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Post by phissionkorps on Jul 23, 2007 23:46:35 GMT
Dave,
If you want, you can publish our conversation we've been having here, just take out the parts at the bottom where I was asking you about dangerousplants, since that doesn't really have to do with taxonomy.
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Clint
Full Member
Posts: 808
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Post by Clint on Jul 24, 2007 0:33:45 GMT
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Post by Dave Evans on Jul 24, 2007 15:25:42 GMT
Okay, I will try it out... Maybe the moderator would be able to change the authorship of your emails back to you after I post all the replies... (edit) Finished with this process of posting the conversation. Ron, I edited some of the relies a little to make things clearer to other people. Also, since this thread is more about the differences shown by N. tentaculata I stopped adding pieces of our conversion when it veered in to the Indochinese Nepenthes. I added a lot more information to the last post about genetics, so it would be a good idea to re-read it and pick it up from there... Readers: All these next posts say they are from me, but they are not. Please check the top line and you'll see who authored which email. Sorry if this is confusing, but I don't know how else to post the messages in a chronological order. Dave, If you want, you can publish our conversation we've been having here, just take out the parts at the bottom where I was asking you about dangerousplants, since that doesn't really have to do with taxonomy.
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Post by Dave Evans on Jul 24, 2007 15:28:40 GMT
Hello Phissionkorps, What makes a species? I thought it was having at least one special characteristic, not seen in close relatives. Not needing to closely examine a specimen to notice clear differences should be a help indicating where to draw the line... Please explain why you think N. tentaculata will sometimes show eye spots, and most populations do not. Hybridization is a logical method which might cause this to happen. F1 hybrids are not what I'm talking about here. Rather something which is more adaptable and successful than it's ancestors. I am not saying this is the reason, but a likely one and should be considered... Also, DNA doesn't always work the way you assume. Some alleles are attached to each other and so they do not get watered down. This can/could problems, as well as benefits in future generations. If one allele is promoted, another could "come along for the ride", it doesn't have to be useful, just it's neighboring stretch of DNA. The eye spots could be random, or they could be attached to another specific part of the DNA. Also, take the example of N. edwardsiana. It most certainly does appear to intermediate between N. villosa and N. reinwardtiana, in every single detail that I have observed. The simplest answer is usually the correct one... No? N. villosa is highly localized, N. reinwardtiana is ubiquitous. I think N. villosa has managed to evolve itself into an attitudinal dead end. It can no longer migrate downward due internal changes it had to make to colonize it's high altitude domain, but part of it's DNA might make the trip to new areas by mixing with the DNA of a more successful species. Does this really seem absurd or faulty? What are the flanges on the peristome for? I suspect they are used by the plants to collect mist as a controlled way of adding water to the pitchers. This seems like it would benefit epiphytic species, which need to collect water, but at the same time not dilute their digestive fluids. BTW, there are plenty of plants I have viewed which show hybrid characteristics. If you carefully examine plants in your collection, you might find a couple also. N. rafflesiana and N. ampullaria are great examples of this. Look at the baby pitchers when new basal rosettes form--you'll probably see intermediate characteristics on some of your 'pure species' plants. N. hamata and N. tentaculata are each other's closest relatives, I am not saying they are not. But by keeping them under that same name, we would be indicating a closer relationship than what has so far been seen. People theorize there are intermediate forms between N. hamata and N. tentaculata, but there are no records these exist. I'm sure they did at one time though, which seems to be in the past... N. maxima shows no real separation for it's many forms, even N. eymae appears to be a part of N. maxima. Also, there is no reason to suspect hybridization has not played a role in the diversity shown by N. maxima--especially regarding the lowland populations. N. alata is an other story. It grows with a couple of other species, depending on the location where it is found. I have no doubt hybridization with N. ventricosa in the northern areas of it's range and hybridization with N. copelandii in the southern end of its range have muddied the waters. Also, the name is sort of broken. The type specimen was destroyed so it is rather difficult to pin down exactly what the name is supposed to refer to. Several author have tried different methods of redefining the name, but for example, Danser made it worse by including N. eustachya into his definition N. alata--This continues to confuse people to this today. I have two plants called N. alata. I am pretty sure one of them is, but it is rather difficult say so with any certainty:
