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“Life histories” is a more appropriate term than “ecotypes” to describe ocean- and stream-maturing Pacific lamprey Entosphenus tridentatus
  • Benjamin Clemens,
  • Carl Schreck
Benjamin Clemens
Oregon Department of Fish and Wildlife, Oregon State University
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Carl Schreck
US Geological Survey, Oregon Cooperative Fish and Wildlife Research Unit, USGS
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The scientific literature includes a plethora of terms to denote within-species phenotypic diversity (e.g., morphotypes; ecotypes; ecomorphotypes; ecophenotypes; polymorphisms; and life histories). Here we discuss a particular situation in which different terms (ecotypes and life histories) have been used to describe the same within-species diversity of adult Pacific lamprey Entosphenus tridentatus, note an important challenge in using “ecotypes”, and conclude with a recommendation to use “life histories” to describe the ocean- and stream-maturing forms of Pacific lamprey.