Enigmatic Unicellular Protista: Are they Really Enigmatic? The Algae Case

Abstract

The Oxford Dictionary describes “enigmatic” as “puzzling”. This contribution could perhaps then be retitled. Are there any truly puzzling algae? Such algae would be those that are distinguished from their presumptive relatives by differences in their physiological, biochemical, structural/ultrastructural and other cellular and molecular features such that their phylogeny and evolution does not seem to fit into any obvious pattern. Frequently phycologists are tempted to place an algal oddity in a pigeon-hole ( = taxon ) before all the data are assembled or sufficient knowledge is available to make and informed decision. These algae often do not seem to fit into the existing delineations of the higher taxa, particulary those of Class and Division. This lack of a comfortable fit or pigeon hole is often a result of our own lack of flexibility, our own slowness in assembling the necessary data needed to make the informed decision, our reluctance to embrace new techniques of analysing the questions and to challenge established dogma. Much of this is steeped in historical precedent. Current algal classification has its origins in the system proposed by Pascher (1931) some 65 years ago. The tools available at that time were those of light microscopy and very rudimentary and basic chemical analyses. Later, improved methods of chemical analyses provided a measure of increased detail and refinement. These provided the data bases upon which the system was built and subjected to minor modifications. The next level of improved sophistication, applied in the early 1960’s was that of electron microscopy and greatly improved chemical analyses brought about by the physical techniques of nmr and mass spectrometry.