Species: structure and dynamics

Here I look at this sluggish current discussion, and I am amazed at how much forum members are exposed to troll... I ignored the topic myself, because more than half of it is trollism, less than half is nonsense, and the topic itself is a clear provocation.

How can we discuss the problem of the species "in entomology"? Having created a topic with this name, the author of the topic already puts entomologists at the very bottom of biological science, towering over us like a sort of pahan, doyen, great father, who descended to entomologists from the heights of Real Biology. I hasten to disappoint the author: the concept of a species is a general biological problem, and not a narrowly entomological, theriological or botanical one. A highly specialized definition of a species ("a species in the genus Colias is a yellow or red four-winged horseradish that flies in the mountains or on the plains at such a speed that it is difficult for my decrepit body to chase it... blah blah blah") can not be by definition - and this is the main problem: biodiversity is so large that it is simply impossible to describe its minimum unit in some universal criteria.

Defining a species is not the prerogative of any science, but the prerogative of the concept of studying it. There was a morphological concept - there was a morphological definition ("a species is a collection of individuals..."), there was a population concept - the corresponding population concept ("a species is a collection of populations..."). Phylogenetic, philosophical, molecular, phenetic, and so on, so on, so on. And in all concepts - in a considerable number of varieties, sometimes very, very different. And there is nothing to be surprised - who eats a girl, he dances her.

amara, I've been thinking about how to make a less confusing statement about what I would like to understand about the "view". I will not say that I have an idea of the current main stream of knowledge, but I am familiar with the generally accepted concepts at least at the university level
That is, it is quite clear to me that in modern biology, a species is a necessary concept that actually exists.
So, this is how I imagine it - for people who are not very experienced in biology, the concept of a species is most often associated with a specific individual, that is, here is a butterfly-turnip that sits on a flower - this is the type of "turnip".
However, if you get a little familiar with modern biology, it turns out that a species is a "collection of individuals" with all sorts of reservations. And here is the "most interesting" part.
I don't know what the author of the topic wanted to express, but he successfully created the topic - insects are famous for their metamorphosis, and an individual of the same species can occupy completely different econ-niches, look different and have completely different anatomy. In general, give a caterpillar and a butterfly of the same species to an inexperienced person, but "a little familiar" with general biology, he recognizes in this not only different species, but different types.
Here, let's imagine a certain "genealogical tree" of diurnal butterfly species, where the imago will be the type individual of the species. Everything will be very clearly visible - a lot of external morphological differences.
Now, as a typical individual, let's take a caterpillar. There are also a lot of differences, but somehow it is not so full.
And if you take a zygote as a typical individual, then in general everything will be "one egg".
Now we can imagine that the huge qualitative and quantitative differences between species that are visible in the imaginal stages seem to collapse as ontogenesis reverses and almost disappear in the egg stage. Zygotes have almost the same shape, almost the same biochemistry, almost the same chemical composition, both quantitative and qualitative, in short, everything is almost the same, but at the gene level there are differences, and then, quantitative differences.

Thus, all this diversity of species, and their shapes, colors, and sizes, in the very essence, represents a certain numerically expressed difference in the structure of the genetic apparatus(+epigenetic factors).
And if we ignore the anatomy and morphology, and present this "digital" picture, then within the best species there will also be numerical differences among individuals, and if you virtually mix two similar species, will it then be easy to distinguish them in this mixture (no anotomy or morphology is visible) by these "root-cause " digital differences?
In general, it turns out that here the boundaries of the view are lost, and there is just a continuous series with small numerical differences. Here it is somewhere like this.

(page 599, third paragraph from the top):
http://books.google.co.uk/books?id=nhIl7e6...epage&q&f=false
by the way, the page is not displayed. And about the fact that the species can be represented as a single individual, I also adhere to similar ideas, but "without fanaticism", that is, there are some similarities, and only.

PS
By the way, I often spoke as a" fan " of molecular taxonomy, and in an extreme form, that is, without taking into account anatomy and morphology, and even more so ecogeography. However, from what I have written, it seems to follow that using only molecular data, it is not possible to develop a clear criterion for drawing species boundaries, since at this (genetic) level, species simply do not exist. Species characteristics should be formed in the process of ontogenesis and interaction with the external environment. But on the other hand, if there is such a technology that would provide a complete scan of the genetic apparatus and have a mat. a device that allows you to "calculate" the final result of ontogenesis based on this scan - no problem. Everything just again rests on the generally accepted single concept of the species, even if taking into account the anatomy and morphology. And even it is not there yet. But even here everything is solved - you can enter all these 22 concepts into the system, or 26, or how many of them there are, and output the result for each of them

and if you sort of virtually mix two closely related species, will it then be easy to distinguish them in this mixture by these "root-cause" digital differences?
In general, it turns out that here the boundaries of the view are lost, and there is just a continuous series with small numerical differences.

