing habit not to seperate carnivorous plants as more or less carnivorous, but to classify them as a whole. Now not to say that enzyme strength isn't important . Enzyme strength determines how fast a plant can digest its prey not including the other abilities such as being a good traper, or unescapable traping mechanism which none alone can determine a more evolved carnivore.

Hope this helps.
 
Now you have gotten me interested in the subject. BTW where did you read the criteria for carnivory. I would like to look into this in more detail. Thanks.

P.S. Very interesting nice post, got me thinking.
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Don't know if I agree with you on point # 3 (may or may not agree on the other points either but I haven't thought about them too much yet
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If you take a termite as an example, they eat wood but are not physically capable of digesting cellulose. They cultivate bacteria in their guts that do the job and they absorb the byproducts of the bacteria.
I have never heard an argument against the statement that termites eat wood.

A similarly confused fatboy?
 
Fatboy if you are going that way, all of us depend on bateria to break down some food. I can not think of one animal that would live without the little things in their stomach. Its just that some plants may rely on bacteria completely. Also "EAT" isnt the best word you could of use, for it means to swallow for nourishment, or to partake in food. I enjoyed your example with the termite. I knew this fact already, but i hadn't thought of it that way. I didn't know your knowledgable in such subjects. Do you know about a beavers eating habits. Its bacteria can't break down food on the first run. And it doesn't get a much if all of its food absorbed the first time around. It still eates though digestion is a bit fuzzier. If you know what I am talking about then I am very impressed. If not ask me some other time. It is kinda sick. LOL.

Hope to discuss this farthur when you can think on it more.
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Going back to my termite example and what you have just said

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Its just that some plants may rely on bacteria completely.[/QUOTE]<span id='postcolor'>

Termites do exactly that, they ONLY consume wood and therefore rely completely on the action of the bacteria to process the cellulose and provide them with byproduct and not just as a supplementary source of nutrients.

Given the above it should be fair to say that termites consume (eat?) wood and survive solely on the action of bacteria to digest it. Is it not also then fair to say that a plant that rely's completely on bacteria to obtain nutrients from insects can still be considered to digest the insect?

I don't pretend to know much about any of this but what I have said above seems reasonable to me.

Cheers, Troy.
 
Not much into farm animals but I seem to recall something about cows useing bacteria to break down plant cellulose into something more digestable.
 
I didnt mean that they could survive without the bacteria. Of course they need the bacteria its justs that wood isnt solely cellulose. Cellulose is just in the cell wall in every cell and the bacteria are for digesting that which the termites cant, but the termite can digest the other parts. The digesting of the cellulose is very import and makes up the majority of the digested material, but not all. Its just that I persume that some plants cant digest anything and COMPLETELY rely on bacteria for all the digesting. This I think doesnt fit into the digestion criteria of carnivory. Though I believe that they are still are carnivorous and just found a creative way around digesting others would disagree.
 
  • #10
Hi Virus

Thanks for the reply. The criteria I listed came from a post in the Quasi-Carnivorous forum on Devil's Claw. Someone (can't remember who at the moment) listed those criteria for a plant meet in order to be considered carnivorous. And then some of the other following comments got me to thinking. (Not always a pretty thing...lol)

To my mind...I wouldn't consider prey as trapped if it got away. I guess I think of something as being trapped only if its retained...but that's just my way of thinking.

So I just got to thinking why it would matter if a plant benefited from enzymes or bacteria if both fed the plant either directly or indirectly. If the criteria is strictly digest by way of enzymes, then I guess the plants that use bacteria alone are not carnivorous.

And then I just wondered why the degree of enzymes would matter as to whether a plant was carnivorous or only sort of carnivorous. If heliamphora don't have as much enzymes for digestion as say a VFT, does it make less carnivorous?

Again, all these thoughts came from reading the Devils Claw posts.
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Thanks...interesting discussion.
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Suzanne
 
  • #11
Nah Suzanne I do agree with They on point # 1 - trapping and retaining being different.
Plants can trap but not retain. The one I am thinkiing of may be Amorphophallus but if not it's definitely one of the stinky flowers, attract beetles with a terrible stench. The bugs enter and remain trapped until part of the flower dies, and I'm sure it takes at least 24 hours. Once that has happened the part that has them trapped withers, and they are free to sod off and polinate another flower somewhere else.

In that case the insects are trapped but then released, which would disqualify the plant as carnivorous, in addition to the fact that the plant doesn't have most of the other features of a CP either.

That beaver stuff sounds rank.

Cheers, FB
 
  • #12
I am to blame for the criteria found in the Ibicella thread.
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It was in CPN volume 30, No. 2, p51. The author lists the source as being Juniper, B.E., Robins, R.J., and Joel, D.M. 1989, The Carnivorous Plants, Academic Press, London.

Chris
 
  • #13
Aahhh...I should have known it was a troublemaker like you.
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I think you should be voted off the island for that. hehehehehehe
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Actually I found it interesting. I hadn't read that before. It just got me to thinking.

Now...is there any significant difference between "insectivorous" and "carnivorous"? Is one more accurate than the other? Hmmmmm...Chris??
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Suzanne
 
  • #14
Absolutely no difference what so ever. They are two terms describing the same thing made at two different times.
 
