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kadakuda

Define a specie.

Question

i come from more of an animal education (herpetology) but it seems that plant taxonomy is a WAY bigger mess than much of animal classification.

i know what officially defines species, sort of (lol), but what should actually declare separations and clumping?

seems to me with all the rules set out to define a specie is so commonly broken so many times. so. ya, is it even possible to use the current system for classifying, at least plants, species?

the binomial system is cool and rather useful in many ways, but it seems rather inadequate in so many other ways. for a very obvious single point: hybrids and reproduction.

is it even possible to, probably cant ever use this work in a realistic context here, *properly* distinguish different plants from each other in a ___________ system?

some use morphology, others reproduction, others chemistry, others the effects they have when taken (medicines and poisons), or perhaps all or a couple together.

seems some groups, Echinopsis, prove much of the "rules" for distinction wrong or invalid.....OR..... the current classification is wrong and perhaps things like astrophytum and lophophora are the same specie cause they have been hybridized, for example. or maybe this whole binomial system is flawed from the get go?

anyway, just curious. maybe they're dumb q's, i think stupid random things when i drink sometimes :wacko:

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I don't really know the answer to your question, but I believe that the singular is still species, not specie. Anyway, I always though that two different lifeforms are considered not of the same species when they cannot produce fertile offspring. Can a bridgesii x pachanoi produce viable seed with another plant? If so, then my definition does not hold for Trichocereus species.

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I would argue something along the lines that a species is whatever the most accepted student of the specific taxon claims it is at the time, as clearly there are far too many discrepancies to say there are real laws regarding classification.

Check out these two wiki pages for just a taste of the problem:

http://en.wikipedia.org/wiki/Species

http://en.wikipedia.org/wiki/Species_problem

~Michael~

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They are not stupid questions. If you can come up with a rigorous scientific answer then you've got one of the biggest scientific papers of this decade and an instant professorship.

As you've pointed out, approaches to the problem differ from your perspective (eg. plants vs animals) and I think the way taxonomists approach the problem differs from that of the horticulturalist. Taxonomists are typically not concerned in the great degree of taxonomic noise we create through breeding and hybridization. Horticulturalists have identified the shortfalls of the binomial system for their purposes and add an extra epithet for the cultivar name.

Echinopsis is a mess and the only real way to sort it out right now would be a high resolution phylogeny built on molecular data. In plants, taxonomic boundaries today are typically drawn on genetic difference measured at the molecular scale as well as morphology and geography.

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The problem with this concept in plants is any definition will have arbitrary aspects since it is humans defining not just the characteristics for ranking them but also whether said characteristics are trivial or meaningful.

I've asked a few PhD botanists this question and all have nearly laughed and told me its a good question.

No one had an answer as it is more of a political process than a scientific one -- at least as it stands presently.

I mentioned to Myron Kimnach the zoological view of what defines a species and he was almost incredulous.

Its really twisted right now in that it is not uncommon to learn that NO ONE can determine who actually does the renamings of something specific without having to directly ask David Hunt and get a reply from him.

Its not worth spending much time worrying over since the movers and shakers have no apparent desire to see this get turned into a science.

The good-ol'-boy mentality literally rules the day.

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Since species don't exist outside of a context there is no definition that can be applied in a consistant manner.

The concept of a species is more key than the definition of it, but we cannot escape the fact that our taxonomy is an artifice.

That being said I can offer context based definitions, if a specific context is mentioned.

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the good-ol'-boy mentality literally rules the day.

This seems to be what science is in manifestation, despite all it is in theory.

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Since species don't exist outside of a context there is no definition that can be applied in a consistant manner.

The concept of a species is more key than the definition of it, but we cannot escape the fact that our taxonomy is an artifice.

That being said I can offer context based definitions, if a specific context is mentioned.

How about you simply provide for us a "specific context" to make your point and offer us all a "context based definition" of what a species is? Enough beating around the bush already.

~Michael~

Edited by M S Smith

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As you wish.

In a cactus context two forms distinct to seperate isolated populations sharing a common ancestral population can be termed seperate species in relation to a descriptive account even when no biological barriers to reproduction exist. The foundation of this recognition of distinction is based upon obvious morphological and physical differences that prevent general misidentification of one species for another. This relates to the concept of a species having the function of identification as opposed to documentation alone. This is important because we employ the nomenclature to identify and utilize plants ergo binomial nomenclature is the foundation of western cultural ethnobotany. It is the function of making distinctions in relation to utility that informs what concept of species is effective in providing that utility.