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Post by Dave Evans on Jul 24, 2007 15:36:47 GMT
From phissionkorps: Dave, I think that the making of a species should require it having more than just one different characteristic. If you have brown hair, and I have black hair, would that make us a different species? If your truncata doesn't have strong throat splotching, and mine has huge, dark, purple splotches...do we have different species then? Well if you're a splitter I guess so... I think assuming tentaculata has reinwardtiana DNA is faulty, but at the very least it is jumping to conclusions. Eyespots are apparent in so many species and hybrids that I feel we can no longer say "reinwardtiana = eyespots". One species that exhibits them is alata. Unfortunately I can not remember the entire list of species/hybrids that have displayed them, so if you are interested in that, its best to ask Leilani (Sam), or possibly Cantley. I've also seen reinwardtiana without eyespots, and I've seen reinwardtiana with 1 eyespot. I think its saying to much to assume that. I know what you're saying about linked genes (degree in biology with specialization in ecology and environmental biology...but theres no way you could've known that lol). I'm going to definitely have to dispute the fact that you say that linked genes do not get washed out. Of course they will...all genes will get washed out over time, especially if the F1 is crossed with tentaculata, and those progeny are cross with tentaculata, ad infinitum. Even in hybrids like (A x B) X B) that A is becoming quite washed out. Look at vent x clip x vent. Now imagine if there was a trait so small and insignificant as eyespots, not morphology or anything else, JUST eyespots in "A" (50% tent, 50% rein). Now if we go A x B x B x B x B x B x etc, you are decreasing the amount of reinwardtiana DNA to a negligible level after only a few generations. I think it would be goign much to far to say that one hybrid was made, and though generations later only .01% of the reinwardtiana DNA was still there...the eyespots remain. Seeing as eyespots have popped up in so many different things, they've either got to either be random, or a very ancestral piece of DNA that most if not all neps have. In your example of edwardsiana...I can't agree with until I can see some genetic proof. These are no longer the days of natural history, and therefore I'm skeptical to label relations in regards to anything without genetic proof. Morphology has not been the preferred method of distinguishing species since Linneaus. Occam's Razor is not always the best plan of action... Villlosa has a range of 2400-3200m. That's a pretty good range if you ask me. All the time people are finding plants out of the ranges originally reported by Danser, et al. I have some mira I grew from seed that grows at a constant 80°. Sure, its totally slow, but don't you think after breeding these plants together, etc, etc, there eventually would be a heat tolerant and pure mira? I don't think your hypothesis of villosa DNA hybridizing and getting to new areas seems absurd, I just don't think it seems plausible. Its two natural hybrids (that I know of) are harryana and kinabaluensis, in both of which, the other parent is also ultrahighland. For some reason I don't see villosa trying to make a trip downward. Very few other species have the same requirements, why would it want to move? While I find your theory about the flanges (do you mean the teeth?) interesting, there very weel could be a totally different explanation. Frogs have been known to lay eggs under villosa's peristome for protection...what's to say villosa did not co-evolve for this purpose? Like I said before, until I see some good genetic proof, the hairs on the lid and the different peristome are not enough to convince me that hamata is anything more than a geotype that warrants anything more than varietal designation. The differences between the two species are few and far between. If these are to remain separate, we might as well split alata, split maxima, split raff, etc. I think some alata forms, and most certainly some maxima forms deserve to be split more than hamata/tentaculata. For an interesting thread on comparison of maxima forms, please have a look at this: pitcherplants.proboards34.com/index.cgi?board=nepwild&action=display&thread=1184068030Please tell me how hamata and tentaculata are so different, but ALL of those pictures are of the same. exact. plant. Not even varietal status for the different maxima forms... Also, please see this thread for more on the tentaculata/hamata thing: pitcherplants.proboards34.com/index.cgi?board=hamata&action=display&thread=1146477595&page=1Hybridization certainly does play a role in speciation, but at some point its time to split a species off. I feel that maxima and alata are in a state of speciation, but it is too soon to declare hamata/tentaculata two totally different plants.
