I am in complete agreement with Alphagruis on the preponderance of training and culture in several fields, particularly in visceral attraction for sauerkraut and fresh butter... As for knowing what kind of motivations pushes the apes to consume medicinal plants, it would be essential to ask them to know the truth.
I observed several times that animals can find medicinal plants without any training: for example cats separated very early without having had time to make the least ramble in the nearby fields in company of their mother, can recognize the specific grass (catnip) and consume it in case they have intestinal problems. It’s the same for other animals.
In addition, I noticed that humans are language gifted, which provides the advantage they can be asked the reasons of their behaviors. They systematically describe modifications of olfactive attractions exerted by the medicinal plants according to their health condition. It stands true for example for cassia fistula, which takes a bitter, nauseating smell in case of diarrhea tendency and change to Belgian chocolate in the event of constipation.
This leads me to think that animals, whose sense of smell is by far more efficient than that of the remains of apes we are, can recognize among the natural pharmacopeias the specific plants useful for them, and that the first detections made on the ground are then memorized and transmitted by imitation, i.e. they enter the “culture” of the group. This point of view is compatible with the opinion of the researchers as it appears from both of these sentences: "strongly suggests a common criteria of medicinal plant selection" and "suggest the existence of an underlying mechanism for the recognition and use of plants and soils with common medicinal or functional properties".
The innate and acquired cannot be dissociated, hence this apparent oscillation from one to the other in explanations of behaviors. It seems to me equally stupid to put everything on the account of the acquired as to put the whole lot on the account of the innate. Personally, I never thought nor said (contrary to what Alphagruis insinuates) that the existence of innate alliesthesic mechanisms excludes in any way the utility of training. Quite on the contrary, a training is imperatively necessary so that conditionings against nature remaining from the culinary context get erased and leave the field free to the innate reflexes. It’s this rehabilitation of the instinct that constitutes the main part of the instinctive nutrition practice such as I defined it.
For the question expressed
here by Alphagruis: “Why would it be necessary to transmit that by culture between the animals if each animal can find these plants all alone with its supposedly alimentary "instinct" or else?” the answer is simple: it is advantageous from the evolution viewpoint that the instinctive mechanisms (in particular alliesthesic mechanisms) are integrated in a transmissible group’s behavior by imitation. It shortcuts the necessity to wait for the animal in need of a particular plant to passes by chance in the vicinity to be able to profit from it: the “culture” of the group is given the job to put him in situation. He can then consume it insofar as his olfactory and gustatory mechanisms indicate the plant usefulness to him. The SWD fed zoologists who observed the phenomenon certainly found a bitter taste to the sheets the chimps chewed, but the latter, practitioners of instinctive nutrition since early childhood, would obviously have found a very different flavor to it.
Yet, what is advised by the “instincto” model? To place at disposal, on the basis of our knowledge of the human food range (thus of the culture), all that is prone to be consumed, so that the instinct (thus nature) can decide under the best possible conditions which are the most suitable stuff to ingest at the moment. It has never been question of letting the sense of smell lead the consumers towards an useful food located miles away, but rather of benefiting from the little smell ability we still have left to recognize the most appropriate food in a given choice. Could Alphagruis have understood my position, this time?
gcb