There is no benefit to using a species definition employed well in the research of vertebrates when it fails to provide the user of the definition with enough distinction to identify, study and or otherwise functionally relate to cacti. This is why contexts inform species definitions as opposed to species definitions informing contexts via the imposition of a standardized format which may not always be capable of providing the function that is at the foundation of the system in the first place.

If we define species in cacti according to their inability to breed and produce fertile offspring then we have the problem of considering many plants that are distinct in form, habit, chemistry and utility etc as a single species. This is the case with many opuntia and echinopsis forms which if considered myriad forms of a single species creates greater confusion in relation to the the study and observation of these plants.

To give a broad definition of a specie:

A specie is functional term specific to the account of identifiably distinct populations of alleles having the following properties:

1 The population has been and can be consitantly identified to the point of distinction from other species and specimens.

2 The population is fertile and stable in regards to heredity for the given range of alleles to the point that exchanges and recombinations of alleles with other populations (if possible) produce specimens that can be identified as outside of the normal range of alleles as they violate the first property.

A specie can be considered a standardized symbol whose refferential application to a consistant phenomena facilitates a functional relationship between the subject employing said symbol and the given phenomena. In the case of biology the symbol takes the format of the specific epithets of binomial nomenclature, however a specie can be considered conceptually to apply to phenomena outside of the realm of taxonomy and thus the term (specie) may be found in contexts outside of biology.

Edited by Archaea

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Species are based on:

...biological (ability to produce fertile offspring)

...morphological (especially, but not restricted to, reproductive organs)

...geographical (this is a large part in botany... in plants biological species concept breaks down due to complexity of reproduction, ie the fact that plants can produce fertile offspring even when considered different species, therefore sometimes distinct niches of very similar plants can be considered different species, or even possibly sub species only because they grow in distinct habitats)

...and biochemical/genetic (this is a fairly recent addition to plant taxonomy and has been able to separate species further into more species and also more sub species... although the plants are practically identical, the fact that they have distinct biochemical signatures, or distinct genetic alleles can cause them to be considered separate entities)

so in short a species in botany is defined by how much research is based around a plant... in general alot of what we consider species today will be totally torn apart and re-arranged by the botanists of the next generation... its what keeps us botanists in a job...

it really depends on whether someone is interested enough, has enough patience, and can get the funding (or is just a rich bastard) that limits the depth as to how we will classify all plants on the planet!

ohh... and im pretty sure species singularly is still species... never specie

Edited by Mr Stay Puft

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Archaea, I get what you are saying, though having to dig through the verbosity about three times, but its all been said before in simpler terms. Sure, our words for the plants don't fit the plants themselves, and the "elite" control the application of language to plants...yeah, we get it, but what sort of proposals exists that are acceptable to you, or what is your own proposal?

~Michael~

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Archaea, I get what you are saying...

I gave you the contexts you asked for.

First a cactus specific context, second the allele based organismal context and third the context of specie(s) as an element of terminology beyond biology. I would write the same thing in AP style which is dumbed down for average levels of litteracy, but it would not be as concept dense and would take more time and space.

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I take it you brought this thread froward again as you want it to continue..

I gave you the contexts you asked for.

First a cactus specific context, second the allele based organismal context and third the context of specie(s) as an element of terminology beyond biology. I would write the same thing in AP style which is dumbed down for average levels of litteracy, but it would not be as concept dense and would take more time and space.

Yes, you had provided part of what I asked for, but not all, as you hadn't answered by question regarding "what sort of proposals exists that are acceptable to you, or what is your own proposal?" No only has this been asked by me, but by kt on at least two occasions I can think of.

Mr Stay Puft, seeing that you said "its what keeps us botanists in a job" I'm going to assume you are a botanist of some degree, but even should you not be I am more than a bit curious about your take on Archaea's comments.

~Michael~

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The one key missing element is that there is no indication of how said "cactus specific content" is proposed to be created.

The details of that will make or break this otherwise sound suggestion. If prior descriptions are not useful what is?