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Post by Dave Evans on Jul 24, 2007 15:40:22 GMT
Hello (don't know your name...) The first paragraph in the quote below is silly... No I'm not a splitter or a lumper. I follow evidence as it comes up. I don't have agenda or a belief system I have to adhere to. Also I don't recall saying there should not be subspecies or varieties in Nepenthes. Now I understand how one person might put more emphasis on one piece of evidence than another person might. The nature of living systems, indeed the entire world we live seems to be one in which complex systems grow and diverge. But it is not like there is a schedule to this, some species remain intact and fairly static while others form and go extinct. Species are a reproducing system of temporary individuals--none of them are "pure". I don't think DNA can get washed out (not without attrition of individuals before they have a chance to reproduce anyway), rather some future individuals will not have the same exact DNA of their closest relatives or their ancestors. This is why I don't look just like everyone else in my family, but I still look more like them than people from other parts of the world, since they branched off my family tree at an earlier time and have since undergone changes which helped keep their populations intact that my direct ancestors did not experience. And those changes were ridiculously small compared to changes needed to form another species of Homo. I think there must be a very good reason Nepenthes and Sarracenia have not developed stronger barriers to hybridization==> I.E. it is good for them to have such weak barriers as a whole. The eye spots shown by several species of Nepenthes appear to be gaps in the waxy layer. I rather doubt they are useful, but maybe insects are somehow attracted to them and this might serve as a way of continuing to promote their presence in Nepenthes. Or they are attached to a more useful set of genes and come as part of a set. I wonder about more colorful species, maybe they have eye spots too, but they are not noticeable to our eyes... BTW, I rather doubt all "species" are hybrids, but I really have no doubt that many individuals within a species have DNA from some of their neighboring species--not enough to call them hybrids, but enough to help them avoid inbreeding depression. I don't think N villosa "wants" to do anything, other than grow and reproduce. I suspect some its genes could be making a "migration" without intent thanks to chaos and general random motions of the insects which carried their pollen to another species instead to another N. villosa plant. Many species do have hairs on their lids, especially when they are seedlings. The "hairs" on hamata aren't even hairs, BTW but branched multicellular organs very similar to what you see on N. tentaculata and on baby pitchers of N. rafflesiana. I think these are an extension of the 'hairs' on the wings at the front of the pitchers. I do expect closest relatives to have more in common, especially regarding morphology. Please take a closer look at the way these two species grow. Very disparate. I think you might focusing on what they have in common and not noticing what makes them different. I don't know if DNA testing would provide proof one way or the other... Flanges ending in pointy teeth seems to be a recurring theme in highland and ultra highland species, this has developed in several distinct groups (lineages) of species within Nepenthes... There has got to be an ecological push toward developing this feature. I wonder what/why would be promoting this feature? Dave, I think that the making of a species should require it having more than just one different characteristic. If you have brown hair, and I have black hair, would that make us a different species? If your truncata doesn't have strong throat splotching, and mine has huge, dark, purple splotches...do we have different species then? Well if you're a splitter I guess so... I think assuming tentaculata has reinwardtiana DNA is faulty, but at the very least it is jumping to conclusions. Eye spots are apparent in so many species and hybrids that I feel we can no longer say "reinwardtiana = eye spots". One species that exhibits them is alata. Unfortunately I can not remember the entire list of species/hybrids that have displayed them, so if you are interested in that, its best to ask Leilani (Sam), or possibly Cantley. I've also seen reinwardtiana without eye spots, and I've seen reinwardtiana with 1 eye spot. I think its saying to much to assume that.
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Post by Dave Evans on Jul 24, 2007 15:55:37 GMT
From phissionkorps: Dave, Sometimes, on the eyespots, one will notice a buildup of nectar. A nectar droplet if you will. Cantley has hypothesized that since these droplets are already experiencing a maximum value of surface tension, once a bug touches them, the droplet more or less engulfs the bug and slides down into the pitcher. Interesting, but who can say if there is any basis in that being the purpose or not. They could just serve as markings to guide insects to that area, or have a different function alltogether. I to often wonder what the teeth are really for. In my experience, nature seems to not favor toothy peristomes. If you have time, please see this thread on the subject: pitcherplants.proboards34.com/index.cgi?board=general&action=display&thread=1184490077Regarding the hairs on the lid...all Nepenthes have these at the seedling stage, and every time I grow from seed I wonder what the point of them is. I think the hairs have become vestigial, but there are a few species that retain them. Why that is the case is another question. -Ron
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Post by Dave Evans on Jul 24, 2007 16:02:21 GMT
Hi Ron,
I read the thread, and I feel like I've been to the other side... The owl photos were great!
All species of Nepenthes are toothy, just in most the "teeth" don't end in sharp points nor do these ribs expand outward creating flanges, like what is seen in about ten species (which are not all closely related). I didn't see N. singalana mentioned once in the thread... I have not noticed any hybrid displaying characteristics indicating gene dominance or recessiveness.
