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Post by walterg on Mar 25, 2010 3:01:15 GMT -10
walterg: yeah, but in coprophage, 'phage' is usually pronounced with a long "A", kind of like "Kain". Oh, I beg to differ. The ending "-phage" is most correctly pronounced faZ (in X-Sampa notation), which decodes as follows: "f" is the voiceless labiodental fricative, as in "father" or "fill". "a" is the open front unrounded vowel as in the English word "car" as pronounced in Boston or Australia. "Z" is the voiced palato-alveolar fricative as in the English word "Vision". Some sources contend that it is pronounced feɪdʒ, but they are just plain wrong. After all, who are you gonna believe? Them or me? I'm a moderator! Quod erat demonstrandum.
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kain
Insignes
Posts: 144
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Post by kain on Mar 25, 2010 14:28:27 GMT -10
walterg: I stand delightfully corrected. @sam: Let us suppose, for the sake of argument, that Nepenthes pitchers are entirely non-specific in the types of prey they catch. Why, then, are the pitchers of such marvelously different shapes, colors, and sizes? Why the differences between upper pitchers and lowers? It seems to me there must be some kind of "general specificity" (how's that for a muddy term?) in which each species takes advantage of an array of common prey items present at their locale. I would expect some degree of niche specialization in most species of Nepenthes, particularly in species that are sympatric with other species.
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Post by leilani on Mar 25, 2010 23:18:40 GMT -10
kain ...
The easy answer would be that "diversity" is inherent in "nature".
The underlying assumptions behind the question being that these variations in morphology and color act to attract (lure) potential prey ...... and that these variations relate to specific prey ( ... an extension of the pollinator model). The trouble is that I have yet to see any convincing study that attempts to relate the specific morphological features of different pitchers to the attraction or capture of specific species (.. or “stuff”).
What has been suggested is that N. albomarginata specializes in the capture of termites ( ... I have made my skepticism regarding this hypothesis clear elsewhere on the forum), that N. ampullaria has evolved specifically to capture (?) falling leaves ( ... a hypothesis that turns everything we think we know about Nepenthes pitchers on its head and basically treats them as specialized roots), and now, that N. rajah, lowii, etc. have evolved specifically to attract birds and shrews and collect their skat ( ... a hypothesis that would appear to me to elevate a tangential occurrence (the collection of skat) to a causal explanation of pitcher evolution).
I do not deny these collection modalities but do question the suggestion that any one of these observational hypothesis is sufficient to the conclusion that the evolution of these pitchers are the direct result of these specific collections.
Look, I am not trying to deny evolution here. These plants have evolved to where they form traps and, along with the rest of the plant, these traps have evolved in response to selection. My point is that the factors that guide selection are manifold and, for the most part, unknown. The traps of Nepenthes work, some better than others, but they all work and this is the one reward that, we can fairly assume, drives their continued production. However, there is a big difference between saying that the “traps have evolved to be effective” and saying they have evolved “to trap singular species” or "the feces of particular species".
This is surely the case and I don’t want to get confused over “specificity”. The prey collected is specific within some fairly obvious parameters .... generally small crawling and flying insects. They don’t collect cows or anything too large to fit through the mouth of the pitcher. They collect a range of micro-organisms, insects and small animals. In fact, they collect anything that happens to be interested in the nectar they produce and/or unfortunate enough to fall inside.
An example of this would be nice. It seem to me that even sympatric species catch basically the same things. I see niche specialization as regards environmental factors like temperature but don’t recall any examples of sympatric species with different specialized collections.
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Post by leilani on Mar 29, 2010 23:38:08 GMT -10
Just one more and I promise I will let this thread die .... Clarke and the Shrew For old Dr. Clarke, All doubt was now gone. About his theory that rajah Is really a "john".
But people did doubt, That the great rajah grew, Just to provide, relief for a shrew.
So Clarke sat and he thought, "I know what I'll do, I'll prove to the world, That the pitcher's a loo!"
"I'll hide in the bushes; That's what I'll do. I'll hide and be quiet, Till a shrew has to poo!"
So off he went, Deep in the park. That's where he stayed, Till long after dark.
For days he waited, Set his own little trap. But no shrew came to visit, No shrew came to crap.
Then in the bushes, A noise he did hear. And as his heart pounded, The noise it drew near.
Up jumped a shrew, As sure as could be. On to the pitcher, Where Doc Clarke could see.
