The research focused on examining 51 different species of nematodes (millimeter-long worms) that diverged from an ancestor at different stages of evolution. The researchers examined the egg-laying organ - holwa - of the various nematodes, and tried to assess how it was formed during the formation of these nematode species from the ancestor
Scientists at the Technion discovered that evolution is not random
The theory of evolution which began to take shape during the 19th century proposed that life on Earth was created and developed to the present day by a gradual process of the formation of species from other species and the variation of certain traits within that species.
One of the main weaknesses of evolution was the lack of a mechanism that would explain how it works. In the mid-19th century after extensive research and careful examination of hundreds of examples, Charles Darwin proposed natural selection as the mechanism through which evolution occurs.
The basic premise of natural selection is that organisms undergo changes in each generation. These changes are completely random, and are actually the engine of evolution. But if there is no directionality, that 'engine' just rattles in place and does not drive evolution in any direction. Darwin proposed that directionality is determined by the mechanism of natural selection.
Darwin's breakthrough was his understanding that changes that occur randomly are measured in the way they adapt the organism to the environment. As a creature is more adapted to its environment, it is able to give birth to a greater number of offspring, each of which carries the change and therefore it can also give birth to a greater number of offspring. In this way, after several generations, the number of individuals in a certain species that carry the change can be much higher than the number of individuals that do not carry the change. In this case the change actually takes hold, and is preserved for future generations and this is the way in which the mechanism of natural selection turns randomness into directionality. Several important discoveries in the 20th century formed the molecular basis for the mechanism of natural selection by characterizing the changes as mutations that occur in DNA.
Towards the end of the 20th century, claims began to emerge that there are other mechanisms different from natural selection that can explain the variation of creatures and traits. The researchers who made the same claims did not question the existence of evolution through natural selection, but they suggested that certain mutations are not identified and are not determined by the mechanism of natural selection because they do not contribute to the survival of the organism.
An example of such a feature could be the human appendix, which has not yet been found conclusive evidence of its activity in the human body. Mutations that affect the function of the appendix will not affect human survival and therefore will not be recognized or eliminated by the natural selection mechanism. This will cause a random evolution of the appendix by the accumulation of random mutations in this organ.
In order to test the idea of random evolution, an international collaboration was created between researchers from the Technion, the University of Paris, New York University and the Max Planck Institute for Developmental Biology in Germany. The lead author of the final article in the journal Current Biology is Dr. Karin Kiontka. At the Technion itself, Doctor Irina Kolutoyev and Professor Benjamin Podbilevich conducted some of the experiments described in the article.
The research focused on examining 51 different species of nematodes (millimeter-long worms) that diverged from an ancestor at different stages of evolution. The researchers examined the egg-laying organ - holwa - of the various nematodes, and tried to assess how it was formed during the formation of these nematode species from the ancestor. The researchers expected to find that if the evolution of the organ was indeed random, no developmental trends would be formed and the development of the organ would be random among different species without defined directions of development.
For each of the nematode species, the researchers estimated where that worm was placed on the evolutionary scale. The assessment was carried out by analyzing similar DNA sequences in different worms, and based on the examination of the morphology of the worm. After that, more than 40 different features were tested in the development process of the laying organ of the worms. The researchers reviewed the cell division patterns, the variety of cells that commit suicide in the process and other features related to the development of the gonad. The different hyacinths were examined with the scanning electron microscope and the light microscope, as well as by staining for different proteins and cells in the area.
Although the researchers expected to find no improvement in the mechanism of hyogen formation, the conclusion was unequivocal. Almost all the evolutionary changes undergone by ugines were in one direction only. The number of cell divisions required for the development of gynae, for example, decreased as species that diverged later were looked at, instead of increasing and decreasing randomly. In addition, the researchers noticed that the number of rings that make up a hydrangea decreases during evolution. In summary, the progress of evolution in nematodes was accompanied by the selection of specific and directional changes from the large pool of random changes.
From all of the above, the team of researchers came to the conclusion that evolution does not proceed through random mechanisms. And the grammarians will add - at least as far as the vaginas of the nematodes are concerned.
Thanks to Dr. Amir Sapir from the Faculty of Biology at the Technion, who agreed to be interviewed for the purpose of preparing the article and to Professor Podbilevich who went over the first drafts, corrected and advised how to improve.
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In any case, although it seems logical to me that psychology also affects our physiology, and that a calm and happy person will heal faster than a tense and depressed person, only research will convince me on this issue.
All well and good but how was the first nematode vagina formed? Was there a nematode without a vagina? With another breeding method? Or maybe it was another animal. Who explains?
Hahahahaha LOL!!
You don't really need TRIZ for that
Anyone who knows evolution or understands mathematics comes to this conclusion easily.
The thing is that science is never based only on logical arguments and it strives to base its conclusions on experiment.
In addition, since we live in a demon-possessed world, he also needs to find reasons that the opponents of evolution understand.
The fact that evolution has a preferred direction is no surprise to those familiar with TRIZ, a theory for creative problem solving. (TRIZ acronym in Russian)
One of the fields in TRIZ is the evolution of technological systems and it is a well-known fact that parallel systems undergo a parallel evolution. This is due to the fact that the main criterion for the improvement of any system is the same: striving for the system to approach ideality. If possible, systems become simpler in certain ways (for example, the number of cell divisions in a nematode) and more complex in ways related to efficiency (an enzyme that performs a certain action for two needs splits into two similar enzymes, each optimal for a different process)
What's new:
What you say is exactly the intent of the article and it is not clear why you are arguing.
The article does not claim that the mutations are not random, but that the selection that chooses the most suitable ones selects them non-randomly
Interesting but problematic...