One thing worth keeping in mind is the notion of a static and stable species is just not real. Its just a human idea we are using to try and make sense out of what can be observed within the narrow window containing our life spans and the duration of our cultures.

Its something for the here and now only. 10,000 years forward or backward there is no guarantee said species will have exactly the same range of values.

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KT, the idea of a stable atom is over time subject to the same problem, everything in the universe is ephemeral, even the universe itself.

I am not saying prior descriptions are invalid, but perhaps another analogy can be used.

Why not call today by the same name of the week we used the day before?

The week itself, as you point out for cacti, is artificial.

However there is the concept of now that can be applied.

We need only deal with extant forms, if our system for the days of the week was incapable of accounting for a new day we would have the same problems with it that we have in taxonomy.

The days of the week continue to be used but they fit the dynamic procession of planetary cycle. Populations too involve a dynamic cycle but the static taxonomy is incapable of dealing with change without revision.

I am not rejecting any past accounts, but rather the basis of my assertion is the same as the observation here:

Its something for the here and now only. 10,000 years forward or backward there is no guarantee said species will have exactly the same range of values.

You are addressing how the dynamic aspect of nature cannot be described by our static nomenclature system. You may be satisfied with a description that is effective for you for the duration of your life, but I want one that is a little more objective.

Now consider, if you will, that in every extant population a basis for their morphological expression exists in the form of a dynamic code with a static foundation of nucleotides. Nature itself uses a static alphabet to express dynamic fluctuation, however it has evolved criteria that inform the process and needless to say it is not consensus based. Likewise it is incapable of going out of date or failing it's contextual function. Is it so absurd to suggest that we too can employ a taxonomic method that is criteria based and capable of functioning for the description and identification of populations, that is capable of accounting for dynamic fluctuations without re-defining the species every time said fluctuation results in increased divergence and morphological distinction?

Plants don't reject and redefine their genes because phenotypes change, change occurs and alleles are conserved.

When taxonomy was founded the concepts behind it were very different than modern concepts now employed. At the foundation of the system was a static view of species, the concept that god created species and they never changed was the foundation of the system we employ to this day. I am saying we have come far enough to know that the static species concept is rather inextricable from taxonomy.

When you describe species as in a state of gradual allelic flux you describe species as they are in nature, species on paper are static as they are currently represented.

if we were to revise taxonomy I would suggest that the foundation needs to be the recognition of the natural dynamic state which we obviously agree exists. I'd write more but I need to change a diaper...

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I take it you brought this thread froward again as you want it to continue..

I posted here by mistake and deleted it, ergo it wasn't a intended bump.

Yes, you had provided part of what I asked for, but not all, as you hadn't answered by question regarding "what sort of proposals exists that are acceptable to you, or what is your own proposal?"

That is true.

Archaea, I get what you are saying, though having to dig through the verbosity about three times, but its all been said before in simpler terms. Sure, our words for the plants don't fit the plants themselves, and the "elite" control the application of language to plants...yeah, we get it, but what sort of proposals exists that are acceptable to you, or what is your own proposal?

You don't get what I am saying Mr. Smith.

Since you misunderstand me I am at a loss to be able to address what you mean in terms of proposal. How can I have a proposal relative to what you think I am saying when you are wrong about what I am saying? I cannot give you an honest answer because the question isn't specific enough to do so. Likewise with your antagonistic behavior I doubt the sincerity of your question, which seems provocative as opposed to being representative of wanting to consider what I have to offer in terms of said proposal.

I can let you know right now however that the species concepts I employ are beyond the context of any single discipline, thus they will not be the same as those of classic botany, but they will not contradict the classic definitions which are many in number.

The word specie is both plural and singular BTW, it is a word that exists outside of specific epithets, thus to define a specie goes far beyond biology.

One online source claimed the word specie can be translated from latin to mean "in it's actual form"

Edited by Archaea

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Honestly, regardless of whatever misunderstanding you think I have in your words, or whatever antagonism you may read into them, I am sincerely looking for you to propose an alternative view to the current definition of species which you find faulty as it is not helpful for me to reject the current system which provides us the ability to maintain discussion about these plants without having a replacement.