The shrew it ate nectar, While on rajah it sat. Then it lifted its tail, And that's where it shat!
It fell in the pitcher, And made a great "plop". Some got on the side, And some got on top.
Clarke pointed his camera, For just the right shot. And happy was he, With the "shit-shot" he got.
His proof now in hand, From the skeptics now free. It will make a great poster, Just wait and see!
With apologies kain ...... "free verse" is better than "bad verse". Just be glad that there are no drawings! ;D
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Post by walterg on Mar 30, 2010 7:22:30 GMT -10
To poop, or not to poop: That is the question: Whether this tumbler in the wind should suffer The dumps and floaters of soricid excretion, Or to take arms against a sea of insects, And by opposing eat them? Digest to live; No more; and by a Clarke to say we take The belly-ache and the thousand natural dungs That flesh is heir to, 'tis a consumption Devoutly to be shunned. To wretch, to slurp; To slop: perchance to strain: ay, there's the turd; For from that colonic what streams may come When we have shuffled off this toilet seat, Must give us pause: there's the digest That makes putridity of so long lunch; For who would bear the turds and scats of shrew, The oppossum's wrong, the proud man's constipation, The pangs of despatched sewage, from maw's delay, The insolence of orifice and the spurts That patient process of the foodstuff makes, When he himself might his flatus make With a bare bumkin? who would fartels bear, To grunt and sweat under a sweaty gut, But that the dread of something after lunch, The undiscover'd country to whose bum No excrement returns, puddles of swill And makes us rather eat those swills we have Than flies or beetles that we know not of? Thus hunger does make sheisters of us all; And thus the vile hue of poo solution Is sicklied o'er with the wormy cast of thought, And extrusions of great pith and moment With this regard their composts turn awry, And lose the form of Tootsie. - Soft from firm! The shrew Ophelia! Nymph, from thy orifice Be all my snacks deliver'd.
And thus, by theory new, dethroned this king's, or no, becomes a throne for other things.
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kain
Insignes
Posts: 144
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Post by kain on Mar 30, 2010 13:18:51 GMT -10
@sam: Hey, bad verse can be a hell of a lot of fun! And I will admit that bad rhyming verse is better than bad free verse almost invariably. Re: Pitchers Have there been studies comparing captured prey in a particular Nepenthes species over geographic range or one that compares prey items captured among (more than one) species in a particular locale? How about over altitudinal range within and among species? Arg! So many questions and so little ability to do the research myself! walterg: That is... amazing and terrible. My lauds to your new throne for Shakespeare.
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Post by leilani on Mar 31, 2010 23:48:42 GMT -10
Wow, I don't know what to say except "Bravo!". I've seen Hamlet's soliloquy abused in many many ways but nothing quite as disturbing as your work.
[Sorry, Sam, but I seem to have inadvertently deleted most of your post, by hitting the Modify button instead of the Reply button. I guess it was just a matter of time before I started abusing my super powers... - Walter]
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Post by walterg on Apr 1, 2010 3:48:39 GMT -10
Someday, when I know you better, I'll show you my Sonnets...
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Post by leilani on Jul 5, 2010 0:17:47 GMT -10
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Post by leilani on Aug 8, 2011 22:25:17 GMT -10
I had reason to revisit this thread today. I was considering sending the "Nepenthes Catch Insects to Lure Larger Prey" article to the BBC or whoever it was that just made a big deal about somebody's Nepenthes catching a bird. It turns out that, this time, I have better things to do. Still, I had forgotten just how much fun we had with this thread and parts of it are well worth reading again. For instance, take another look at Walter's "Hamlet"! Unfortunately, I'm pretty sure we also offended a few people. I'm sorry for that but, on the other hand, a gem like .... The shrew Ophelia! Nymph, from thy orifice Be all my snacks deliver'd don't come along every day.
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Dave Evans
Nobiles
dpevans_at_rci.rutgers.edu
Posts: 490
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Post by Dave Evans on Aug 9, 2011 5:42:20 GMT -10
Lets just take Sam's non-specific theory a step further, Nepenthes aren't really carnivorous as they just catch random things in motion. Based on the shapes, objects just get stuck without any intent present in design. That the plants gain from this is simply a coincidence that some of these objects contain nutrients.
How's that for a load of you know what?
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Post by peterhewitt on Aug 9, 2011 6:50:39 GMT -10
Or conversley....Nepenthes are totally Carnivorous, and are designed to catch anything catchable, in multiple modes of action. From poo, to the shrew itself.
