If you place a rat in a maze with no food, the rat will simply run around the
maze, familiarizing itself with the surroundings. If you then return the rat to
the same maze the next day and add food, the rat will find the food much more
quickly then will a rat placed in the maze with food for the first time. This
is an example of latent learning. The rat has familiarized himself with a
stimulus in the absence of any association with a positive or negative stimulus.
Imitation
Many animals learn by imitation of conspecifics (same species animals).
Macaques learn to wash sandy food by watching other members of the same species
do the same. Another example of learning by imitation is the mobbing behavior
of birds. European blackbirds mob predatory birds, such as owls, to chase away
or perhaps kill the potential dangerous enemies. In an experiment to determine
if this was a behavior learned by imitation, a naïve and experienced bird were
each placed in view of each other, but separated by a glass partition. The
experienced bird's enclosure contained an owl, and the naïve bird's enclosure
contained another, harmless bird. Most of the enclosure was separated by an
opaque partition, so that the naïve blackbird could not see the owl. When the
experienced blackbird mobbed the owl, the naïve bird similarly mobbed the
harmless bird. It appears that the naïve bird was learning its behavior from
its conspecific; it did not know not to mob a harmless bird (see . A special case of imitation, known as cultural inheritance,
occurs when one or more members of the population learn a novel behavior and
that behavior spreads through the population by imitation. Perhaps the best
evidence for cultural inheritance is that of a species of birds found in
England, commonly known as great tits. In 1921, in England, milk bottles were
still delivered to houses every morning. The bottles were sealed with tin foil.
In that year, great tits in Southampton were first observed removing the tin
foil and drinking the milk. In the 1930s and 1940s, the habit of opening and
drinking the milk spread through England far too quickly to be accounted for by
natural selection. Although it appears the
behavior originated more than once, the most likely explanation is that the
birds observed others opening the milk bottles, and then were able to do it
themselves.
Figure %: Imitation of mobbing behavior in European Blackbirds
