Seasonal Dynamics of the Phenotypic Structure of a Natural Epischura baicalensis Sars Population in Terms of Quantitative Morphological Traits
E. L. ERMAKOV, O. O. RUSANOVSKAYA
Irkutsk State University Research Institute of Biology, 664003, Irkutsk, Leninа str., 3
Keywords: Lake Baikal, epischura, quantitative morphological traits, phenotypic structure
Abstract
Seasonаl dynаmics of the phenotypic structure of a natural Epischura baicalensis Sars population from Southern Baikal by reference to the bristles number on the 5th and 6th segments of antenna (BNA), the length of the 5th and 6th segments of antenna (5LAS and 6LAS), cephalothorax length (CL) and the length of the 5 th pair of swimming legs (SLL) was studied. The phenotypic structure in terms of BNA, 5LAS and 6LAS was characterized by presence of bimodality, and in terms of CL and SLL had normal distribution. Seasonаl dynаmics of the arithmetic mean of the whole population was determined by changing of the number of individuals in classes with low and high values of traits. Increasing of the arithmetic mean went along with decreasing of the variability. Influence of temperature parameters on quantitative morphological traits is being discussed.
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