bird flies!
The last book of Michel de Pracontal (Kaluchua) is a good starting point for this issue, even if to defend the idea of animal culture caricature sometimes it prudent at this point some evolutionists. Take for example this incredible story of tits Swaythling (southern England): One morning in 1927 a tit a little more gifted than others discovered how to peck the milk of Swaythlinguiens (?), piercing the capsule bottles that filed the morning on their doorstep. This form of avian racket has spread throughout the city and in the nearby city and eventually won the country step by step, like an epidemic. She remained in service until 1949, when the system changed from closed bottles.
The only chance could explain such a spread of a new behavior, it was tempting to assume that the birds were passing the combines in one way or another. Pracontal sees this as the first discovery of a evolution "cultural" in the animal world, because "the tits have not changed for hundreds of thousands of years to become specialists in the opening of milk bottles. Furthermore, the process of decapping observed [which can vary depending on the type of encapsulation] does not fit the stereotyped sequence that characterizes the instinctive action. " The argument seems a bit light. First, to my knowledge no biologist takes birds or mammals for robots unable to adapt their behavior to novelty. Moreover, to assert that we are dealing with a phenomenon truly "cultural" in the tits, should prove that they are transmitted this practice from one to another. Now we can consider other explanations for this upsurge cheap milk.
Culture or prominence of a stimulus?
imagine such a tit scrounging, sated after so much feasting, leaving behind an open bottle. One second chickadee arrived to record untouched. "Yum! Milk in the bottle! "Motivated by this first experience, our chickadee is attempted to address all the full bottles she finds on her way and has a good chance of finding any single drill as their capsule. In this scenario the tits do not copy each other, they rediscover each the same practice by themselves, because the environment that promotes learning in the chain. In the 1980s, British researchers have experienced laboratory and showed that such a scenario is quite the road. We must therefore look elsewhere for convincing examples of true transmission cultural animals.
Ya good salted potatoes!
Could we have better luck with our cousins the apes? The island of Koshima in Japan hosts a colony of monkeys that researchers study and eat with potatoes since the 60s. One day, a female discovered by chance that the potatoes had better taste when they are immersed in sea water before eating. This practice has slowly diffused into the colony and continues until today. These are children who engage in such behavior in contact with their mother because adults are much most resistant to change (like yours!).
Pracontal sees this as a cultural obvious. But is there really transmitting know-how? Again, lots of researchers are skeptical and prefer a different track: is often near the sea at lunchtime, small monkeys are likely to rediscover their own interest to dip their potatoes in the sea environment promotes parental gradually adopting new behaviors. This learning by "social emulation" to explain Passage why this practice is spreading more slowly than if the animals directly imitating each other.
No accumulation of innovations without imitation ...
emulation, imitation ... one quibbles do you probably. Not really. The hypothesis of learning by social emulation assumes that each animal has to learn everything from scratch and can not learn from what others have already discovered. This scenario excludes any combination of innovative practices. If man had learned to carve the stones that way, that is to say if each individual had to rediscover the art itself in contact with its congeners, it would not go very far. In this configuration, because if someone found a way to improve this technique it would have had no way to pass this innovation to their peers. It's obviously much easier if the learning occurs through imitation of the details of the act of another. Imitation is the only way to access a cumulative evolution of behavior. The debate on the ability to imitate is not at all a battle over the sex of angels, is at the heart of what we could distinguish them from other animals.
Monkeys ape them?
Let us return to our sheep, or rather our rats. In 2006, a clever experiment finally seems to indicate that rats know imitate them: 
Paradoxically, this result has been more difficult to be detected in monkeys. In a famous article written in 1990, Italian researchers reported that capuchin monkeys do not know how to reproduce a sequence of actions they observe to get a reward. This statement ready yet controversial. On the one hand, the laboratory experiment on monkeys has its limitations:
- the animals are adults, so perhaps less likely to learn that young
- captivity is not probably not the best environment for learning.
- the demonstrator is a human and not a parent of a pet monkey supposed imitate.
In capuchins also the leader is always right!
Two dominant males were trained to operate a food dispenser, each by a different method (either by sliding or lifting a lever). We then replaced them with distributors within the clan. Within each clan other capuchins quickly learned to use the dispenser, but while most found the second method of operation, the vast majority just use the same method as the head (any similarity with humans ...)
customs and lifestyle of chimpanzees
With this great example of cultural conformity, reproduced successfully on chimpanzees, we would finally start long sought evidence that monkeys imitate them know. In reality, those who study animals in the field rather than laboratory have known for a long time. As recalled Pracontal, the comparison between the habits of chimpanzees in Tanzania and Guinea (mapping of the left source pdf) is telling: "A Bossou, Guinea when two adult females occur after been separated for some time, they are mutually genital touch. It's not sexual, it is a form of greeting, but it is specific to this site and did not practice at Mahale [Tanzania]. A Bossou to attract a female, a male pat on a branch with his heel, which produces a hit. At Mahale, the gesture is different, made with the sole (...) At Mahale, the power is removed with a leaf. At Taï, chimpanzees used his index and overwrites the parasite on his forearm and not his hand [as at Bossou]. These behaviors that we underestimated the importance is much more common as technological inventions that have taken center stage animal cultures. According to Nakamura and Nishida, these small gestures are the cement cultural group. Their subtle changes have no functional utility, but they define the identity of group. And demonstrate its unique history. "
This observation raises a question that does not Pracontal: why in these conditions cultural behavior of chimpanzees have they stayed so frustrated? Why are these monkeys also show an extraordinary intelligence have they failed to accumulate innovations, sophisticated in their rituals?
limits of imitation in chimpanzees
Nobody really clear answer to this question but it still seems that the capacity for imitation chimpanzees is both more limited and less used than humans. For example, in experience of 1993 it was shown captive chimpanzees how to retrieve food from outside their cage with a rake with the teeth facing up . Chimpanzees have tried to use the rake but not necessarily in the right direction, while young children are reached easily from the age of two years. Chimpanzees thus appear capable of observing a model, to link an object, movement and a result - this would explain the results obtained with the Capuchins, but they have more difficulty in imitating the exact details of the action when it is more difficult. In other words they focus on profit rather than on the process.
This limit is dramatically demonstrated in an experiment to fame: it shows a chimpanzee (or a young child) how to get out a reward of a box (either opaque or transparent) by all kinds of actions on the box, some useful and others not.
- When the box is opaque, one can not distinguish which actions are useful or not. Chimpanzees remake the complete sequence of actions to obtain reward, as well as humans. Proof once again that the chimpanzee known observational imitate simple movements.
- By cons, when the box is transparent and you see what actions are manifestly unnecessary, children remake anyway all the shares of the adult model, whereas chimpanzees skip unnecessary steps.
Upon s think nt understand how it works, the chimpanzee s s s ceases to imitate the process with accuracy and s research nt the solution their own s . He favors s nt naturally social learning through emulation. Children, however, attach more importance to the intentions and methods and spontaneously imitate their model. It seems extraordinary that rationality in this experiment either side of the animal rather than human, but in this case irrationality human seems at the heart of our ability to innovate, to earn the cultural changes and complicated rites. Copy "stupidly" Is it proper to man and the condition of his extraordinary creativity?
Sources:
Michel Pracontal "Kaluchua" (2010)
Cultural evolution , the excellent course at the University Sussex
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Darwin reloaded 3 : a first post on the habits and customs animal
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