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| Our understanding of the complex world of cichlids is moving
forward at a rapid rate. In this issue, we present three articles
exploring the complexity of diversity in cichlids from both sides of
the Atlantic. Each of these investigations hinges on understanding what
is a phylogenetically informative character (those characters which
illuminate evolutionary ancestry) versus what is the product of
convergence (characters which represent independent evolutionary
solutions to the same problem). So, for instance, Ad Konings argues in his article on the elongate mbuna from Lake Malawi that tooth structure and feeding styles are evolutionarily conservative and reflect the evolutionary relationships of the group. In other words, those individuals which share particular tooth structure (and corresponding feeding style) are more closely related. The fact that they are all elongate is the result of convergence. Hence, being elongate is not a true indictor of relationships. However, that does not mean, nor does Ad imply, that being elongate is not important, nor interesting. Quite the opposite. It means that being elongate has been selected for multiple times, in multiple lineages of mbuna. It pays to be long and slim for certain rock-dwelling cichlids in Lake Malawi. For Lake Tanganyika, Patrick Tawil uses subtle color differences and such morphological characters as head shape to examine the Julidochromis regani group. We do not yet fully appreciate the meaning of these subtle differences, but one day we will. Similarly, Willem Heijns presents Oldrich Rícan’s investigation of the New World heroine cichlids. This study uses not only morphology, but also modern molecular tools to reveal new information about these popular cichlids. This interplay of evolutionary ancestry and convergent evolution is the artistic force that has produced so many, incredible cichlids, which we now enjoy. I encourage you to appreciate the dynamic tension between these forces being played out in your fishes. An important message from each of these authors is how essential it is that cichlid aquarists be discriminating in their cichlid acquisitions. Be concerned about where your fish come from. Pay attention to locality names, try hard not to mix together individuals of different populations and be sure to pass on this information as you pass on the offspring of your successful spawnings. There is beauty and wonder in each and every natural form of cichlid.
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Ron Coleman, Editor
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