Archaea, earlier you said that you could "write the same thing in AP style which is dumbed down for average levels of litteracy, but it would not be as concept dense and would take more time and space." If you want to be understood a little better maybe you should take a little consideration of you audience and dumb it down for us average people, even if it takes more time and space. I know I would appreciate it.

~Michael~

Edited by M S Smith

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I am sincerely looking for you to propose an alternative view to the current definition of species which you find faulty as it is not helpful for me to reject the current system which provides us the ability to maintain discussion about these plants without having a replacement.

My definition of species in this thread should meet the requirements you state. Here it is again.

A specie is functional term specific to the account of identifiably distinct populations of alleles having the following properties:

1 The population has been and can be consistently identified to the point of distinction from other species and specimens.

2 The population is fertile and stable in regards to heredity for the given range of alleles to the point that exchanges and recombinations of alleles with other populations (if possible) produce specimens that can be identified as outside of the normal range of alleles as they violate the first property.

You understand that giving a species definition doesn't reject any system of taxonomy. Nor does it confuse discussion about the plants. All my definition above means, in terms of pachanoi lets say, is that T pachanoi is an epithet corresponding to population(s) that can be identified consistently as T pachanoi to the point of not being confused with other species. Also it must meet the second requirement, ergo normal reproduction of the population results in the species as can be identified per requirement 1.

The definition does imply that pachanoi and it's allies are unwarranted as distinct species given known descriptions. Since each species has its own specific range of variation the criteria for delineating differences in form, as opposed to species is species subjective. I would propose a non-consensus model based on allele stability. Don't conflate this stability with a lack of change over time, rather this stability is what allows change, ergo it pertains to the alleles which are stable in each population. Show me a population where alleles aren't hereditary if the concept of stability in this contexts seems to undermine this validity of the concept.

If you want to be understood a little better maybe you should take a little consideration of your audience and dumb it down for us average people, even if it takes more time and space.

Thanks for the advice!

I write to be understood by those who can understand my writing. I'll laughingly admit I hope there is someone out there aside from me who can read it but at the same time it is not my habit to compromise my writing by tailoring it for a specific audience. I am verbose, that is accurate as hell. I am not trying to convince, but rather to represent, (yo!)

I am sure my thoughts, as well as my words, are atypical for average humans.

Maybe I am writing for the atypical minority?

I'd rather not write from inside the box if you catch my drift... the obfuscation of nomenclature can discourage those who would not benefit from reading my writing anyway.

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Where is this data going to come from?

It sure would be nice if it was available but I suspect the simple logistics of data acquisition may defeat your proposal? More power to you if you actually can do this.

Just achieving element 1 where "The population has been and can be consistently identified to the point of distinction from other species and specimens" would be a phenomenal feat and contribution even if for only a single species much less the many thousands of taxa that are known in the wild and will need this data generated.

One thing that would be hugely helpful to aid people understanding your words are to say what you mean rather than using allusion instead of details. The above post was a nice move in that direction.

Thanks for posting it.

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In an ideal situation the system would employ molecular data and bio-informatics to generate data.

There is no reason to throw out the old data, but there is good reason to transition away from specific aspects of the taxonomic methods that undermine the ability of the system to account for dynamic change.

I do regret that to do this right requires advanced AI...

We can even conserve the binomial epithets, but there need to be other symbolic tag like referential numbers (hexidecimal?) to allow data manipulation.

This is all hypothetical though. I'd never undertake such a vast revision as a hobby, I cannot find the time or resources I would require.

I'd look to codon variations for initial data mining and move from there. If I undertook such an effort I'd want to reconcile viruses, phages and mycoplasmas with bacteria (and archaea) with multicellular life. The programs being used to provide data comparisons in bioinformatics have variable criteria settings that could be subjectively employed for the establishment of probabilistic relationships in terms of phylogenetic symbolism. It would be far better to have a serial number next to an epithet than a name. Science needs to be depersonalized to protect it from the egos of us all, including myself.

Edited by Archaea

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Archaea

First of all, I'd have to say that what you're thinking about is very worthwhile, and I think you're attacking it from the currently most viable angle, that is the evolutionary species concept with a dose of the genetic species concept. But as you'd be well aware of, this is a problem of interminable difficulty.

"A specie is functional term specific to the account of identifiably distinct populations of alleles having the following properties:

1 The population has been and can be consistently identified to the point of distinction from other species and specimens.

