Tasmanian devils are dying from an epidemic of contagious cancerous tumors. The species undergoes a rapid evolution that leads to the advancement of sexual maturity and allows females to conceive at a young age, before they die from the plague
A pocket predator lives in South Australia and Tasmania. His "creaking" screams, his strange shape and his bad temperament gave him his popular name: 'The Tasmanian Devil'. After the large predator - the pocket wolf - was exterminated, the Tasmanian devil remained the large predator (except for the dingo, which is a "feral" of domestic dogs).
In recent years there has been concern about the continued existence of the special predator. Since 1996, a plague has been attacking the devils that has received the name "devil facial tumor". Contagious cancerous tumors attack the demons and kill them. The tumors develop in the area of the face and mouth, causing deformities that prevent the animals from eating, and at the end of a period of hunger and suffering the animal dies. Those who are attacked by the disease, most of all, die at the age of two to three.
It is not clear what the cause of cancer is, but many researchers blame the human influence, since it turns out that the farther the demon populations are from human populations, the less the plague appears. In order to prevent the extinction of the demons, groups were moved to isolated islands in the hope that within some time it would be possible to identify the cause of the disease, treat, cure and prevent its further spread.
The risk to the Tasmanian devil populations led the Australian and Tasmanian authorities - the Australian Research Council, the Australian National University and the Tasmanian government - to study the life cycle of the Tasmanian devil, as part of the Save the Tasmanian Devil program.
Last July, zoologist Menna Jones published the results of her research in the respected scientific journal, Proceedings of the National Academy of Sciences. Jones writes and describes the conclusions she reached and the findings describing "evolutionary becoming before our eyes".
A healthy Tasmanian devil lives about six years. At the age of two-three (weighing about 10-15 kg) he reaches sexual maturity and reproduces. However, as a result of the disease, even females that give birth at the age of two will not have enough time to raise the child, and thus the danger of the plague increases and threatens to destroy the demons.
Here "evolution comes and works" in favor of the existence of the biological species. Natural selection tends to favor individuals that mature (sexually) faster. The young devils mature sexually at a greater speed and begin to reproduce already at the end of the first year of their lives (when their body weight does not exceed 6 kg). In this way, the rapid maturation "catch up" with the rate of development of the epidemic and thus the species is given an opportunity to continue to exist.
Jones notes that "to her knowledge, this is the first case in which an infectious disease causes sexual maturity to be brought forward in mammals." It is estimated that without the evolutionary "exercise" the Tasmanian devils would have disappeared within 25 years. The surprising evolutionary development gives researchers a window of time to develop a means to stop the epidemic and allow the Tasmanian devil populations to continue howling, screeching and fighting among themselves.
37 תגובות
point:
If you meant to tie it to the word Devil then well done.
If not - it still turned out funny. 🙂
Demons used to be scary.
Obviously there was an evolution (devolution)
Roy,
I would be surprised if in the future they don't see an evolutionary development as a response to disease in Taz and his friends. What bothered me is that, contrary to what can be understood from the original article, it can be understood from the knowledge that scientists have already seen evolutionary development and natural selection among the demons, and not that this is just one possible explanation. At the moment it is possible to explain the change in a similar way to a phenotypic change in height following a poor or rich diet.
Beelzebub,
I appreciate your caution, which is well-placed. The article does describe a situation that was discovered for the first time in nature. This situation can be defined as an evolutionary development, and I would not be surprised if researchers who analyze it in a few years come to a similar conclusion.
Avi,
Thanks for restoring some of the messages (even if it caused some unnecessary duplication).
My father and Michael,
I have no doubt that the theory of evolution is correct, at least according to all the evidence they have found so far, and that you can see examples of it even today. My argument is that despite the use of words that may be interpreted as evolution, and even though it is clear that the researcher believes that eventually as a result of natural selection the trait she describes - or other traits she mentions such as resistance to disease, or less violence - will take root in the population as a result of selection, the article itself does not describe a change as a result of natural selection.
In the discussion of the article, Jones writes that the phenotypic change in reproductive age is due to a change in food availability (as I have already mentioned) and also states what is new in the article - the first time such a change has been seen in a natural mammal and also, since she believes that the disease creates strong selection pressure, an opportunity to investigate and see if it really occurs Here is natural selection and what evolutionary change will happen in the population (all of this as part of the plans for the future and not part of the current research that only reported a visible change in the field)
To Baal Zevov, in your responses that contain words that the system recognizes as words common in spam messages, write only Hebrew and in the worst case, translate the words into Hebrew so that they pass the filter.
It's hard to find your messages among hundreds of spam messages after the fact and I must have missed and deleted some.
