A Pluralistic Analysis of Character Release in Pumpkinseed Sunfish (Lepomis Gibbosus)

Abstract

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Morphological variation of pumpkinseed (Lepomis gibbosus) with emphasis on allometry

“…We defined the Akgedik Reservoir (4800) as a lentic habitat, which was formed recently from the neighboring Sarıçay Stream (4801). as presented in this study suggests that environmental changes seem to be responsible for most of the variation, as suggested by Robinson et al (2000), Tomeček et al (2005), and Bhagat et al (2011b). In addition to this, clustering geographically distinct localities (Akgedik Reservoir and Hayrabolu Pond, as shown in Table 3) with different stories of introduction decreases the likelihood of genetic effects on morphometry and favors environmental effects.…”

The Evolution of Resource Specialization through Frequency‐Dependent and Frequency‐Independent Mechanisms

“…If one wants to relate our results to real organisms these features have to be studied. Considerable effort has been made with respect to the shape of the trade-off (Benkman 1993;Schluter 1993Schluter , 1995Robinson et al 2000) though is is only recently that more powerful methods are developed to infer the shape from empirical data (Hatfield and Schluter 1999;O'Hara Hines et al 2004). The tendency in the cited studies is that trade-offs are indeed rather strong than weak, which fulfils a necessary requirement for diversification in our theory.…”

Adaptive individual differences within single populations

“…However, bluegill sun¢sh have been introduced to some lakes in the north-eastern US, providing a natural experiment to test this possibility. We examined two large lakes in the Adirondack mountain region with introduced bluegill, and in both cases the pumpkinseeds were con¢ned to the littoral zone, as in all mid-western lakes (Robinson et al 1998).…”

“…Pumpkinseeds inhabited the open water of 12 out of 12 large lakes (491ha) and 10 out of 14 small lakes (533 ha) that were censused (Robinson et al 1998).…”

“…The di¡erences were statistically signi¢cant in 10 out of the 12 large lakes and 5 out of the 10 small lakes. Figure 3 shows examples for three large lakes, which range from very modest di¡erences to almost no overlap in morphological space (Robinson et al 1998).…”