Nice open access paper: Takahashi Tetsumi & Koblmüller Stephan (2011) - The Adaptive Radiation of Cichlid Fish in Lake Tanganyika: A Morphological Perspective. SAGE-Hindawi Access to Research - International Journal of Evolutionary Biology. Volume 2011, Article ID 620754, 14 pages
Lake Tanganyika is the oldest of the Great Ancient Lakes in the East Africa. This lake harbours about 250 species of cichlid fish,
which are highly diverse in terms of morphology, behaviour, and ecology. Lake Tanganyika’s cichlid diversity has evolved through explosive speciation and is treated as a textbook example of adaptive radiation, the rapid differentiation of a single ancestor into an array of species that differ in traits used to exploit their environments and resources. To elucidate the processes and mechanisms underlying the rapid speciation and adaptive radiation of Lake Tanganyika’s cichlid species assemblage it is important to integrate evidence from several lines of research. Great efforts have been, are, and certainly will be taken to solve the mystery of how so many cichlid species evolved in so little time. In the present review, we summarize morphological studies that relate to the adaptiveradiation of Lake Tanganyika’s cichlids and highlight their importance for understanding the process of adaptive radiation.
http://downloads.sage-hindawi.com/journ ... 620754.pdf