In any case, there is no need to be caught in a police investigation regarding the meaning of words, natural selection is part of evolution, evolution is the factor described by the researcher even if in the press release it appears in one of its biases. Everything else is just the twisting of evolution deniers.
Beelzebub:
I can't refer to what was not published but I mean what was published is not wrong. It does not depend on the rest of the article at all and is simply a question of reading comprehension.
I also don't believe that the system censors parts of comments and in any case you could add in the last comment what was missed in the previous one and you know what? You can still do so in the next comment!
Belize There are many processes processes that are evolutionary in nature even though they are not biological. And you should stop getting caught up in this or that term or what this or that researcher thinks, try to understand what it is about.
By the way, even those who read the report in the third link can see that it says:
The team believes some females are reaching sexual maturity faster and reproducing sooner because the heavy toll of the disease has freed up food and created less competition for mates
Only then does the researcher describe to the magazine how she thinks natural selection can also have an effect.
By the way, even those who read the report in National Geographic can see that it says:
The team believes some females are reaching sexual maturity faster and reproducing sooner because the heavy toll of the disease has freed up food and created less competition for mates
Only then does the researcher describe to the magazine how she thinks natural selection can also have an effect.
Despite what she says (to the magazine, not in the research), in order to check whether her discovery of the change in behavior is not only due to changes in food availability (for example) it is necessary, at the very least, to perform an experiment similar to the one described in my first response to this news
Michael,
Unfortunately, for an unknown reason, the system does not allow me to publish the rest of my response, so you only responded to the part that I was able to publish. In any case, as is clear (despite your misinterpretation) to everyone who read the article, and in all the reports about it - the researcher believes that the change is due to evolution and hopes that further research will reveal that she is right, but the published study only refers to the Zionists at reproductive age and states that this is probably due to the availability of food.
Any reference to evolution there is a hypothesis and hope of the researcher and ideas for future research.
Since we are not talking about evolution, but about the appearance of new behavior, the meaning of the word evolve is not as you chose to interpret it, but as is accepted in English-speaking countries. In any case, there are enough other (and much better) studies that demonstrate evolution - some have been published on this site and some have not yet (Lansky, for example)
Michael:
(Continue the comment in the hope that this time the comment system will publish and not return an error message)
In the third article, as you wrote, Jones presents cases that may develop as a result of natural selection. These are the same things I wrote at the beginning "... the evolutionary adaptations can be resistance to disease, non-violent mating or even early puberty". An existing situation is not described, but possible adaptations under the (justified) assumption that a fatal disease leads to strong selection. At the opening of the third link (National Geographic) it even says that:
The team believes some females are reaching sexual maturity faster and reproducing sooner because the heavy toll of the disease has freed up food and created less competition for mates
Beelzebub:
You take phrases out of context and misinterpret them.
Here we are talking about evolution and there is absolutely no difference between the "different" meanings of evolution.
The theory of evolution talks about one of the mechanisms that lead to evolution, but it does not redefine the concept.
The first link I used is the one you sent first.
He talks about evolution and did not invent any new meaning for the word.
He certainly does not give any evidence to your counter claim. This reminds me a bit of the ultra-Orthodox's defense of the Bible's claim about raising the migration of the rabbit by claiming that the rabbit in the Bible is not what we call a rabbit today.
Actually, on further thought, because of the distance of time, the above claim of the believers is a little less ridiculous.
The quote you bring from PNAS also does not say what you are trying to attribute to it. Actually just the opposite. There is an assumption here that this is evolution and a question only about its possible reactions in the long term and its ability to save the species in question.
The word evolve or evolving in English also has separate meanings from evolution. It is possible to evolve a new behavior, for example, without Darwin's evolution being involved. Indeed, in the first link you mentioned, the use of the word evolving is not related to evolution, especially when you look at the quote from the abstract of the article (below).
As I already wrote, even the researcher who conducted the study does not claim that this is evolution, but only that it may raise questions about evolution. All she says is that this is the first time that an infectious disease has been seen to advance the reproductive age. From PNAS:
To our knowledge, this is the first known case of infectious disease leading to increased early reproduction in a mammal. The persistence of both this disease and the associated life-history changes pose questions about longer-term evolutionary responses and conservation prospects for this iconic species
What's new:
come on!
The changes in animals often happen as a result of an evolutionary shock created due to the change of the environment.
The disease, in this case, is part of the environment.
You tell us: restore the environment to its original state and everything will return to its original state.
This is a meaningless statement.
Beyond the fact that it is not certain that Hyatt is right - if everything goes back to the way it was - this will also be evidence of evolution.