It differs very easily and precisely "in the structure of the genetic apparatus" in 97% of cases (for the already studied groups and territories), and no continuous series is obtained. The remaining 3% are either pseudovids and therefore do not differ, or there are special mechanisms that ensure this - for example, intragression. If you are going to discuss special issues, then read more special literature, not fiction.

Yes, well, just these percentages are fiction.
Distinguishing species by the "structure of the genetic apparatus" in most cases makes it possible to compare them. I actually wrote a little bit about something else. You have written all this so highly, but in fact it is obvious, for this you do not need to compare "apparatuses", it is enough to compare veins or genitals.
Because we are not talking about methods for determining a species from DNA, comparing it with the established database for already known species, but about methods for identifying species as categories based on DNA.

That is, let's say they brought you samples of different animals from planet X, in the form of just a DNA sequence. You need to use them to distinguish and describe the types from scratch. Here is such And such, this example is not entirely correct, since we are talking about the numerical equivalent, which is completely determined.

  
Because we are not talking about methods for determining a species from DNA, comparing it with the established database for already known species, but about methods for identifying species as categories based on DNA.

So it is clear that you are familiar with the problem only from fiction. Consequently, further discussion will not be possible.
And in general, the topic started delusional, no less delusional is developing (right rhopalocera.com), unprofessional maxims abound, and, in general, in the current format, the topic does not arouse any interest.

This post was edited by bora - 02/15/2011 18: 36

bora, it seems that you are an expert in the field of molecular phylogeny. It's very simple, I'm familiar with the topic of "fiction", and I ask experts, for example, "molecular" definition of a species?
Well, or at least the main methods of molecular phylogeny, which are now generally recognized?

And I did, but ka kraz on page 599 it was written that the limit to this page was exceeded. And there was no 598 at all. I even read the bottom page with a decent effort, but I'm still trained in languages, but it's bad, oh bad.

Now, in essence, the concept of the view.

PS
Yes, what is it, at the heart of the forum-glucoproteins? If it is not possible, then the message will not be sent, or the limit is exceeded..

amara, so from my philosophical discussions about the reality of the species, the discussion smoothly moved to a more pragmatic plane, about the possibility of molecular phylogeny. I have repeatedly written that I "believe" in molecular phylogeny, "believe" - because, of course, I do not have special knowledge that allows me to judge its capabilities.
It is just logical that it is better to classify by the root cause, and not by its" reflection", which is the phenotype. So modern methods and the level of technology are interesting.
That's why I want to know if there are already any hints of a "molecular concept of a species" that is suitable, say, for a university lecture, and not for specialists?
I am also interested in the possibility of predicting speciation based on the current theory of evolution and molecular taxonomy, with the definition of a possible phenotype of a species that should arise, say, in 10,000 years.

By the way, another argument in favor of the" reality " of a species could be given as follows: the fact is that the "phylogenetic tree" is actually a kind of tree-like cone, or pyramid, with its top rushing into the past, and its base standing on a "given moment in time", and this base is precisely specific species(but more precisely, after all - specific individuals). All other"branches" that go back to their origins are virtual. As an example of such a cone can serve as your own illustration about the elephant divergence, well located

But, here's the interesting thing - in addition to the branches that represent phylogeny in time, and unite species with their ancestors, there are also branches that unite individuals into a species at a "given time".
So, are these branches real? Why should they be real if the ancestral branches are virtual? After all, these branches define the very essence of the species - they are virtual connections, even if they are built according to specific characteristics. After all, each individual is not physically tied to another individual of its own species. I hope that I wrote it clearly....

Damn, I still had to draw, I looked for a suitable pyramid - no)))

Pictures:

hghhjhkj.jpg — (139.35к)

rhopalocera.com - on the general problem of the species in biology, I do not take a swing, this is a problem for you. I didn't single out entomology. For ordinary people in general, the concept of an insect is often indistinguishable from spiders and millipedes.

amara, thank you for the interesting explanations, I will answer a little later about the connections based on the phenotype, I will immediately say that I do not agree to replace them.

