Biology Reference
In-Depth Information
(a)
(b)
Fig. 3.12
Two species of sticklebacks. (a) Nine-spined sticklebacks often rely on public
information when choosing foraging sites, whereas (b) three-spined sticklebacks rely
more on personal sampling of alternative options. Photos © Kevin Laland.
Copying and learning facilitation
Whiten
et al
. (2005) tested whether captive chimpanzees
Pan troglodytes
copied the
actions of others. In one group, they trained one individual to obtain food by poking a
stick into an apparatus to release a food item. In another group, one individual was
trained to adopt a different method to obtain food from the same apparatus, by using the
stick to lift up some hooks to release the food. When these two demonstrators were
returned to their respective groups their companions observed them at work and then
most of them adopted the particular technique seeded in their group (either poking or
lifting). By contrast, no chimpanzees mastered either tool using technique in a third
population that lacked a local expert. This group, with no demonstrator, severed as a
control for possible effects of asocial learning.
Thornton and Malapert (2009) tested whether a novel food acquisition technique
could spread through a wild population in a study of meerkats
Suricata suricatta
in the
Northern Cape, South Africa. Again, food could be obtained from an apparatus in one
of two ways: either by climbing some steps and ripping the cover off a box, or by going
through a cat-flap at the bottom of the box. In three groups, one individual was trained
to perform the 'stairs' technique, in another three groups one individual was trained to
perform the 'flap' technique, and in a further three control groups no individual was
trained. The results showed that the two experimental groups were more likely to gain
food from the box and that naïve individuals tended to adopt the technique of their
demonstrator, either after observing it or scrounging food while the demonstrator fed
from the box. In this case, naïve individuals might not necessarily have copied the
actions of demonstrators but simply have had their attention drawn to either the stairs
or the flap and then have learnt themselves how to access the food.
Chimpanzees and
meerkats learn
foraging tricks
from others
Local traditions
Social learning could lead to local traditions. For example, in some wild populations
chimpanzees forage for ants by using a long wand. A chimp waits until many ants have
gripped the wand, then it uses the other hand to wipe them off and transfer them to its