It is not always easy to see the factor that creates selective pressure.
1. The conclusion from these findings, as presented here, is based on the assumption that the number of cells is not affected by selective mechanisms. This assumption is not necessarily correct. Fewer cells may give the worm an energetic advantage, and perhaps this is the reason why there is no increase in their number. It is very difficult to prove ideas of this kind.
2. It is possible that the trait regarding the number of cells is in the grip of another trait that is under selective pressure and therefore it is preserved.
That's why I don't see the contradiction in terms of randomness in the evolution of species.
For age
You can clearly explain who is behind the intelligence of nature.
Or maybe you mean the intelligence of the raindrops or the volcanoes or maybe the asteroids, or how great is your wisdom, no one in the city could know as a fool would not understand.
Father, I don't know where you get your strange interpretations of religious coercion? How did you come up with this?
Apparently there are people who only see what they want to see there.
and are more engaged in the war between religion and science.
All of nature is full of intelligences that force life to continue in certain directions.
There is no planning here.
To Ami Bachner:
Why did you raise the molecular clock question?
There is nothing in the article that relies on it.
Even if you have reason to dispute the dates on which the various changes occurred, you will have no justification to question the order in which they occurred and that is all that is at play here.
For a point of debate:
Avi Blizovsky responded that Gil once again pushed his religious belief into scientific discussion and tried to present his belief as scientific truth.
Instead of commenting on it, you comment on the fact that my father resented it.
Besides, when you say that the randomness is incomprehensible - please qualify the things and speak only for yourself.
For those who have studied the subject, it is understandable.
With this reservation, I will also accept your words that when the matter is understood (by you), it will cause (you) to reevaluate things.
Much ado about nothing…….
To my father Blizovsky
Scientific rigor is agreed upon by most of those who deal with it. But rigor in someone's belief that their words allude to a creator of the world is puzzling to me. After all, you yourself are fighting against the religious coercion that is required for such careless grammars.
Science is not a religion and there is no need to bother with the intentions and beliefs of people with this or that point of view.
For the article itself. The main argument is based on examining randomness and its inverse. With all the scientific developments, the understanding of the subject ie "randomness" is still very, very far from complete.
In my opinion, when things are well understood, it will cause many things to be re-evaluated.
Gil, it follows from your words that if someone planned us, he is probably not intelligent.
I join in the congratulations of Ami Bachar
A year of discoveries and new beginnings!
Ami,
Species are differentiated by their ability to mate and produce fertile offspring with each other. In the article, different species of nematodes were taken, and not variations or strains within the species.
Regarding the reliability of the 'molecular clock' through which the estimated time when the species diverged from each other is extended, it is not in doubt in my opinion. Such methods have been used for a long time, and in general, when you use several genes for dating, you get evidence that supports each other
Regarding the vagina and the fact that it is 'super-functional', I agree with you that this is how it appears at first glance. At the same time, this particular research was started precisely because in the bugs of different nematodes one could find diverse and seemingly random variations. The nematode's vagina was actually one of the potential evidences of random evolution. The researchers approached the study with the assumption that this was the case, and discovered 'to their surprise' that most of the changes in its vagina are not random, but rather simplify the process of its creation as the worm becomes more modern.
I agree that in hindsight it would have been better to conduct the research on a less useful organ, but I'm not sure how easy it is to find in a worm's body that contains only 959 cell nuclei, each with its own vital function.
In any case, a large part of the credit for the article should go to Doctor Amir Sapir and Professor Benny Podbilevich, who went through the article word-by-word until it was clear and precise enough.
Thank you, and Happy New Year to you and all of us,
Roy.
Gil, are you trying to imply that the religious coercion does not come from people who believe in something and are unable to understand that they are wrong, but from a higher source? Is this what the forced rational nature meant?
How can humans impose a human trait on nature?
Randomness is a nice word, but randomness only makes sure that the genetic material replicates in small shifts in all directions.
Too sharp a change will not survive.
So in the end the only operation of randomness in nature
is the ability of the genetic material to change.
In practice, what causes the genetic material to change in different directions
is the forced rational nature.
I really liked the first part which explains well and clearly the mechanism of evolution.
The sentence "For each of the nematode species, the researchers estimated where that worm is placed on the evolutionary scale" is problematic. If we are talking about different species of nematodes, then they may have different origins. If it is the same species, then the correction must be added that explains that the assessment is an assessment of the genetic difference or similarity (and the grammarians will add - in a certain gene) and it refers only to the group of the species and the tested varieties. In other words: it is not a kind of evolutionary hierarchy between the different varieties of the same species, but a mere variation or difference of the same species between its different varieties. Such studies have recently been done mainly in microorganisms and the accepted name for them is "biogeography".
Another question arises regarding the reliability of the "molecular clock" through which it is supposedly possible to date the formation times of the strain/species in relation to other species. Like the concept of evolution, also in the case of evolutionary clocks it is a numerical hypothesis that is difficult to impossible to prove in real time (perhaps something similar can be shown in short generation animals such as bacteria - but certainly not in vertebrates).
The research is interesting and the article is enlightening - to the best of my recollection, this is not the first time I have read it and reacted critically. The choice of this specific organ as the object of the study is also problematic since it is a super functional organ (which is why these results are really requested). I wonder what would have happened if they had chosen another organ as the example of the human appendix or in its analogy in nematodes (an organ that on the face of it has no meaning or contribution to producing fertile and competitive offspring).
With the blessing of a good civil year to everyone and Roy in particular. I hope that in 2008 you will continue to create such great articles for us in the best of your tradition.
Ami Bachar