Landmark-Based Geometric Analysis In Describing The Body Shape Variation In Three Female Population Of Sardinella tawilis (Clupeiforms: Clupeidae: Clupeinae) from Taal Lake, Philippines

Author(s): Osmerando Jr. Alcantara
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Institution or organization of origin: Tanauan City Integrated High School
Country: Philippines


The study utilized landmark-based geometric morphometrics to identify the body shape variation of Sardinella tawilis populations within three spawning sites namely, Agoncillio, Balete, and Cuenca in which thirty samples were each collected from the respective areas. The samples were digitized and landmarked using 18 landmark points thus the relative warp (RW) that was derived from the populations were obtained. Significant results for the variation of the three populations were identified using One-Way ANOVA, Tukey’s Pairwise Comparison, Mann-Whitney and Kruskal Wallis. Significant differences were found between the collected samples, they mostly varied in meristic measurements which were taken from the specimen’s parts such as the head, standard length, eye diameter, and length of fins alongside with the curvature of the body, compression and decompression at the mid-section or the belly, dorsal and ventral side and the posteriormost aspect of the neurocranium. The physico-chemical parameters of each spawning site were also considered in the study as it plays an important role in regards to ‘tawilis’ body morphology. Using the results from the study the researchers aim to identify the most suitable and preferred spawning ground for S. tawilis which will enable them to reproduce freely and efficiently through distinguishing its body shape variation. Through this, the diminishing population of Sardinella tawilis can be saved by planning conservation strategies and techniques relative to their physiological and morphological functions.

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