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Macroevolutionary Patterns of Male Reproductive Investment in a Clade of Parasitic Hermaphrodites
Faculty Publications from the Harold W. Manter Laboratory of Parasitology
  • David Zamparo, University of Toronto
  • Deborah A. McLennan, University of Toronto
  • Daniel R. Brooks, University of Toronto
Date of this Version

Published in the Journal of Parasitology (June 1999) 85(3): 540-544. Copyright 1999, the American Society of Parasitologists. Used by permission.


The Eucestoda is particularly relevant for questions concerning reproductive investment in male gametes because no other parasitic group displays such diversity in testis size and number within and among species. This diversity has long been used as a valuable taxonomic character, but few researchers have ever investigated its evolutionary significance. In this paper we investigate the evolution of testis number and size within Rhinebothroides (Platyhelminthes: Eucestoda). Our comparative, phylogenetic analysis revealed that overall allocation to male functions, as measured by relative testicular area, does not change within the clade, even though the packaging of that investment in numerous testes is highly variable within, and diverse among, members of the group.

Citation Information
David Zamparo, Deborah A. McLennan and Daniel R. Brooks. "Macroevolutionary Patterns of Male Reproductive Investment in a Clade of Parasitic Hermaphrodites" (1999)
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