Reptile & Amphibian Forums

The picture that I posted earlier was of a yellow vent and not a red one- I just happen to like that picture. Plus, I am told that it is one of my frogs (through a trade). Anyway, going by "morph" is very dangerous because the morphological species concept is not widely accepted. If it were, than people with red hair would be a different species, which is ludicrous. What one must understand is that genetic data in this area is very poor and that all of these (lamasi, imitator, ventrimaculatus, amazonicus, etc.) may be the same species. Everything that I have read points to the fact that amazonicus=ventrimaculatus. The different colors may just represent different populations. I have also gotten my yellow vents to turn more of an orange and almost red color through the use of paprika. To make matters even worse, I have heard of hybrids of vents with reticulatus and fantasticus.... who are thought to also be close relatives. All of that may be hearsay though b/c I can't find the source. At any rate, only more genetic data can tell us the truth.
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Justin
stk18119@loki.stockton.edu

D.auratus
D.leucomelas
D.tinctorius (lorenzo, yellowback, citro, pb, oyopock,etc.)
D.azureus
D.ventrimaculatus (yellow/gold)
D.pumilio (blue jeans, solid red)
P.aurotaenia (narrow bands/green)
P.bicolor
E.tricolor (Santa Isabel)
H. leucophyllata
P. hypochondrialis azurea
P. resinfictrix
etc.......

Hi,

All that I was saying was that the frog in the picture was more commonly refered to as D. lamasi and sould not be called a vent for clarity. Did you buy your frogs as D. imitator panguana or what? I am trying to aquire all the morphs of lamasi so if this frog is in some way different than the panguana morph I would be interested to know that. Also it dose seem strange that a picture of an american frog appeared on an international website under the panguana name if it was only a yellow vent. It is possible however that lamasi=ventrimaculatus so who knows...

Alexander Stubbs

This is not an American frog as you assume. It is actually a German bloodline. I have a few friends in Germany and also some in Japan- currently doing research on the pet trade. You would be suprised at how many American bloodlines make it overseas. I can see how one would see this as a Panguana vent due to the lack of the "Y" and presence of the stripes; however, I guarantee you that it is a yellow vent that has a similar pattern. Unless, I was lied to by my friend.

Bull! People may be mis-using the names and mis-representing their frogs, but the species are differet. Different occurrences, different calls, different ecology, different feet!

I don't know anytihng about frogs, but I know that if you breed them and they produce viable offspring, they are the same species. Someone should try it....just to put it to bed
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Matt

Hi,

I am not sure this is true. For example a lion and a tiger can breed and produce healthy offspring but they are considered different.

From what I have read....not much!, ligers and tigons are usually sterile with a very rare instance of fertile offspring...same can happen with a mule. I believe that males are always sterile, with the rare fertile offspring always being female. Anything is possible I guess.
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Matt

>>From what I have read....not much!, ligers and tigons are usually sterile with a very rare instance of fertile offspring...same can happen with a mule. I believe that males are always sterile, with the rare fertile offspring always being female. Anything is possible I guess.
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>>Matt

lions ligers, tigons, and the fav hybrid of the day the bengal.
im not sure with the big cats as much as the bengal breed
but when the breed was first being produced the first 3 generations of male where steril. but after that they are fertil, the females are always fertil. to get the next generations you either cross the hybrid with either species untill you get a fertil male, typicaly this being a f. catus
being thata f.bengalesis would make a cat closer to the wild type (i have an evil f5 and can only imagin how a earlier generation can be)

just a thought

ashley
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Just A Thought
Ashley
;P

np
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Matt

no
i own a bengal
it is a cross between a F.catus and a F.bengalensis
or in simple no taxon
a domestic cat and a asian leopard cat
so no tiger but the genetics for the bengal and the tiger/ lion hybrids are the same
or not the same, but in the after a few generations the males will become fertil, and the females are always fertil

ashley
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Just A Thought
Ashley
;P

np
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Matt

>>np
>>-----
>>Matt
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Just A Thought
Ashley
;P

::

.

