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Do molecules matter more than morphology? Promises and pitfalls in parasites

Published online by Cambridge University Press:  09 June 2011

S. L. PERKINS ,
E. S. MARTINSEN  and
B. G. FALK
S. L. PERKINS*
Affiliation:
Sackler Institute for Comparative Genomics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
E. S. MARTINSEN
Affiliation:
Smithsonian Conservation Biology Institute, National Zoological Park, Washington, D.C. 20008, USA
B. G. FALK
Affiliation:
Sackler Institute for Comparative Genomics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA Richard Gilder Graduate School, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
*
*Corresponding Author: Tel: 01-212-313-7646 Fax: 01-212-313-7819. E-mail: perkins@amnh.org
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Summary

Systematics involves resolving both the taxonomy and phylogenetic placement of organisms. We review the advantages and disadvantages of the two kinds of information commonly used for such inferences – morphological and molecular data – as applied to the systematics of metazoan parasites generally, with special attention to the malaria parasites. The problems that potentially confound the use of morphology in parasites include challenges to consistent specimen preservation, plasticity of features depending on hosts or other environmental factors, and morphological convergence. Molecular characters such as DNA sequences present an alternative data source and are particularly useful when not all the parasite's life stages are present or when parasitaemia is low. Nonetheless, molecular data can bring challenges that include troublesome DNA isolation, paralogous gene copies, difficulty in developing molecular markers, and preferential amplification in mixed species infections. Given the differential benefits and shortcomings of both molecular and morphological characters, both should be implemented in parasite taxonomy and phylogenetics.

Keywords

Integrated taxonomymolecular systematicscryptic species
Type
Research Article
Information
Parasitology , Volume 138 , Special Issue 13: Systematics as a cornerstone of parasitology , November 2011 , pp. 1664 - 1674
Copyright
Copyright © Cambridge University Press 2011

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