In the meantime, I found such a topic(carefully, the name!!!), the original article is attached to it, I have such a question on it - can this article be considered as a reflection of the achievements of modern mol. phylogeny?
http://molbiol.ru/forums/index.php?showtopic=449051

amara, thank you for the interesting explanations, I will answer a little later about the connections based on the phenotype, I will immediately say that I do not agree to replace them.

Few things disagree, but let's ask these animals themselves if they want to

are they these "virtual connections based on phenotype"?

They say ," we need to mate with individuals of our own species and avoid individuals

another, so that the offspring are fertile to leave, such are our tasks" and this

mixing says "and cements all our individuals into a single whole."

a continuous field, not individual points, and this is the flow field we use

we move in time as a single branch separated from other branches", and up to

speculative theories, such as associations by morphotypes, such as

Plato's Ides, they don't care.

This post was edited by amara - 02/16/2011 15: 48

You're all beating around the bush here. And there is pre-and post-zygotic isolation.

You're all beating around the bush here. And there is pre-and post-zygotic isolation.

These are details or details that have not yet been reached.

It is important for me to explain, and not just to one person, that a biological species is a real thing in nature, such as hibernation, and not a speculative theory that can be recognized or not recognized.

I'm sorry that I got involved in educational activities.
Just 10 sentences can be replaced with one word.

I'm sorry that I got involved in educational activities.
Just 10 sentences can be replaced with one word.

For those "who are in the tank" - yes.

So, since there are no comments about the article, you can take this silence for an answer, however, the answer is in that topic.
Minute of silence on the episode of mol. phylogeny )))

Now about the concept of a view. First, about philosophy.
amara, here you are comparing the reality of the species with the reality of hibernation, and this is inadequate. Hibernation is a process that is observed in a particular individual. What does the view have to do with it?
The concept of a species is entirely a philosophical category, and the approach to it should be like this. But not out of touch with reality and current biological trends, of course. Any science in general is basically a philosophy. Such are the cases.

There is no cementing on mating, there are specific individuals, each individual interacts with the environment, and other individuals for it are also the environment, for each element of the environment the organism has its own program, including the mating program. This all applies to logical connections implemented through the nervous system, and not through rigid physical laws. Without mating, the individual will not die. This is a logical connection, which is the most "soft" of all the others. If an individual stops eating, it will die before its biological time. If it stops mating, it will die on time, or even later than the population average (the "burden of motherhood").
It is true that the species will "die" if everyone stops doing this work, but this does not mean that these connections necessary to maintain the existence of the species in time are rigid and real, necessary for individuals. These are logical connections. Similarly, a view is a logical, virtual construct.
By the way, the word "virtual" does not mean - not existing, or ghostly. It means something like "capable of exerting power." such are the cases.

Now, we're sort of talking by default about organisms that have a sexual process, and only a sexual process. Insects reproduce only by the sexual process. Just in case, I will write that parthenogenesis in various forms is also a kind of sexual process. And what to do with plants that are characterized by both sexual and vegetative methods in different combinations?
A collection of plants that is separate from each other(the connecting shoots, for example, are rotten), but is a vegetative derivative of one individual, is this a collection of individuals of a species, or is it one individual of a species,or what is it? And there are plants that do not reproduce sexually at all, they just forgot how to do it. I'm talking about flowering plants by the way, there are such populations there. How to deal with them in the light of the reproductive concept? How are they related?

Following the central, superficial dogmas is convenient for exams and party meetings If there were no discussions about their essence, then there would be no true concept of the species.

And what does this have to do with the types of reproductive isolation, I don't understand, it is clear that in some cases, despite the "mechanical rep. isolation" (such as does not fit), you can stick it in forcibly, and sometimes you can even stick it out.. and get the posterity. Quite viable. But what does this prove? Only that the "species" is trying to create reproductive isolation by all available means. Because without it, it would simply disband, since it has no real basis.

"A view is a reality, a form of being."
I'm sorry amara, but in my opinion, this is also a 'fundamentally incorrect statement'.

To begin with, the term "Species" is part of zoological nomenclature, which is not a science. In nomenclature, it means" rank " of a taxon. Taxon rank is a completely artificial (i.e. not natural) category. But the rank of a Species is usually distinguished and given special properties, because this concept has a biological justification.

