Objective 3: Trends in use of “life history” and “ecotype”
Our literature search yielded 120 articles, including 46 that focused on sticklebacks, 61 on PST, and 13 on lampreys (Table 2). Nine articles found by the Web of Science literature search were omitted from our analyses because these papers focused on life stage differences rather than intra-specific phenotypic differences. Journals with a general focus on organismal biology and ecology tended to use the term(s) “life history / life histories”, whereas journals focusing on evolution and genetics tended to use the term “ecotype(s)” (Figure 1). Studies that used the term ecotype(s) tended to report a genetic basis for the phenotypic differences (Figure 2). The literature on sticklebacks tended to use both life history / life histories and ecotype(s) in equal amounts (Figure 3A), whereas the literature on PST and lampreys tended to use life history / life histories to a greater extent (Figures 3B and 3C). Taken together, this information suggests that sticklebacks have been a field and laboratory model for evolutionary and genetic research, whereas PST have tended to be the focus of fisheries-related research and management, and lampreys have experienced comparatively much less research.