Evolution is a collection of change steps that increase the chances of genes to survive in the environment in which they are kept and it is mainly expressed when there are changes in the environment. When changes are in opposing directions alternately - the evolutionary pressure also alternates alternately.
You have been ignoring all my words for a long time - probably because they are not convenient for you.
There are those here who give greater importance to the term itself than to what the term comes to describe ==> unscientific thinking.
Avi Blizovsky,
The average life expectancy of the sick group is about 3 years due to the disease
This is not the natural life of the group. The minority group that matures faster has not undergone any change, it has always existed and survived, but this is not the natural situation.
They live in a state of deadly disease.
It's like if you killed every late-maturing symptom demon and then only the fast-maturing ones would be left.
The test of evolution will be after the disease in the group disappears and then we will see if
The rapid sexual maturity trait will survive.
In my opinion you will not survive because in the natural state when there is no disease, then the rapid sexual maturation has no advantage.
What's new:
Don't you feel the inner contradiction in your words?
"A temporary change...that will return to the previous state if the disease disappears"
And what if you don't disappear?
And what if you disappear only after the genes for late development have already been completely wiped out?
The difference between the wolf and the dog would also have disappeared if man had not survived long enough and completed domestication, and the differences between the polar bears and the other bears would not have developed if the ice had disappeared early enough.
I don't think you are taking seriously what I have already written to you.
And how there is a real change from generation to generation - an increase from a negligible prevalence of Tasmanian devils breeding at a young age to a prevalence of 100% or close to it. The most correct definition of evolution that I have heard is a change in the frequency of a gene in a population over generations.
That's exactly what happened.
Avi Blizovsky,
There is no real change from generation to generation
In total, the minority group became the dominant group as a result of the disease
In the future there could be one of the following scenarios:
1. Or the entire group infected with the disease will become extinct and this is because the age of the disease has decreased
And even if the age of the disease does not decrease, it is likely that they will disappear.
2. If the disease disappears, there are 2 scenarios:
A. That the entire group will reach early sexual maturity seems unlikely
Because the reason for early sexual maturity will disappear (the minority group before the disease that reached early maturity was not just a minority group, it probably had its drawbacks).
B. That the minority/majority group will return to the same as before the disease and this seems more likely because this is the natural state throughout the life of the symptomatic breast.
In conclusion, it seems that there is no evolutionary process here, but a temporary change due to the disease
which will return to the previous state if the disease disappears.
In the end, any trait that is preserved through generations
Indicates an evolutionary change, sometimes it is a feature
Looks like the length of the claws, the color of the skin, the hair
Or the eyes and sometimes it's another feature - like age
sexual maturation.
Beelzebub:
In the first link you sent - at the very beginning it says:
The new paper by Menna Jones and colleagues claims that the population is evolving towards a radical life history solution to the problem
The word Evolving is derived from Evolution and vice versa.
This is the summary of the article at this link.
The second article requires an appointment and I did not enter it.
On Tuesday it says:
The natural selection could be for "disease resistance, early breeding, or behaviors that keep the devils out of trouble," Jones said.
Again - this is natural selection, which is part of evolution.
Of course, the selection is between those with the various traits that are inherited because otherwise no change would occur except for the reduction of the population.
That is, evolution again.
On the second page of the same article, they even go further and say that not only is this evolution, but that it may be a feature that evolution will eventually determine:
it could become an "evolutionarily fixed" trait for the species, scientists say
In short - it turns out that I did the right thing.
I relied on the translation and it was reliable.
I didn't rely on the links you didn't send - I contented myself with asking you to provide them and provided I received proof that the translation is reliable.
why new Your settings exactly correspond to what was described in the article - a change from generation to generation so that the next generation reproduces earlier. In fact, what happened is that those who are not able to reproduce before they get cancer simply do not produce offspring, therefore all the offspring in future generations belong to those who gave birth early.
What's new:
It seems to me that it is.
In any case - if the argument is only about words then it can be waived.
Michael,
Definition of evolution in the Hebrew Wikipedia:
Evolution (Latin: Evolutio[1]) is the process of genetic change in a population of organisms[2] over the generations.
The definition of evolution in Wikipedia in English:
In biology, evolution is the process of change in the inherited traits of a population of organisms from one generation to the next.
It seems to me that these definitions do not correspond to the concept of evolution in the article.