What is "biological justification"? This is a scientific theory.
The concept of "Species "is part of a scientific theory that explains the diversity of facts, and not the fact itself, given to us in sensations. I.e., the concept of" Species " itself should be considered as a scientific theory of its existence. A scientific theory cannot be definitively true, and in general the truth of a scientific theory is never confirmed. If we are talking about a scientific theory, and not a religious one, then at present the criterion of scientific validity is considered to be K. Popper's principle of falsifiability, according to which only that theory can be scientific, which is formulated in such a way that it presupposes the possibility of refutation. A theory is considered true as long and to the extent that it is not refuted. Also, every element of a scientific theory must meet this requirement. In addition, each scientific theory is formulated for a specific subject area, a narrow part of it, or a set of special conditions. Therefore, in different aspects and in different subject areas, a scientific theory can be correct and incorrect at the same time!

The species criteria are formulated in a general way for biology, but they either do not work or are not applicable within its individual sections due to the complete absence of the criteria used. Thus, the formulated general theory is incorrect or not applicable in particular cases. For each narrow area where the general definition does not work, a different type definition is formulated. Therefore, a view is not an absolute category, but a relative one. In this case, how can it exist without the subject who formulated it and without the subject area for which it is formulated?

Therefore, in my opinion, to deny or recognize the statement about the reality of the existence of a species, it is necessary to specify the scope of the subject area.

You say that species live in nature by themselves, without knowing about the concept of "species" and without agreeing. ok. Live! But not species, but specimens, individuals, which for a scientific theory are facts that the theory explains and unites, and not elements of the theory. I.e., the facts themselves lie outside the theory, they (individuals), sorry for the taftology, are factual, not theoretical.

I can agree that specific Species actually live in nature, if we consider a specific species as a set(in the mathematical sense) of individuals that meet the formulated criteria, a set of traits in a broad sense (including relationships).

In this case, absolutely any set that is defined based on the characteristics of real objects exists in nature. But of course, not every set reflects the sequence of subsets ' divisions over time, i.e., phylogeny. I'm talking about super-specific categories that you don't recognize as existing in nature, but for some reason you do recognize the species...

In ponapisalal! now I will get under the distribution, in full.

This post was edited by Seneka - 27.01.2012 11: 57

Seneka, what a distribution, almost no one needs such discussions here, and those who need them have already said everything
Let's talk about believe/disbelieve

In my humble opinion, there are actually populations in nature (despite the fact that the boundaries between them are not always definable and not always clear). A view is an abstraction created by a person for their own convenience. That is why its criteria work with such problems: In many ways, they are not a reflection of objective reality, but the result of agreements (both spontaneous and conscious).

With populations, too, not everything is simple (the most problematic situation here is when there is no sexual reproduction with recombination) - but in their case, there is a more or less objective criterion - this is the presence of a common gene pool that maintains its integrity and unity through recombination, ensures the existence of a single metaphenotype (a system of individual phenotypes interacting in a regular way) and evolves as a single the whole. As for the "abstract" species , what do an Arcto-Alpine plant from the high mountains of the Alps and a similar plant from the Siberian tundra have in common, except that the taxonomist considers them to belong to the same species? Yes, it is possible that they can potentially be interbred and even have fertile offspring. But in fact, they, for example, have no chance of naturally exchanging genes due to geographical separation. Moreover, for example, differences in photoperiodic reactions make even a potentially representable area merger (for example, in the case of a new ice age) possible only under the condition of strict selection - that is, changes in gene pools, and therefore an act of microevolution.

I think it would be much more interesting to talk about population boundaries and volumes, including complex cases. Although taxonomists may not be interested in this for everyone.

This post was edited by PVOzerski - 28.01.2012 12: 47

As for the "abstract" species , what do an Arcto-Alpine plant from the high mountains of the Alps and a similar plant from the Siberian tundra have in common, except that the taxonomist considers them to belong to the same species? Yes, it is possible that they can potentially be interbred and even have fertile offspring. But in fact, they, for example, have no chance of naturally exchanging genes due to geographical separation.

what do a Mongolian shepherd from the foothills of the Mongolian Altai and a similar Native American girl from the Amazon jungle have in common, other than that the taxonomist considers them to belong to the same species? Yes, it is possible that they can potentially be interbred and even have fertile offspring. But in fact, they, for example, have no chance of naturally exchanging genes due to geographical separation.
Is it silly to say that they belong to the same species?
Okay, now they have at least a theoretical opportunity to meet, and a thousand and a half years ago they did not have the opportunity to meet and exchange genes.
You can't say that they belonged to the same species?

In humans, the range is almost continuous (even in pre-technological epochs, the same Bering Strait was not an insurmountable barrier - which, in fact, is proved by the phenotypic and genetic similarity of American Indians with Asian Mongoloids). But if different groups of a reasonable person had time to live longer in isolation, they would probably fall apart into several species. As a matter of fact, this process has already been started - otherwise there would be no ras. But the great and small migrations of peoples interrupted this process many times. So I didn't like the human example.