Different species can and do interbreed, that is no longer a "litmus test" for classification as a species. Patrick

I haven't done much research of dendrobatid specie differentials, but I do know this; under the Biological Species Definition: if two organisms can propagate and yield sexually-viable young, then they are, in fact, the same species. Locality-dependent characteristics such as calls and foot shape don't distinguish a species. If the frogs can produce young that have the ability to propagate, then you just have two different "morphs" of the same species.
On the other hand, under the Specific Mate Recognition System, species are defined by the physical characteristics particular to that "morph". This idea, has been under fire in the last decade, and seems to be undergoing a "fading out" process at the university level.
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Randy

Hi,

I quite frankly do not understand how you could mistake a vent for a lamasi. They are different in size and behaviour. My panguana lamasi are very different from my amazonicus and I do not understand how they could become confused. I have just consulted my copy copy of R. shulte's book and it seems that there are differences in the throat pattern between amazonicus and ventrimaculatus (there may be differnces in the call but I do not red german). Also lamasi is eaven placed in a different species group (d. vanzolinii).

Alexander Stubbs

Again, differences in throat pattern mean just that- not necessarily same or different species.
Genetic data, in which Schultze does not have (that book is outdated by the way and his theories have no support and are not taken seriously by the scientific community).
I basically am saying that amazonicus= red vent. They have been shown to be almost identical in karyotype and can interbreed producing viable offspring. Amazonicus is not even recognized as a species by the AMNH
I agree, Lamasi do have slightly different behaviours than vents; however, peruvian vents (panguanas) not only look similar to lamasi's but also have more similar behaviours. Maybe what we
are seeing is a slow progressive split from one species to another- lamasi to vent or vice versa. Just a thought.

I doubt very seriously that any one who has ever kept and bred any ventrimaculatus group frog, (that is a frog that lays lots of small eggs at the edge of water, to name one distinguishing characteristic) would confuse them with "imitator group" frogs, such as reticulatus, imitators, fantasticus, or intermedius, which all lay smaller clutches of larger eggs, adhered to leaves or the glass.
It certainly seems clear to me that this breeding ecology is likely a dividing line between those two groups of frogs, among other things, as mentioned by Chuck. Such a difference would most likely also rule out the possibility of hybridizing them. Patrick

you right...I forget the name, but one way in which speciation occurs is differences in habitat within an environment...say if one group preferred grasslands and another inhabited swamps(I am not talking about frogs necessarily), another type of speciation occurs because of differing breeding seasons(spring or fall), and the third way speciation occurrs is due to a physical barrier(mountain range, river). When enough time and generations have passed, and the two groups of animals will no longer breed together due to psychological reasons(wrong coloration), or physical incompatibility(different number of chromosomes, speciation has occurred and the two groups of animals may be considered different species. These are generalizations and not the end all be all test. There are exceptions, and human intervention often confuses mother nature.
Anyway, I know I am not going to settle this. I also know that I don't know enough about frogs yet to even prticipate in this thread so I will keep my mouth shut from here on out
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Matt

Sorry guys, but the majority of the scientific community has a strict criterion that MUST be met before two groups of organisms can be cosidered two different species:

"A species is a group of organisms that are able to interbreed successfully, producing offspring who themselves can reproduce with an individual of either group. When one group of organisms can no longer breed successfully with another group, then those two groups are considered to be different species. There are several reasons that prevent successful breeding, but one condition must be met before those barriers can be erected, REPRODUCTIVE ISOLATION."

You are correct in that geographical isolation can lead to differences in behaviors or reproductive cues (vocal call, for instance) which have the possibility of leading to a new species, but these differences MUST create icompatibility between the two organisms. If the barrier separating the two groups were to be removed and the two groups remained reproductively isolated from one another, then you have an instance of allopatric speciation.

The earlier exerpt is taken directly from a graduate biology book of mine "Molecular Evolution and Phylogenetics" by Barry G. Hall and is the book of choice by my graduate professor of Genetic Variation at the University of Kansas.
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Randy

Randy,

No offense, but your definition and apparent understanding of speciation is more simplistic than reality dictates. Because the speciation concept is nothing more than a man-created classification system operating on a conglomeration of models and theories, it really cannot be isolated to the simple offspring viability test.

