A group of researchers in the Department of Environmental Evolutionary Biology at the University of Haifa and the Department of Science-Biology Teaching of the University in Oranim estimates that the toxin "amygdalin" found in almond nectar is actually an evolutionary development designed to give almonds an advantage over other plants.
It is already known from previous studies that the nectar of the almond tree contains the toxin "amygdalin" in concentrations of between 4-10 milligrams per liter. It is also known that the almond is the only plant in which this toxin is present in the flower nectar, and indeed the name of the almond in Latin is Amygdalus after this dangerous toxin. This toxin is fatal to small mammals and since it is found in high concentration in the seeds of bitter and unripe wild almonds, such almonds are dangerous even for human consumption.
A group of researchers, led by Prof. Ado Yitzhaki together with Prof. Gideon Naaman, Prof. Moshe Inbar and Dr. Natrigin Singarvelan investigated why the plant produces such a strong toxin, one of the products of which is the poison cyanide, precisely in the nectar. According to them, apparently the invention of the toxin amygdalin in the nectar contradicts the role of the nectar in the flower: to attract animals such as insects that come to the flower to obtain food and at the same time pollinate the flower and thus help the reproduction of the plant.
In the current study, the researchers allowed honeybees to choose between plates of nectar with different concentrations of the toxin and nectar without the toxin. For the first time, the researchers tested four different concentrations of amygdalin, which are similar to the natural concentration of the toxin in almond nectar: between 2.5-10 milligrams per liter. The second time the researchers tested concentrations much higher than the natural state: between 5-50 milligrams per liter. In both cases and in each of the concentrations, the bees tended to prefer nectar with amygdalin over "clean" nectar.
"It is difficult and sometimes even impossible to determine with certainty how evolution works, but it is likely that the production of amygdalin in the nectar gives almonds advantages in the reproductive process. Based on the observations in the study, we can speculate on the possible mechanisms by which the amygdalin provides this advantage," explains Prof. Itzhaki. For example, although amagdalin is toxic to mammals, it turns out that it is not toxic and even produces a stimulus that attracts insects such as the bee, so it is possible that the plant produces it to attract potential pollinators. Another possibility is that it is a substance developed by the almond as a filter - this substance will repel insects that are not "experts" in pollination, but will allow access to "experts" who on the one hand have succeeded in developing resistance to this poison and on the other hand will provide effective pollination services to the plant. These days, the team, in collaboration with Dr. Malka Halpern, Dr. Yoram Gershman and students Svetlana Friedman and Yana Gerstein, is investigating another possible mechanism - the toxin in the nectar prevents the colonization of bacteria that could harm the quality of the nectar, reducing its attractiveness to potential pollinators and thus harming the chances of pollination.
"Pollinating insects have always been a limited resource, so the plants had to develop ways to attract them to them and not to others, otherwise they would not be able to reproduce. This is not a theoretical assumption but a very practical one. Today, for reasons that are not yet completely clear, there is a great shortage of bees in the world. A worldwide crisis in the availability of pollinators is severely affecting agriculture and food supply for the human population. In the state of California there are huge almond groves that without bees will not bear fruit. "Due to the crisis in the availability of bees, the farmers there are forced to import, even from Australia, entire trucks with beehives during the almond blossom season so that they will pollinate the almonds," noted Prof. Itzhaki.
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It turns out that it is used for cancer patients, the treatment is against the opinion of the establishment
And in any case, it turns out that President Reagan, who suffered from three types of cancer since 1985, was treated with amygdalin, and also other senators today, American doctors work with this method in Mexico
to Michael Rothschild. You're probably right.
A byproduct of the poison is found in wild almonds
In the form of cyanide, the tree thus benefits twice:
Once in pollination and once in keeping animals away
that may eat the fruit (the question
It is of course what precedes what: the poison
in fruit or flower).
Nice article.
Just as a side note: it is incorrect to say almonds (just like there are no apples or oranges),
It's simply a mistake that took root because of Kipnis' children's song, a shake is a shake.
Yigal c.
I also think that there is an "overinterpretation" of the findings here.
This is probably what is called the co-evolution of Shakdia and Ambicia.
I think the real advantage - for both parties - is in specialization - in fact, loyalty to each other.
What is meant by?
Almonds have the advantage of satisfying the needs of species that prefer it so that they don't go to waste the dust they took from it when they go and suck nectar from other types of plants.
A specialist pollinator has the advantage of basing itself on the nectar of flowers that other species don't like because it increases the chance that when it lands on the flower it will actually have nectar inside.
The bees' preference for the smell of nectar with amygdalin is, in my opinion, a result of the general preference for this nectar and the amygdalin's contribution to its recognition. In my opinion, it does not derive from any nutritional advantage that amygdalin gives to bees.
The advantage that the amygdalin may give to both parties is in the creation of the specialization of which I spoke.
Some problematic things appear in the news:
1. The difference in the attraction of the bees to different amygdalin concentrations is not indicated, and if there is no difference (or it is not important) why did they do a follow-up experiment on this matter?
2. For cooperation between organisms, and especially one that requires evolutionary change, it is necessary that there be benefit to both parties. What benefit do the bees have to the whole thing?
3. Initially it is written that amygdalin is harmless to insects, so how can it be used to repel bad pollinating insects?
I didn't understand what it means that one of its products is cyanide?
"These days, the team, in collaboration with Dr. Malka Halpern, Dr. Yoram Gershman and students Svetlana Friedman and Yana Gerstein, is investigating another possible mechanism - the toxin in the nectar prevents the colonization of bacteria that could harm the quality of the nectar, reduce its attractiveness to potential pollinators, and thus harm the chances of pollination. "
It doesn't sound like a logical research direction to me. I may have a bitter mistake that will become clear due to the research, but as far as I understand, bacteria are animals with a very short life cycle compared to the life cycle of the almond tree. Such a short life time and the known ability of bacteria to react quickly to antibiotic substances poses to me a difficult question as to the direction of the research. Moreover, the abundance of bacteria is enormous in variety, so the likelihood of removing bacteria from the nectar seems somewhat low to me.
Greetings friends,
Ami Bachar