2 The population is fertile and stable in regards to heredity for the given range of alleles to the point that exchanges and recombinations of alleles with other populations (if possible) produce specimens that can be identified as outside of the normal range of alleles as they violate the first property. "

I see problems for this in terms of the line between "population" and "species". Populations, as subunits of what we currently understand as species, have a measureable range of allelic variation at any one point in time. Furthermore, this range of allelic variation can and does differ between populations.

So consider two independent populations, recently geographically separated, and suppose we artificially exchange one individual between the populations and mating occurs. Suppose this individual from pop 2 happened to be carrying alleles outside of the "normal range" of alleles for population 1, then the population 1/2 hybrid offspring inheriting those alleles from that mating event would then be "identified as outside the normal range of alleles" of pop 1 and therefore, according to your species definition, our two populations must be considered seperate species.

The way around this is to prescribe the "range of allelic variation" unique to a good "species" to encompass this variation within and between populations. In this case we suffer from a problem of degree and gradation and tend to circularity. An artificial line must be drawn to determine what are populations and what are species and we violate our own law at one scale to uphold it at another.

In fact, I just had a thought that your conditions would actually mean that ANY population subdivision would almost by definition create a species boundary. If I cut a population in two, so that they had no way of reproducing with each other in the coming generations (it only need be temporary) then as our population goes from one to two, given reasonable genetic diversity and a large population size, genetic drift or "sampling error" would create two different, observable, definable ranges of alleleic variation for the two now separate pops. If I remove the barrier, interbreeding now produces offspring outside the normal range of both populations separately, but within the range of the ancestral, undivided population.

If there's one question as difficult as "What's a species?", it must be "What's a population?"

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I do agree its great in principle but I'm still not clear where the data is going to come from?

A person needs solid plants to start with and a thorough study of what is out there to be meaningful.

I wish you success in seeing this become real but I have concerns about its reality in application.

Just trying to scare up the money for simple gc-ms can be a bitch if several samples are involved, the work you are describing is going to require a lot of coordinated and meticulous collection input from a lot of field workers and a budget for labwork that might exceed the GNP of a fair number of nations.

I'd like to think it could be made real but there are some nontrivial hurdles to overcome before it can start.

One of the most substantial would be a through enough field survey to enable to rest of the work to start.

More power to you if you can pull it off.

I do not have a lot of confidence in the actual viability of it actually becoming a real world project for at least three reasons (adequate genetic data acquisition, the extent and depth of requisite labwork and the level of funding needed for both phases of the project) but I would certainly offer whatever support I could for seeing it be tackled.

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I think that with the tools we have available at the present moment a combination of flower morphology, areole morphology and geographical distributions in defining species in the Echinopsis genus.

Of course molecular data would be the be all and end all but until someone comes up with the backing to undertake such detail research we must use what we have to describe the cacti that we observe.

As many of us have these cacti in cultivation in our backyards... a long way from their natural habitats we must rely on flower and areole... as well as over all habit and rib shape to describe the species of plants that we collect.

There is no point preaching about what should be while none of us have the means to better the research in this area... maybe a number of us who have a background in botany, genetics, biochemistry and photogarphy should think about collaborating over the next few years... hopefully with some outside funding (maybe a little hopeful here) and publish some literature to make sense of what i believe at the moment is a lot of here say and misrepresentation..

To start with we should collect data on what we now consider species... specifics of flower and areole morphology.... and try interpret this data into some useful information....

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I do agree its great in principle but I'm still not clear where the data is going to come from?

Is the world so lacking in data?

even the act of rejection builds upon the foundation of the previous

I do not understand why what data we have must be thrown out. Isn't this what you are saying? We cannot use data if we don't like the paradigm it was obtained under?

If anything KT i feel like you over complicate some things.

Sure more data will be collected, but there are a lot of nucleotide sequences recorded for many species already and there are many protein sequence records too, there is enough to begin correlating codon wobble language and protein conservation/nucleotide conservation. Without proteins it is much harder, but proteins are like the new phenotype trait thing.

A major part of this is that humans can't do it, they aren't fit to contrast the data, it requires computational technology even for determining study and data collection methodology in a pragmatic way. Humans would only screw this up with their damned lack of objectivity.

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Edited by trucha

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