Outline-based Analysis of Sexual Dimorphism in the Shell of the Freshwater Mussel (Margaritifera margaritifera L.)

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Research Paper 01/03/2017
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Outline-based Analysis of Sexual Dimorphism in the Shell of the Freshwater Mussel (Margaritifera margaritifera L.)

Al-Axel O. Joaquino, Danica P. Piñero, Roldan Echem, Cordulo P. Ascaño, Mark Anthony J. Torres
J. Bio. Env. Sci.10( 3), 43-49, March 2017.
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This study was conducted to determine the patterns of sexual dimorphism in the vulnerable species of freshwater mussel Margaritifera margaritifera L. The method of Elliptic Fourier Analysis (EFA) was employed to extract shape information from a total of one hundred (100) points collected from digitized images of the shells. The EFA coordinates where then subjected to statistical analyses such as Kruskall-Wallis and Discriminant Function (DFA) test. Results showed differences in the shape of the lateral sides along the hinges of the shell contour pallial line, the pseudocardinal tooth area and at the umbo. Aside from revealing information on sexual dimorphism, the result of this study is discussed in relation to using patterns of sex differences in shell shape to assess the health of aquatic habitats.


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