Now, I just counted the number of "teeth" or ribs on both N. t. = 120 and N. h. = 40. Smaller pitchers have slightly fewer ribs, while larger pitchers tend to have a couple more on both species. What I found interesting was that even on the smaller pitchers, the numbers are close, just that the ribs are also smaller on the smaller pitchers of both species. Hmm...
The leaf attachment, there are about another ten species with the same type of leaf attachment. The species which shows this most strongly is N. adnata. The overall shape of the pitchers is very close, but more details that are reviewed the more different N. t. and N. h. appear.
I think the species have DNA which is mostly the same in Nepenthes. Even in humans, our DNA is 98% the same as that of our closest living relative, the orangutan. The differences we see between us and our closest relative appears to come from the way the DNA is arraigned and how it is used more than the actual genes present. The human genome project raised more questions than it asnwered. There isn't even a Nepenthes genome project so we are kind of stuck with very basic genetic studies at this point.
All Nepenthes have teeth, it is just their size and number which changes from species to species.
N. macrophylla appears to be rather intermediate between N. edwardsiana and N. lowii, BTW.
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Post by Dave Evans on Jul 24, 2007 16:08:44 GMT
From phissionkorps:
Dave,
You know what would be awesome? If someone would finally get down to business and start working on nep genetics. I have been involved in so many conversations about what is related to what, when what diverged, blah blah blah that I can't even count that high. What is unfortunate, is that you have your opinions, and I have mine (I'm sure we differ on other species as well), but these conversations are forced into stalwarts for the time being. To be honest, I'd be the first to admit I was wrong if someone could prove it genetically, but then I'm sure we would argue about what % change in DNA constitutes a new species . Such is science. In terms of the tentaculata/hamata thing, I don't know why rsivertson hasn't chimed in yet. He would probably have a lot more solid information than I do. Here's a post I found from him on this forum from March:
"Well, glider, I have! Even John Turnbull, who formally defined the plant, admitted to me that "except for the peristome, it's just another N. tentaculata". Other species such as N. rafflesiana, N. maxima, and N. mirabilis all have some very different geo-forms unique to the specific locales in which they grow, some with very different peristomes, and botanically, the extreme developments of the peritome alone is questionable as a botanically significant enough feature to warrant separate species status, and may be better classified as a sub, or geotype form of N. tentaculata. Nonetheless, it does occupy a very specific, and isolated and unique area and form solitary populations; the same holds for N. ephippiata, which is very closely related to N. lowii, and may be just another geotype form, it even has the bristles under the vaulted lid, but the pitcher is not as constricted, (ventricose) as the other geo forms of N. lowii on the other mountains within the Crocker mountain chain. It could be attributable to simple genetic drift, or possibly gene pool contamination, in which some other species is involved. "
And according to Michael Catalani: "N. hamata is very closely related to N. tentaculata. Once you get beyond the spikes of N. hamata, the plants are very similar."
Whether or not its enough of a difference to warrant species status depends on who you ask. There are certainly species of Nepenthes that are so similar that they would simply be forms or variants of each other if the same criteria for elevating Sarracenia to species status was applied to Nepenthes. "
Out of curiosity, how do you feel about N. tenax? Do you feel that it is just something split of mirabilis, or that it's its own species? What about rowaniae?
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Post by Dave Evans on Jul 24, 2007 16:14:02 GMT
Hi Ron,
Re: N. tenax and N. rowanae.
I have not seen either species and have no opinion. I am just glad to see more research is being done in Nepenthes especially by very good scientists, like Clarke and Lee, among others with a lot of experience in Nepenthes. Since these folks can concentrate on the pitcher plants, instead of just dabbling, I think their findings are more likely to be thorough and be less flawed than some of what we have seen in the past.
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Post by Dave Evans on Jul 24, 2007 16:19:09 GMT
Hi Ron,
Actually, Rich has been to my place a couple of times and we have had several long discussions about this very same subject. While different populations of animals have their own culture they pass onto their young by example, plants cannot do this. While morphology is very important, so is behavior when discussing plants. This is one of the main reasons I think it is kind of funny that some people want to combine N. hamata back into N. tentaculata. There is no evidence to suggest N. hamata will ever "re-combine" with other populations of N. tentaculata, which actually also occur on the same mountain(s), but at lower altitudes. I would buy into the idea they are the same thing if N. tentaculata regularly "turns into" N. hamata throughout the rest of its immense range. There are plenty of opportunities for it to do so, yet this doesn't happen. Why? If they are so close as to be placed under the same name, then the same conditions ought also induce N. tentaculata to take on the form more similar to that displayed by N. hamata as it colonizes very tall montane environments, yet there is no evidence this occurs, even when it colonizes areas that high.