In the grand scheme of things taxonomists are generically divided into two groups (another man-made conceptual imposition): the lumpers and the splitters. It seems you ascribe to the former. If you insist upon using your rule universally that as you progress toward more "primitive" organisms you are going to start seeing two organisms which are commonly considered separate species which will, per your definition, have to be one and the same species.

Unfortunately, reality does not always fit into our man-made constructs. Naturally, my explanation is cursory and simplistic as well, but I think you'll find that further reading by other authors will show you that the theory you have vocalized is certainly not the "end all to be all" final word on speciation.
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Homer W. Faucett III, esq.
Purveyor of Trivialities and Fine Nonsense

Hey Homer,
Absolutely no offense taken, however, the arguement here seems to be "what is a species"? We are all inherently shackled to the limitations of our human constructs, and lo and behold, even our contemporary concepts of phylogenies aren't safe from question. This is how our understandings of the natural world are shaped, we test and test until we find a constant, and then we test this constant some more, continually amending the constant until we have a scientific construct (which can only be disproven, never proven).
As of now, most forerunners in the evolutionary field are standing beside the methods of speciation I touched on before(emphasis on touched). Some of these leaders include Dr. David Ackerly, head of Ecology and Evolution at Stanford, as well as , Dr. Richard Michod of Duke, both which have contributed an insurmountable amount of data to this very question "what is a species".
Our man-made, humanly-inadequate idea of "what is a species" is just that, an idea. The modern definition of "species" in any current, peer-reviewed evolutionary text will state that reproductive isolation must be present.

>> "your definition and apparent understanding of speciation is more simplistic than reality dictates."
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Randy

(continued from last post)
"I apologize for the length of this letter, but I didn't have time to make it shorter." -- Mark Twain

I'm a student, so I've got the time
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Randy

If the sole are going to rely solely on reproductive isolation, then you have to determine exactly what is meant by that--do you mean mechanical isolation, genetic isolation, or geographic isolation (note that over enough time the first and last usally equate to the second).

Further, such a reliance simply on reproductive isolation seems to fail to take into account the realities of conjugation that happen not only between species, but families and genera in the "lower" kingdoms. It seems to me that phenotypic or morphological traits have to be recognized at some level before they become so divergent that sexual reproduction is no longer possible. Indeed, even genetic variation can be substantial before sexual reproduction is impossible.

I suppose that I could accept the sexual isolation term of speciation for what it is . . . an attempt to objectify the slippery concept of speciation, but it really does not solve the problem of identifying and preserving genetic variance, differentiation, and preservation. Instead, those issues are just pushed farther down the Linnaen tree, where they must still be dealt with. Additionally, the problem this presents with species preservation is that current regulation regarding protection of endangered organisms operates on the species level. While that could change, legislative action is typically slow (as are some of those to administer them) . . . I wonder what type of effect this would have on the status of some animals, which are currently considered separate species, should they be lumped together into a larger group (and, presumably, population) of animals as one species under this sexual isolation theory.

It just seems that this is a potentially dangerous and, ultimately, unfruitful taxonomic construct built for the sake of objectify one level of classification only to complicate the further levels of classification.

Just my thought,
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Homer W. Faucett III, esq.
Purveyor of Trivialities and Fine Nonsense

