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Animals take drugs. This is an undeniable fact which has been repeatedly confirmed by animal behaviour studies. Some years ago, Siegel gathered together many instances of such behaviour. At present, I am writing a book on the instances observed up to the present in an attempt to explain them in terms of what the biological literature refers to as the "PO factor" or "de-patterning factor". In brief, we may note that all living species including plant life are endowed with a set of primary functions necessary for survival nutrition, reproduction.
However, this is not sufficient. If a species is to preserve itself over time, it must be capable of evolving by modifying and adapting itself to its incessantly chaging environment. Apart from the rare cases of "living fossils", species which do not evolve will finally succumb. This is why each living species must also possesses that "evolutionary function" which is based, biologists believe, on the PO or de-patterning factor. The PO factor is probably reflected in the behavioural trait of drug-taking noted in animals and human beings.
In the last analysis, drug-taking may be considered a vital evolutionary function for the preservation of the species Samorini, "Animali che si drogano", work in progress. Siegel comes to the same conclusion, albeit by a different route. We already know that hundreds of natural species display this trait including, surprisingly, lower order species such as insects. Certain hawkmoth species - small nocturnal moths - have developed a long probosces to draw in the nectar of a jimsonweed species.
By doing so it aids the pollination of the flowers. Only after repeated observation of the behaviour of this species was it observed by some researchers that this hawkmoth appeared to be intoxicated by the nectar. This was in fact anything but obvious.
Firstly, observation took place by night when the plant's corolla opens. The main tasks of the botanists and entomologists who took the trouble to sit up all night beside the jimsonweeds were identifying the pollinating insects and capturing them while they were still inside the flower.
However, observation of the insects which had drawn in the nectar revealed that they "appear clumsy in landing on flowers and often missed their target and fell into the leaves or onto the ground. They were slow and awkward in picking themselves up again.
When they resumed flight, their movements were erratic as if they were dizzy. It is more than likely that the nectar of this species of jimsonweed contains the psychoactive alkaloids also to be found in those parts of the plant used by man for their hallucinogenic properties.
For hawkmoths, however, this is a very dangerous job indeed! If they lie besotted on the ground, even very briefly, or slowly fly away, they instantly become targets for predators. It appears that something of the kind also takes place with certain bees and American tropical orchid flowers.
Catasetum , Cynoches , Stanhopea and Gongora flowers are not sources of nutrition. They produce a liquid perfume. Bees of the Eulaema, Euplusia and Euglossa genera scratch the floriferous parts of the plants. This particular type of commerce between insects and flowers, whereby pollinated plants reward insects for their services with the drug as a part of the, or the entire, reward , is probably much more widespread than is recognized at present.
The behaviour exhibited by hawkmoths in the presence of jimsonweed led me to reconsider the behaviour of the common fly Musca domestica in the presence of fly-agaric.
The name of this mushroom "muscaria" is derived from the Latin for fly, "musca", because it is known that flies are attracted by the caps of fly-agaric and that they are "killed" as a result of contact.
In the past, indeed right up to our own century, fly-agaric caps have been placed on windowsills as insecticides. Often, the cap is or was crushed and mixed with sugar or milk to attract large quantities of flies.
In this manner, the flies would actually consume greater quantities of the intoxicant. The flies then dies, probably due to overdose. I have often noted apparently dead flies around the caps of the fly-agaric which I have prepared on various occasions preparation consists of stripping the cap of its gills to prevent rot and laying out the caps in a well-aired place for drying.
Unless one wishes to dry the caps with a warm air flow in an open oven, the natural length of time for drying the mushrooms can range from a few to many days according to the temperature and humidity of the surroundings. At times, I have counted dozens of flies which had "died" during the drying period. The number depended not so much on the number of caps laid out, or days necessary for complete drying, as on the number of flies in the vicinity. The "victims" of contact with the caps - lying on their backs with their legs up in the typical position of a dead fly - only appear to have died.
If you leave them alone and come back after an hour or so, or the next day, you will find that they have flown away! Normally, one would remove these "dead" flies, but perhaps others have taken the place of the first ones you saw, and have also been intoxicated by the caps. Seeing as we would find it hard to distinguish between individual flies, it is hardly surprising that we don't notice this turnover.
This is the reason for the folk belief that fly-agaric kills flies by poisoning them. However, a number of 19th century mycologists noticed that flies were not so much poisoned as drugged into a state of "lethargy" and it was recommended to those who used the mushroom against flies that they sweep up the immobilized flies and throw them into the fire see, for example, PAULET and CORDIER On careful observation, we see that the flies land on the cuticles of the fly-agaric cap and lick the surface.
After a while minutes some show signs of intoxication. They fly erratically or not at all; they become sluggish; a tremor appears in the legs or there is a trembling of the wings. Eventually, the flies will roll over onto their backs legs in the air, perfectly still. If you touch them with a pencil tip, some will exhibit no response while others will move their legs.