Oh! I came up with a definition of the form
A species is a consequence of such a state of a group of individuals, in which the circulation of genetic material in their group is uniform, equidistributed in time and space. The degree of intensity and depth of these distributions characterizes the" quality " of the view(good view, or bad view).

All, this is my definition of the form

I'm afraid that doesn't happen at all. You have obtained a characteristic of an ideal "Mendelian" population, not a species. Even real populations are divided into so-called demes.

"I'm afraid this doesn't happen at all. "

Well, I talked about this here earlier and I don't agree that it doesn't happen. My definition has "gaps"

Well, let it happen sometimes . But then you will have the overwhelming majority of views that are "bad". And still, it will not be species, but populations.

Yes, they will be "bad", but this reflects the reality - in nature there are very rarely extremes - clearly limited populations, where conditions are perfectly uniform within the borders-there are probably very few of them.
That's why I wrote earlier here-the view is just a point of view that arose when looking at, how should I put it, one frame from a long film, which those who use this concept have not seen from the beginning, and will not see the end.

But a population is a system of individuals that actually interact with each other, even though its boundaries are unclear. And the view?

In humans, the range is almost continuous (even in pre-technological epochs, the same Bering Strait was not an insurmountable barrier - which, in fact, is proved by the phenotypic and genetic similarity of American Indians with Asian Mongoloids). But if different groups of a reasonable person had time to live longer in isolation, they would probably fall apart into several species. As a matter of fact, this process has already been started - otherwise there would be no ras. But the great and small migrations of peoples interrupted this process many times. So I didn't like the human example.

Isolated from each other populations that was dofiga. Just like in your example with plants. And yet one view. Even the Aborigines of Australia, who were isolated from other populations for tens of thousands of years.

You see, the criterion of interbreeding and obtaining fertile offspring, when carefully considered, does not formally work, even in the best cases for which this criterion was invented.

Interbreeding and progeny are actual events, not hypothetical situations.
The theory should predict the presence of such actual events. That is, by applying the definition of a species to a specific population and making a sample, we should get a set of facts that meet the definition.

Let's see what actually happens.

We take a sample from nature. There are several males(among them there are some who have not mated), several unfertilized females, several fertilized females.

We consider the criterion of the form strictly formally, i.e. literally.

To meet the species criterion, in this sample, all males had to breed with all females. This, as we can see, was not the case. Besides, even if it was, only one of the members of the group would become a father. At best, some of the males have interbred with some of the females. Bachelors didn't interbreed... None of the individuals in the sample produced fertile offspring.
I'm not even talking about the fact that females can't breed with females, and males with males, although I've seen such attempts on deer beetles, but there will be no offspring from such sex.

Further. None of the specimens in the sample interbred with their mother / father and are unlikely to interbreed with their offspring, because time travel is not available for them.

It turns out that applying the criterion of interbreeding and progeny, we did not find a single case that satisfies the conditions in the strict sense... We found only a set of individuals.

It was me

But a population is a system of individuals that actually interact with each other, even though its boundaries are unclear. And the view?

What kind of system is this? In reality, there are only independent pairs of individuals interbreeding(often only once) and separate individuals in a single population at a given time. There are no other sexual relations among them that ensure the integrity of the population. The most frequent interaction between them is competition, sometimes in the form of cannibalism. What interactions, where is the system??

This post was edited by Seneka - 28.01.2012 14: 55

Oh! I came up with a definition of the form
A species is a consequence of such a state of a group of individuals, in which the circulation of genetic material in their group is uniform, equidistributed in time and space. The degree of intensity and depth of these distributions characterizes the" quality " of the view(good view, or bad view).

That's it, this is my definition of the view

Commendable, a new definition! I liked "The view is a consequence" (well, yes, as a result, the ICZN was invented), "the state of a group of individuals in time" (taxonomists or something?), "circulation of genetic material in a group"(sho so directly and "circulation"? Roundabout traffic? ), "genetic material is evenly distributed in space and time"(DNA fog in Minkowski space? Hmm! "Damn it! ), "Degree of intensity and depth"(if the editor does not accept, compare "Strength of weight and size"), the species has a new feature "Quality", which you undertake to measure and subjectively divide into "Good" and "Bad"(as police officers in relation to the suspect), and this is a common plesiomorphic feature for all species, i.e. it appeared in the most ancient ancestor. Here they are the sources of good and evil!

This post was edited by Seneka - 28.01.2012 16: 09