If the question was about preserving genetic variance, that's fine, keep members of similar phenotypes, behavior, etc. together in the same group. But this was not a question of whether or not we should preserve the morph, it was a question of whether or not two species can produce viable offspring.
You mentioned mechanical isolation, genetic isolation, and geographic isolation. Let's define each: M.I. is an incompatibility in structure of the male and female sex organs. Genetic isolation means that a group has become so genetically divergent from their parent group, that they have become sexually incompatible*. Geographic isolation just means that a group has become separated from its parent group by a mountain, lake, etc.
Geographic isolation is nothing more than one of the means to the end product---reproductive isolation. If a group is isolated for long enough, then that group may diverge from the parent groups' genotypic character depending upon selection factors of their respective environment. Some of these selection forces may result in mechanical isolation, which means that they are reproductively incompatible or ISOLATED.
We haven't mentioned other possibilities that may lead to reproductive isolation....what about mutation? Gene flow? Genetic drift? All of these mechanisms can attribute to the final product of reproductive isolation. According to contemporary scientific terminology, reproductive isolation must be present in order for a group of organisms to be deemed an independent species. I can throw references out all day long... but who would read 'em?
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Randy

Randy,

I understand the terminology I use, if you are just clarifying for others, that is fine. However, your post was unresponsive to my two points, which are fair criticisms of the definition of speciation you vehemently support by reference, but not logic: 1) the simplification of the definition of speciation may allow the easier objectification of what exactly comprises a species, but you still have to sort out the other variations in classification below the species line . . . so what does that accomplish, other than pushing the difficult decisions below the species line? Secondly (2), how do you defend this sexual isolation definition of species in light of the several "lower" organisms wich can exchage genetic material through conjugation or other means, despite extreme morphological (and genetic, for that matter) differences which have previously caused such organisms to be divided into different genera, not just different species. At that point, your definition of a species seems tenuous at best, as conjugation is usually considered a type of sexual reproduction which can occur between different species.

However, no model is going to be perfect, and the model you bring up is quite clean but for these outliers. Nonetheless, it still seems far better suited for animals than lower level organisms.
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Homer W. Faucett III, esq.
Purveyor of Trivialities and Fine Nonsense

I suppose let's first let's touch on this: "...your definition of a species seems tenuous at best". Unfortunately, I can't claim this definition for myself. It's the overwhelmingly supported definition of animal classification by the scientific community. I use references in my arguement because, well, we wouldn't know as much about the environment around us as we would if it weren't for research. Referring to that very research is only logical.
I defined the mechanisms earlier for you (and others) to see that these, as well as the other mechanisms I mentioned, are just means to an end result--reproductive isolation. I've no doubt that you know the meaning of the terms, however, it seems as though you've neglected the way these mechanisms fit into the grader scheme.
As for the "lower" organisms, microbes conjugate and don't breed with one another, so reproductive isolation isn't applicable. The construct holds true for kindom animalia (for now).
"...but you still have to sort out the other variations in classification below the species line . . . so what does that accomplish, other than pushing the difficult decisions below the species line?" What difficult decisions? If you suggest classifying by morphology then you are asking for trouble. For instance, if a 6-foot tall, 200-pound, blonde-haired, blue-eyed caucasian wants to wed and father children with a 4-foot tall, black-haired, brown-eyed, web-footed Baku pygmy from Southeastern Cameroon--- no problem. Despite their very large phenotypic differences, they and their children are still 100% homo sapien.

You're right, this stuff's slippery. The best we can do is to try and get a firm grip on some of the ideas and simplify them as much as possible. Hopefully, someday someone will stumble on a grand unified theory and put an end to these debates.
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Randy

Randy,

My "tenuous at best" comment seems improper in retrospect. I didn't mean for that to be condescending, but it sure looks that way now that I re-read it. I really enjoyed hashing this out with you, and I have half of a mind to check out some of the primary literature if it's really progressing in the way you have described. It just strikes me as an odd trend which may have to be re-evaluated. But then again, maybe I'm missing a valuable reason for adopting this concept (other than making a litmus test available for speciation). Thanks for exploring this issue with me, as you've been quite collegial in this reparte.
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Homer W. Faucett III, esq.
Purveyor of Trivialities and Fine Nonsense

Hey Homer, I didn't take that as condescending, this was all in good spirit and I enjoyed it very much as well. I wish every thread could elucidate differing perspectives as much as this one. I suppose I feel as though I must adamantly defend what they're teaching me in school, so that I can at least say that I got my dollar's worth. Thanks agian for the symbiotic exchange of ideas.
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Randy