Under a magnifying glass, one may observe a persistaltic movement, which proves that these flies are not dead. Over a period ranging from 30 minutes to 50 hours, the flies wake up and soon move about in a normal manner. They then fly off as though nothing had happened at all. Some flies do not exhibit intoxication on coming into contact with the surface of fly-agaric. This may depend on the time of exposure to the intoxicant or rather, inebriant. There are probably various degrees of intoxication the signs of which range from markedly frenetic behaviour during flight, to complete catalexis.
The researchers wished to establish the degree of intoxication of this mushroom for the fly. However, their work tells us little about the relationship between the two species in a natural setting. They placed flies in Petri dishes together with the mushroom or a liquid extract of the same.
Many of the insects therefore died either due to overdose induced by the experimental conditions or - a point recognized by the researchers themselves -, specifically, due to the carbon dioxide produced by the mushroom itself, leading to asphyxia. These experiments established that the active principles of the mushroom acts upon the nervous system as opposed to the muscular system. It was also found that flies were intoxicated also by the spores of fly-agaric and by Amanita pantherina, a mushroom species similar to fly-agaric containing the same active principles and endowed with the same hallucinogenic properties for humans.
The most active portion of the mushroom is located immediately under the red cuticles of the cap. It is yellowish and is the region in which we find the highest concentrations of isoxazolic alkaloids ibotenic acid and muscimol.
It was once thought that muscarine was the fly intoxicant also for human beings. However, attempts at feeding insects with pure muscarine had no effect at all. It was shown, instead, that flies are intoxicated by the same alkaloids which intoxicate human beings. In Japan, mushrooms which attract flies have also been used for a long time as insecticides.
We should note that this mushroom is a carnivore. Ott is convinced that the neurotoxin is tricholomic acid i. It may therefore be the case that isoxazolic alkaloids are produced by mushrooms both as a means of protection against certain predators and as a trap for underground worms and that, 'by chance' these substances also attract and intoxicate flies which are clearly not a source of nutrition for the mushroom in question.
However, the problems remains: why should the maximum concentration of ibotenic acid in A. Furthermore, carnivorous behaviour has not been observed in these two amanitas. The grubs then move toward the gill area to feed. We may therefore imagine that isoxazolic alkaloids are insecticide to prevent the flies laying there.
If this is the case, we do not know why the maximum alkaloid concentration is in the cap just under the cuticle and not the stem, the preferred site for egg-laying. The muscimol concentration in the cap is 0. Furthermore, it is not clear that the grubs of these eggs adversely affect the sporigenic activity of these mushrooms the grubs would actually help spread the spores.
Lastly, the relation between fly-agaric and flies is one of attraction, not repulsion. This strange behaviour on the part of flies is not just a chance occurrence.
Nor is it by mere chance that flies are attracted by fly-agaric, or that intoxication rarely leads to death. Philosophically speaking, chance, or what we consider chance, is generally the measure of our ignorance.
Faced with chance occurrences, we tend to consider such circumstances in this manner and look no further. I would therefore like to advance a new hypothesis concerning the natural relationship between fly-agaric and flies also in view of the findings on hawkmoth inebriation and jimsonweed. Such behaviour patterns are not just recklessness on the part of flies attracted by fly-agaric accidental intoxication mysteriously brought about by a 'spanner' in the evolutionary 'works'. Flies deliberately seek the state of intoxication or rather, inebriation , as do hawkmoths with jimsonweed.
Flies, like the Siberian reindeer, take fly-agaric as a drug. In nature, the relationship between flies and their drug is non-obligatory. The flies exposed to this mushroom are not all "killed" i. The physical and mental effects of Cannabis smoking in humans are gradual. They range from the so called "high" a mental and partly physical state of excitation to a visionary or ecstatic state accompanied by sedation which can immobilize the consumer for hours on end.
The range of effects may depend on quantity, but other factors also come into play. Individual reactions to Cannabis vary and also depend on one's own personal relationship with the substance and how this has developed over time. If we consider flies, it may well be that, up to the present, our observations of the relationship with fly-agaric are just the tip of an iceberg and that other less evident aspects have been neglected.
Perhaps flies which are not "killed" by the mushroom are inebriated to a certain extent. Morgan has observed the effects of fly-agaric in a fruit fly Drosophila : "It made an attempt to fly off, and spiraled onto the table upon which the mushrooms lay.
Fly-agaric may be quite the opposite of an "artificial" paradise for any number of insects especially of the woodland undergrowth , and not just the common fly. The great ethnomycologist, R.
ISBN 13: 9788887999006
E avrei potuto aggiungere anche V. Nella foto potete vederne un esemplare in alto al centro, in basso a sinistra V. Nutrirsi e riprodursi. E molto spesso la nutrizione di uno comporta la morte di un altro
Animali che si drogano
Giorgio Samorini. An Italian ethnobotanist explores the remarkable propensity of wild animals to seek out and use psychoactive substances. From caffeine-dependent goats to nectar addicted ants, the animal kingdom offers amazing examples of wild animals and insects seeking out and consuming the psychoactive substances in their environments. Author Giorgio Samorini explores this little-known phenomenon and suggests that, far from being confined to humans, the desire to experience altered states of consciousness is a natural drive shared by all living beings and that animals engage in these behaviors deliberately.
Animali che si drogano
ISBN 13: 9788897109303