About 50% of African cichlid species have been described. Little is known about cichlid
ecology, behaviour or about the evolution and interactions of communities. Nevertheless,
trends which provide an insight into cichlid life histories, into evolutionary alternatives
and into behavioural alternatives which may be followed during the life time of these
fishes are emerging. Cichlids which spend their entire life history in a single habitat
belong to species flocks that have speciated greatly. In contrast, those groups which live
in a variety of habitats during their life history have speciated little. Despite the
trophic specializations that have occurred among cichlids, many and perhaps all species,
have the ability to feed upon alternative food resources. They do so by switching or by
markedly modifying their behaviour and all are particularly opportunistic. The extensive
adaptive radiation of cichlids with regard to those attributes of morphology and behaviour
that are associated with survival and growth, is apparently not matched by similar radiations
in reproductive behaviour. The perceived evolutionary conservatism with regard to reproductive
behaviour is attributed to the effects of stabilizing selection, but this still needs to be
tested. The constraints of stabilizing selection appear to be lifted with regard to coloration.
If colour is an important component of the specific-mate recognition system then it should
also be subjected to stabilizing selection so the readiness with which colour variation occurs
within and between populations needs explanation. Parental care in cichlids has followed a
variety of evolutionary alternatives, all of which are geared to improve the chances of
survival of offspring in their specific micro-habitats.