Michael,
Contrary to what is written in the news in science, even the researcher who investigated the study does not say that it is evolution but only that it may raise questions about evolution. All she says is that this is the first time we see that an infectious disease causes the reproductive age to advance (http://www.pnas.org/content/105/29/10023.abstract)
Additional reports:
http://johnhawks.net/weblog/reviews/life_history/tasmanian-devils-early-breeding-2008.html
http://sciencenow.sciencemag.org/cgi/content/long/2008/714/1
http://news.nationalgeographic.com/news/2008/07/080715-devil-mating.html
It's a shame you responded without searching the data or reading the article
What's new:
These puns are pointless.
Evolution chooses (through natural selection) the most suitable among the various combinations of genes and makes no effort to answer whatever your definition of the word evolution is.
If the conditions return to what they were and if the earlier versions of the genome still survive and if they really become superior, the situation may return to the way it was before.
If the disease disappears in some areas and remains in others, it is possible that the species will develop over the years into two completely separate species.
If the disease remains, at least until the last of the late-maturing ones lags behind, then we will only remain with the early-maturing ones - at least until - if it happens - a reverse mutation that will or will not return the situation to its original state.
All of these scripts are evolution whether you choose to call them that or not.
Evolution works slowly so its products are usually not revolutionary.
In every route that leads between control of species A and control of species B there are stages in which both species exist - these are stages in evolution and they will remain so even if control of species B never comes.
why new Regarding the blacks in the USA. If they reproduce because of adaptation to the environment then since this is a phenomenon that establishes the principles of evolution it will be called evolution.
Perhaps it is possible to separate between weak evolution where there is no change of sex, and between strong evolution where there is change of sex.
Then a strong evolution is usually an accumulation of many weak evolutions.
Roy,
Blacks in the US are a minority group.
Let's assume that the improvement of socioeconomic conditions will cause them to have a high natural reproduction
And they will be the majority group in the US.
Is this evolution?
Roy,
The change was caused by the disease.
There is a possibility that the disease will break out at an earlier age due to early puberty, and then they will all become extinct or,
If the disease disappears (by itself or through treatment), it is likely that the group that is late to reach sexual maturity will become dominant again.
Will in this case it be a repeated evolution?
why new
First of all, we must understand that any change in the animal's features is real.
Add to that the fact that each offspring is not identical to its parents.
It is not evolution that creates the mutations but the mechanism of genetic replication.
The environment "reinforces" the adapted.
This is evolution.
What's new,
Evolution by definition examines populations of animals. Therefore, if the ratio in the population suddenly changed to 90% demons maturing early versus 10% demons maturing late, this is definitely evolution since a large part of the population now expresses a trait that previously only existed in a small number of demons.
Baal Zevov said that evolution always relies on genetics and changes in genes or the genome, but this assumption is being undermined today due to evidence proving that evolution can also occur in epigenetics (protein mechanisms that control gene expression).
"Natural selection tends to favor the individuals that mature (sexually) faster. The young devils mature sexually more quickly and begin to reproduce already at the end of their first year of life."
If I understood correctly then there was always a minority group that sexually matured faster.
In this case, because of the disease, the minority group has an advantage since the females will be able to raise their offspring before the disease breaks out.
And if the disease disappears on its own or through treatment, it is likely that the group that is late to reach sexual maturity will become dominant again.
Is in this case natural selection = evolution
Or that evolution is a process that includes real change (genetic, shape, size) and will last longer.
Beelzebub:
The researcher who studied the subject says it's evolution and you without data say it's not.
Well done!
According to the story told here, this means evolution.
You are talking about "most reports on the study".
I wonder where you got them from.
Can you share them with us?
And what about the original research? Do you think the researcher who wrote it did not read it?
What's new,
Caption fixed, thanks.
Error in the caption below the picture
Not an extinct Tasmanian wolf, but a Tasmanian devil that still exists
It has nothing to do with evolution, I agree with Beelzebub.
The find is (almost certainly) not an example of evolution.
In most reports on the study (and also in the study itself) it is said that the devils started mating at an early age - "puberty" - since with the death of the adults, food resources were freed up and the competition for potential mates decreased. That is, the change in sexual behavior is not due to evolutionary adaptation.
The behavioral change that causes demons to mate at a young age may postpone the end for them and thus extend the time in which an adaptation against the disease may develop. The evolutionary adaptations could be resistance to disease, non-violent mating or even earlier puberty, but currently no such adaptation has evolved.
The article claims that since the behavioral change in mating age allows devils to have offspring and raise them before the parents die of cancer, it is possible that selection pressure will eventually determine this trait (mating at a young age) in the population. However, the researchers did not show that there is a genetic component to the change in mating age. One way to test the source of the change is, perhaps, by increasing the availability of food and mates and reducing the competition for young devils in captivity. If this causes a change in their mating age, the source of the change is behavioral/environmental.