When I mentioned this idea to Rich, he said he never thought about this way and would have to think about it... I haven't discussed this with him for several weeks now.
On the other hand, maybe there is something special about Gunung Lumut... The species N. eymae is very, very similar to N. maxima. And no, N. tentaculata is no where near as variable as N. m.. N. t. seems to be much more stable in the characteristics it shows, even though its range is larger. I think it will take a lot of research to figure out why this is the case. Hybridization could be playing a role regarding N. maxima's extreme diversity, but maybe not... N. hamata seems more likely to have evolved more directly from pre-N. tentaculata.
While Turnbull and Middleton said it is basically very similar to N. t. they did name it as a species and so did Kurata (under the name N. dentata (I think). These people didn't name it as a species for no reason.
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Post by Dave Evans on Jul 24, 2007 16:34:19 GMT
From phissionkorps:
Dave,
But then wouldn't calling hamata a "geotype" of tentaculata cover this? Phenotype = genotype + environment. Expressivity and penetrance are both affected by environment. What's to say that they do not have the same exact genes, but some are expressed more actively in hamata? I wouldn't discount that theory, because something is obviously making hamata display the hairs on the top of the lid.
Think of this example: black races are black because of their environment. Their genes coding for melanin (exactly the same as all other races have) are just more strongly expressed in order to shield them from the beating-down sun of Africa. Now, if I moved to Africa, I wouldn't suddenly become black, and if I moved to Africa and had a baby with a white women, who in turn mated with a white person and so on, my lineage would not just happen to pop out black one day. I'm sure due to that environment, it would eventually happen, but after how many 10s of thousands of years? All races are still classified as Homo sapien ssp. sapien because we share 99.95-99.99% similar DNA (we also share 96-98% similarity with the great apes...but thats a different story). Its obvious that hamata and tentaculata share the vast majority or their DNA, or its exactly the same, but expressed differently. They're either each others closest and very recently diverged ancestor, or they're 2 forms of the same thing.
Why would tentaculata and hamata not recombine? Hamata is found from 1400m-2500m, and tentaculata has apparently been reported to be found at 700m-2550m...that puts it at a higher range than hamata itself. Surely there is going to be some cross-breeding and subsequent washing out of genes in both directions. Obviously hybridization plays a large role in speciation, but I just feel it's too soon to separate the two. What it seems like, and correct me if I'm wrong, but it seems as if you are saying that since we can't see the change occur, they're different. I think quite the contrary. Maybe a timely stretch 10,000 years ago, the environment hamata is found in had an abundance or reduction of oxygen. Maybe the sun shone brighter on that side of the hill for a while, I don't know. But I don't think we should be saying things like, "just because we haven't witnessed either inter convert, it isn't possible".
Do you know anything about the flowers of the two? Admittedly, I do not, but it would be nice to get a comparison of the two. Info on seed pod morphology, seeds, etc, would also be nice.
