ABSTRACT

Marine plants and animals, especially those from tropical waters are often brilliantly coloured and provide a pageant of great beauty, and bright colouration is widespread in both sessile and non-sessile invertebrates. These colours are common in species inhabiting shallow waters, and appear not only in animals exposed to bright light, but also in those living in dark areas where colours are visible only with artificial illumination. The marine organisms also display many examples of colour patterns. The colour characteristics of organisms serve various purposes and are the result of several different processes. Pigments in invertebrates may be involved in physiological processes and their distribution and functions seem to differ between invertebrate groups.

This review article discusses the metabolites, chemical and biological processes, and environmental factors responsible for the bright colours of some marine invertebrates, the evolution and “speculations” of their functions and the significance of colours present in them. Metabolites identified are classified according to “chemical classes”, and some of the chemical structures of pigments and secondary metabolites are illustrated.