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Dave Evans
Nobiles
dpevans_at_rci.rutgers.edu
Posts: 490
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Post by Dave Evans on Aug 9, 2011 12:21:29 GMT -10
No, it is just that the associations are plain as day. Species associations are just that; the co-evolution hasn't been that strong and many larger animals that have associations aren't symbionts--which is also clear as day.
Why does an animal have to feed at a pitcher in order for it to use it as a crapper? That is just the standard model for insect prey--clearly the mammals are co-opting to the plants for their own needs and behaviors.
People don't need dogs, yet there is a very strong association between humans and dogs.
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Post by dvg on Aug 10, 2011 13:43:49 GMT -10
I had reason to revisit this thread today. I was considering sending the "Nepenthes Catch Insects to Lure Larger Prey" article to the BBC or whoever it was that just made a big deal about somebody's Nepenthes catching a bird. It turns out that, this time, I have better things to do. Still, I had forgotten just how much fun we had with this thread and parts of it are well worth reading again. Reminiscing about the golden days of the forum were you? I recall birds being caught in your own Nepenthes pitchers and you even did a satiric spoof on the whole thing... Earthy News / March 4, 2010 / Pons Institute / Netherlands Nepenthes Use Insects to Bait for Bigger Prey Recent observation have revealed that a Nepenthes, large carnivorous plants from Asia, living in open environment in Hawaii attract and prey upon small birds known locally as Japanese white-eyes. These large plants attracts these birds by first luring and capturing insects. For years carnivorous plant enthusiasts believed this insect capture mechanism to be the primary function of the "Nepenthes Trap" or "pitcher". However, current studies now confirm that the insects captured supply only a tiny portion of the nitrogen these mysterious plants crave. The much greater reward for the plants comes after it has captured insects. It is believed that these amazing plants have evolved to use these captured insects not so much for the nutrition they provide but rather as a lure to attract even larger and more rewarding prey.
The mystery of these amazing "bird feeding" plants started to unwind when the authors of the study began recording their observations in the field. It seems that the devious Nepenthes, with its wickedly phallic pitcher appendage, captures small flying insects purposely in order to utilize them in an even more elaborate and diabolic scheme to capture the lovely little Japanese white-eye.
To quote one author ....
"It all became clear when I noticed that this particular species of bird was just the right size to perch on the rim of the pitcher, accommodated by a pitcher lid of just the right size and angle of reflex and a peristome that seem almost designed to the task. This "perch" gives the bird an advantageous position from which to view the pitcher contents. The opportunistic little insectivores are, of course, attracted to the small bounty of freshly captured insects floating on the surface of the pitcher fluid. Sooner or later the hungry bird can no longer resist the temptation of the free meal and will, head first, attempt to retrieve insects from the fluid."
This is where things get interesting.
"Once the bird enters the pitcher it is doomed". "Over millions of years of evolution the pitcher, or trap, of this amazing plant has evolved to become the perfect Japanese white-eye death trap. Once the bird enters it quickly finds that it can not back up. Inhibited by the slick walls of the pitcher and a formation known as the peristome the poor bird's fate is sealed and the diabolic Nepenthes will now slowly drown and consume its innocent victim."
The authors of these recent studies have backed their hypothesis on some very compelling numeric and nutritional studies.
"What struck me most was the coincidence of measurements." "The pitchers were exactly the right size to accommodate the birds both perched on the peristome and, more importantly, inside the pitcher." "Detailed measurement revealed that once the bird is inside the pitcher it just fits."
The fit is so exact that some have suggested a mutialistic evolution may be the only answer. The studies authors will not commit to that but do believe the two species are intimately connected.
"I mean .... what are the odds?" "You gotta bird AND you got a pitcher!" "AND, the bird fits perfectly inside the pitcher!"
Further studies clearly showed, by sophisticated analytical techniques, that those plants that captured birds derived a far greater amount of nutritional reward from their catch than those that did not.
The work of the author and his collaborators are expected to turn the world of carnivorous plants on its head. They conclude that as it is the nature of life to always maximize its rewards it is not surprising that the Nepenthes would adopt a scheme that reaches beyond the mere capture of insects and looks to the greater bounty to be found in feasting on our avian friends.
As one author says "It just makes sense!" "One bird is like a zillion mosquitoes!".
dvg
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