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Post by Dave Evans on Jul 24, 2007 17:20:59 GMT
Hi Ron, Hmm... Well that is my point. We don't have any evidence this is what is happening. Almost none. Apparently, there are some examples of N. hamata which don't have large flanges, but they can still be identified as N. h. based on other characteristics--Cheek and Jebb mention these might be hybrids between the two, but they can't tell one way or the other without doing field research. It doesn't seem like it is the environment causing N. tentaculata to behave or respond differently. But it certainly could be the case and we are not able to perceive it. Several scientists have visited the locations for both species and none of them report seeing anything other than two different species. I haven't been there and I think your theory is completely plausible, but all the evidence provided by the people gathering data points in the other direction. All Nepenthes are very close, the shape and function of the various parts is about the same in nearly all species. Only a couple of species diverge dramatically from the norm. The same can be said of Pinguicula. It actually has taken quite a bit of effort on my part just to get people I have been talking with in the hobby to notice details about their plants that do not involve focusing solely on the pitchers themselves. I am happy you have quite an open mind about them. Makes for good conversation. I don't know if N. fusca should be considered a part of N. maxima, they both have freaken huge numbers of populations in their own right. One thing that is certain, they will not be interbreeding without human intervention, so for now, without nature changing dramatically (which can indeed happen) they are on separate paths. And they sure do seem like they are in the process of becoming more different. Other species, like N. mirabilis and N. ampullaria have even larger ranges, but these seem more stable, meaning they are already well adapted. This doesn't mean they aren't collecting mutations, they most certainly are. However, while there are some individuals which deviate, sometimes dramatically, from the norm, the environment isn't selecting for them--yet--at least not in anyway we have been able to notice. The comparison to people is limited. After you and your white woman move to Africa, you both would have to start a lineage with literally tens of thousands of descendants which in turn magically do not mix with the locals. Even if the original sample of the new Africans was larger than just two people, the environment would have to be killing off the lighter toned children at a higher rate than darker children in your lineage or there wouldn't be any push for the population to respond to. It would have to be a rather delicate balance too. If the attrition rate was too high, inbreeding depression would rear its ugly head among the survivors--they would have to mix with the more genetically diverse locals or face likely extinction due to their weakened state and constant competition from other humans groups. Too low and we are talking a very, very long time indeed with minimal change. BTW, all the genetic evidence to date shows that Asian and European races are tiny sub-sets of the much larger African genetic pool. It was the lighter tones races which adapted to the different climate. Also very recently discovered is that with in one stretch of DNA, there are multiple copies of the same gene. Hypothetically: Africans might have five or six copies in a row of the gene that codes to make human skin pigment or even, say, collagen. Whereas other lighter toned races could have fewer copies along the same stretch of DNA. Each time a skin cell runs that part of the DNA for protein production different amounts would be produced, depending on the number of copies, by the same exact process. Genetic analysis tests we have will not show this difference because they work by multiplying the original sample for comparison looking for differences in coding (base pairs spelling changes--a much more drastic change). Differences in the structure or arrangement are basically invisible to these tests and new ones have to be developed to fully understand this adaptive nature of DNA. Not sure if this smaller kind of genetic difference would account for differences we see between N. hamata and N. tentaculata. About the "hairs" on the lids. If you look at the wings on the front of the pitchers of N. hamata, they too tend to branch in three directions, just as those on the tops of the lids. It would seem the same genetic change affected both areas. In N. t. I only see this on a couple of hairs near the spur. My plants are still fairly small though, what do poeple see on their large plants? N. lowii and N. ephippeata. We have evidence N. lowii has changed to attract a certain type of prey. Whereas less research has been done with N. e., it still doesn't seem to have developed the same diet. I think it might be better to create groups of species which would fall under several sub-genera, instead of combining species back together as subspecies. This could make for some good graduate work, with more experienced researchers working on the new finds.
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tonyc
Full Member
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Post by tonyc on Jul 27, 2007 12:55:34 GMT
Cndncp, here's another form of tentaculata. It's the speckled one that used to be available from Malesiana Tropicals: Does anyone have location data for it? Cheers, T.
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Post by agustinfranco on Jul 27, 2007 22:05:40 GMT
Hi all: Very interesting theories about the origin of species. IMO, tentaculata and hamata are different species regardless their looks and yes, they share similar genes. There is no black and white but large sections of gray when it comes to speciation and hybridization. At some point in time thousand years ago? there were hybrid populations between a toothy species and tentaculata with a hybrid in between called prototype hamata. The toothy species was extinguished and the tentaculata parent with the prototype hamata remained alive. At some point in time the prototype hamata exerts its "locking mechanism" as i call it and voilaa we get what we called hamatas nowadays. As evidence for this theory is the fact that the hairy hamata as we call it, share certain characteristics with the typical form buy it does have a different pitcher shape, colour, lid, and hairs Again, these questions come on board very often as to what we call a hybrid and what we call a species. The example I always give is when a stable hybrid population becomes a species or it remains a hybrid. Is it the extinction of parent plant A or B or both? or crossing a male and female plant from the presumptive hybrid would yield a plant that looks 99% identical to the hybrid parents?. From that moment on, it'd become a species? If there is a locking mechanism which separate 2 species or a hybrid from a parent species, when is this activated? are there genes which stabilizes the containment of certain characteristics or is it just geographical isolation of a particular group of plants which allows these to be called species? Gus
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