Social and socio-
Ontogeny and symbolism
Cognitive abilities in a comparative perspective
Andrew Lock and Michael Colombo
Recent studies of non-human animals indicate that cognitive processes mediate many areas of their behaviour. A number of human cognitive systems, and their properties þ for example memorial processes, categorical auditory and visual perception þ appear to have quite deep phylogenetic roots. It is not yet possible, however, to provide a precise evolutionary classification of these systems, for ecological factors play as large a role in the elaboration of an animal's cognitive abilities as does its phylogenetic status. Thus, many 'indices' that have been proposed as differentiating phylogenetic groups in terms of their 'learning abilities' or 'intelligence' have not been substantiated: initially promising proposals have been confounded by animals from 'lower' taxa showing 'unexpected' levels of ability in sensory domains relevant to their ecological niches. A restricted focus on primates, however, does tend to show an improvement in levels of performance from prosimians to Great Apes on tasks such as reversal learning; and it seems likely that these changes are based in differences in the underlying cognitive abilities and strategies these species employ.
The ability to form concepts has been shown for a number of non-human species. Most of these concepts have physical instantiations. Conflicting claims are made regarding the possession of the concepts of 'same' and 'different'. These appear to be absent in pigeons and goldfish; their status in monkeys is subject to dispute; they are quite well elaborated in the Great Apes, especially in chimpanzees, where most of the experimental effort has been focused. In this last-mentioned species, 'same-different' judgements extend into areas of analogy and transitive inference, which are perhaps closer to reasoning abilities than merely conceptual ones.
Observational learning (or imitation) has been divided into
the categories of social facilitation, stimulus enhancement,
and imitative copying. The last of these is largely confined
to the Great Apes; whereas the other two occur across all the
primate groups. Imitative copying is less developed in the
Great Apes than in humans, and 'teaching' plays little or no
role in the transfer of skills. Chimpanzees are capable of
adaptive novel responses in a problem-solving context; but
these are more possible for them in some situations than in
others. Chimpanzees and orang-utans show self-recognition
when confronted with a mirror; but all other primates tested
tend to react to mirrors socially, as if they were confronting
There are some Piagetian-inspired investigations of
comparative cognitive abilities. The Great Apes appear to
reach sensorimotor Stage 6 in object permanence, spatial
concepts, imitation, and the understanding of causality.
Piagetian investigations of possible representational
intelligence have proved disappointing to date.