  • #15
Based on the previous scientific posts I conclude that termites are not carnivorous.
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  • #16
lol... to fun..


first, I believe there is a difference between insectevorous and carnivorous, as I have seen plants catch more than simple insect, flytrap snapping on snails, and the rare oddity of course we have all heard of nepenthes trapping and digesting small monkeys, rats, and so forth... while not designed to it, the DO do it, and while they may lose a pitcher to rot, the Nepenthes most definately benefit from the influx of nutrients....

furthermore, I believe there is a difference TECHNICALLY between enyzme and bacterial digestion, but in the end, the plant has developed the ability to abosrb those broken down nutrients, regardless of 'who done it', and is there fore carnivorous...

Take the great carnivore, the Lion, we have known for decades that the lion is an opportunist, that it will steal kills from lesser lions, or other animals, and it will without a doubt, eat carrion... but it's a predator right?

the problem is not the plant/animal not fitting neatly into our classifications, it is the classifications themselves, Tyranosaur = Predator... umm.. NO, Tyranosaur = Creature of Opportunity, Thief, Carrion Eater, and Predator of SMALL animals (It's teeth where to shallow to rip meat chunks off larger creatures) Lion = Predator... again, no... we can go on... our classification systems aren't all right...

To anser your questions... think about this... we are basically saying if all carnivorous plants don't catch their food and digest it the same way (major difference between bacterial and enzyme) then one or two major classifications out there are NOT predatory?

Are you predatory? Are you a meat eater? How did you kill your food? Is purpera a predator because it lets the rain and dew fill up it's traps instead of doing itself like other sars and neps? What about the N. Bicalarata where the PLANT Traps, but it's symbiotic Golden ants rescue, then butcher the insect, only throwing enough back into the plant to keep it from attainint so much bio-mass it rots... Bicalarata does not do the ACTIVE killing in this case, it's more like a trapper taking his catch to the town butcher... what about roridula and it's assasin bugs? Or Drosophylum? do they BENEFIT from a deadly activity they encourage? YES.

If a plant 'seeks' to kill for the benefit of absorbing the victims nutrients, then it is carnivorous. The method in which it goes about accomplishing any of the goals, except absorbtion, which is either through specialize glands, or it's roots, then IMHO, it is a carnivore. (Do you drink beer? you are consuming the byproduct of bacterial decay... you are in effect... eating the droppings of micro-organisms... those same micro-organisms, and the little remains of the origional material... so... does that make you a carrion eater?
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  • #17
HEY!! Let's ease up on the beer. I'm not gettin touchy or anything (maybe a little twitchy from lack of)...
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  • #18
Micropoop???!!! Ewwwwww...I KNEW there was a good reason not to drink beer.
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Well like I said...I'm no scientist or anything but it seems to me a plant that benefits nutritionally, whether by digestive enzyme or bacterial assistance, from catching any kind of livng organism IS carnivorous. So in my m ind, byblis liniflora IS a carnivorous plant. And I don't think strength of enzyme matters. If they "eat", they are carnivorous. I can see the argument against "insectivorous" as they can catch/eat other things like worms (when handfed), small slugs and things like that aren't insects. Or...maybe even a 5-lb squirrel.........(couldn't resist&#33
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hee
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I'm sure there are botanists that would shake their heads over my feeble thoughts but I don't care. I love my byblis and its a CP to me...none of this "quasi" stuff.

However...the "quasi" plants are verrrry interesting. There is debate as to whether the passiflora foetida is carnivorous...it catches (and retains) insects in the feathery bracts surrounding the flower. But no one has established in what way this feature benefits the plant. I'd love to have one any way since I'm a passionflower nut. ( It is mentioned in the CP FAQs at www.sarracenia.com.)

Suzanne
 
  • #19
the only thing i can think of is that when the fruit ripens and falls to the ground, not only does it have the fruit itself to nourish the yound seed, but the decayed husks of all the inescts that were caught in the flower brachts as well...
 
  • #20
Now you done it Ram, you had to pull out the T-rex thing and I just can't hold back
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T-rex = Predator...umm... Yes. Exclusive predator... Maybe not, but then no predator is. T-rex has the built and body design of a predator. The teeth of T-rex were proportional larger than the teeth of other carnosaurs. The structure of the jaw is designed to allow for the gapping needed to deliver a killing bite and the teeth are serrated and arranged in such a way that, when the came together, they would result in a "cookie cutter" gash being taken from the prey animal. Also, the teeth are not designed for, or structurally capable of, the bone crushing/joint severing force needed by a scavanger. The muscle and bone structure of the head and neck are designed to take the force that would result from a Rex slamming headlong into it's prey and the muscle and ligament attachments in the legs point toward an animal capable of short burts of high speed. And then the largest argument against Rex being a scavenger, its size. It is not possible for so large an animal to survive by scavanging alone.

Back to the original topic, I don't really care how we define if a plant is really a CP. Are the Darlingtonia and Heliamphora any less interesting because they only use bacteria? I don't think so, I still like them and will still grow them.

So that is my $1.38 Take it or leave it
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Pyro
 
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