Lechwes and other Antelopes
A detailed taxonomic revision focused my detailed study of the evolution and diversity of lechwe antelopes (Tribe Reduncini) across the wetland archipelago on the Kalahari Plateau (Cotterill 2005): the subject of my doctoral thesis under the auspices of University of Stellenbosch. Research on Zambezian wetlands catalysed this project; it also interfaced with a biogeographical review of how patterns of mammalian speciation has been driven by landscape evolution (Cotterill 2003 - paper reviewing geomorphological influences) which included a detailed study of the Bangweulu Tsessebe, Damaliscus superstes described as new to science in 2003 (Cotterill 2003 - Durb. Mus Novit). Both lechwes and tsessebe can be interpreted as cryptic species, a situation related to the Species Problem, which has manifested in negative impacts of inaccurate and imprecise taxonomy on biodiversity classifications (Cotterill 2003 - species concepts and antelope taxonomy).
Analyses of variation in morphological characters of the Kobus leche complex revealed that the Endangered Upemba lechwe was undescribed (Cotterill 2005). This species was described in 2005 as Kobus anselli in honour of the late W F H Ansell, whose contributions to knowledge of African mammals remain immense.
The discovery of these previously overlooked patterns in mammal evolution can be interpreted as incidents of cryptic speciation, which bear testimony to the dominant role of geological evolution in controlling biotic diversification. The overlooked diversity of reduncine antelopes reveals how the real diversity of Africa's large charismatic mammalian fauna has been underestimated. Adherence to obsolescent Species Concepts is a significant reason for unfortunate deficiencies in contemporary science that undermine the credibility of decisions in conservation (Cotterill 2003, 2005). The scope of this mammalian research has expanded to explorations of the responses of selected African fishes (notably Hydrocynus) to events that reconfigured the topology of drainage systems through the late Cenozoic.
One highlight of this lechwe study was the belated description of the Upemba Lechwe as the new species Kobus anselli. This Critically Endangered species is illustrated in the forthcoming Bovids of the World
Kobus leche (Red lechwe) rams - Okavango Delta. (Photo Jens Kipping)
PhD Thesis
THE EVOLUTIONARY HISTORY AND TAXONOMY OF THE KOBUS LECHE SPECIES COMPLEX OF SOUTH-CENTRAL AFRICA IN THE CONTEXT OF PALAEO-DRAINAGE DYNAMICS. 2006. University of Stellenbosch
These PDFs comprise a condensed edition, typeset to reduce length
Chapter 1 Abstract_ToC_Introduction
Chapter 2 The Natural History of Lechwe Antelopes in a Wetland Archipelago
Chapter 3 Concepts, Particulars, and the Individuality of Species and Speciation
Chapter 4 Geology and Biogeography Combined: Evolutionary Dynamics of the wetland archipelago of south-central Africa
Chapter 5 Dating the Batoka Gorge, and Reconstructing a Model of Drainage Evolution of the Wetland Archipelago
Chapter 6 Phylogeography of the Kobus leche complex
Chapter 7 Morphological Variation in Lechwe Antelopes, and Insights into their Molecular Phylogeny
Chapter 8 Concluding Synthesis
Appendices
WILLIAM FRANK HARDING ANSELL (1923–1996) contributed enormously to
scientific knowledge of African mammals; these include, amongst his many
publications, meticulous faunal syntheses of the mammals of west Africa,
Malawi and Zambia, the exhaustive taxonomy of African mammals (Ansell 1989)
and his classification of the Artiodactyla (1972). Each publication attests to the meticulous
attention paid to the most arcane detail, expunging any mystery that had attached
to a specimen. Frank's boundless energy culminated in an encyclopedic knowledge
of African mammals. His devoted work in the Game Department of Northern Rhodesia,
subsequently Zambia, from 1947 to 1974 created a significant legacy for conservation
as well. Thanks to his thorough collections and meticulous publications, today our
knowledge of the Zambian mammal fauna ranks it among the best known on the African
continent; a monument to Frank’s boundless enthusiasm and commitment to
conservation and mammalogy
Frank Ansell at Chilanga, Zambia 1971 (Photo: Peter Moss)
Publications
Broadley, D. G. & Cotterill, F. P. D. 2004. The reptiles of southeast Katanga, an overlooked 'hot spot'. African Journal of Herpetology 53: 35-61. PDF
Cotterill, F. P. D. 2006. Taxonomy and conservation importance of particular birds occurring in Katanga (southern Congo basin) and its environs. The Ostrich 77: 1-21. PDF
Cotterill, F. P. D. 2005. The Upemba lechwe, Kobus anselli: an antelope new to science emphasizes the conservation importance of Katanga, Democratic Republic of Congo. Journal of Zoology, London 265: 113-132 PDF
Cotterill, F. P. D. 2004. Drainage evolution in south-central Africa and vicariant speciation in swamp-dwelling weaver birds and swamp flycatchers. The Honeyguide. 50: 7-25. PDF
Cotterill, F. P. D. 2003a. Species concepts and the real diversity of antelopes. In: A. Plowman. (Ed.) Proceedings of the Ecology and Conservation of Mini-antelope: An International Symposium on Duiker and Dwarf Antelope in Africa. Filander Verlag: Füürth. pp. 59-118. PDF
Cotterill, F. P. D. 2003b. Geomorphological influences on vicariant evolution in some African mammals in the Zambezi basin: some lessons for conservation. In: A. Plowman. (Ed.) Ecology and Conservation of Small Antelope. Proceedings of an International Symposium on Duiker and Dwarf Antelope in Africa. Filander Verlag, Fürth. pp 11-58. PDF
Cotterill, F. P. D. 2003c. Insights into the taxonomy of tsessebe antelopes, Damaliscus lunatus (Bovidae: Alcelaphini) in south-central Africa: with the description of a new evolutionary species. Durban Museum Novitates 29: 11-30. PDF
Cotterill, F. P. D. 2003d. A biogeographic review of tsessebe antelopes, Damaliscus lunatus (Bovidae: Alcelaphini), in south-central Africa. Durban Museum Novitates 28: 45-55. PDF