There are often opening sentences like, “only humans can x” or “only primates can x”. Why do people assume these sorts of statements are true without checking? Why does no one seem to complain? Either authors and readers don’t really care if the statements are true – they are just openers and not the important part of the piece; or they want the statements to be true and so are shy about looking at any evidence.
A recent paper (Anna Kis, Ludwig Huber, Anna Wilkinson. Social learning by imitation in a reptile (Pogona vitticeps). Animal Cognition, 2014) was reported in ScienceDaily with the opening line, “The ability to acquire new skills through the ‘true imitation’ of others’ behaviour is thought to be unique to humans and advanced primates, such as chimpanzees.” I knew this was not true and that other animals have this skill (a number of mammals besides primates and a number of birds). Looking at the abstract of the paper, I found a similar opening line. It was not so restrictive – “The ability to learn through imitation is thought to be the basis of cultural transmission and was long considered a distinctive characteristic of humans. There is now evidence that both mammals and birds are capable of imitation.” But even this is a bit restricted as octopuses also learn from one another. We should not be sure that some animal (an social insect for example) does not do x unless we have looked to see. And throw-away openings should be at least true.
But the paper has interesting news. Bearded dragons can learn from one another! Reptiles can be included too. We are more closely related to these reptiles than to birds. This finding strengthens the idea that social learning is an ancient skill in vertebrates, rather than separately evolved in various types of vertebrates. Although it is still reasonable to think that it evolved separately in invertebrates.
Here is the abstract:
The ability to learn through imitation is thought to be the basis of cultural transmission and was long considered a distinctive characteristic of humans. There is now evidence that both mammals and birds are capable of imitation. However, nothing is known about these abilities in the third amniotic class—reptiles. Here, we use a bidirectional control procedure to show that a reptile species, the bearded dragon (Pogona vitticeps), is capable of social learning that cannot be explained by simple mechanisms such as local enhancement or goal emulation. Subjects in the experimental group opened a trap door to the side that had been demonstrated, while subjects in the ghost control group, who observed the door move without the intervention of a conspecific, were unsuccessful. This, together with differences in behaviour between experimental and control groups, provides compelling evidence that reptiles possess cognitive abilities that are comparable to those observed in mammals and birds and suggests that learning by imitation is likely to be based on ancient mechanisms.