Sexual size dimorphism in Ground Beetles and its modeling in latitude gradient Primary tabs

Abstract

Large-scale systematic patterns of variation lie in the heart of organismic biology and have interested biologists ever since the beginning. These are most obvious in terms of body size, probably the single most important quantitative trait of an individual. In this relation Ground Beetles are poorly studied, though they are regarded to be sensitive to environmental changes and are accepted bioindicators. Beetles were sampled in 8 provinces of Russia, situated at different latitudes. We measured elytra length in six paleartic eurytopic species of carabids. We used mixed linear models to infer the mean latitude effect on size and sexual dimorphism of females and males. Regression coefficients in both sexes were negative and differed in different species. In C. cancellatus, C.hortensis, P. niger modulus of regression coefficients were larger in females, then, in that species females were more variable than males. In C. granulates and P. melanarius modulus of regression coefficients were larger in males, then, in those species males were more variable in latitude gradient. It is noteworthy that species, sharing the same ecological niches, had different strategies in realizing sexspecific body size variation in latitude gradient. E. g., C. granulatus -C. cancellatus, P. niger -P. melanarius. In general body size decreased in latitude gradient both in females and males. Shifts were steeper in Carabus species, than in Pterostichus. Despite SSD occurred in some analyzed latitudes and mainly at the margins of area, modeling results did not confirm opinion that SSD systematically changes in latitude gradient.

Modeling sexual differences of body size variation in ground beetles in geographical gradient (The case study in Pterostichus oblongpunctatus Fabricius, 1787)

“…Despite of textbook attribution to ecosystems of Europe [48], given species is found abundant further in Palearctic. Conducted research provides insight on their presence and abundance in Mesouralic and Siberian ecosystems [49]. All given geographic areas of research are ecosystems with homogenous arboreal composition, characterized by a single dominant species even in non-climax ecosystems and cover large geographic span.…”

Sexual size dimorphism variation in altitude gradients in ground beetles (Coleoptera, Carabidae)

“…Since the patterns of sexualdimorphism (SD) for different characters in individualsof the same species can vary [1], six morphometric characters of ground beetleswere taken in our analysis. Morphometric measurementswere carried out under an MBS-9 binocularmicroscope at a magnification of 1 × 8.…”

“…Additionally, linear modeling detected environmental factors affecting morphometric structure in carabid assemblages [4][5][6][7]. No less attention was paid to sexual size dimorphism and its variation in species studied [8,9]. In this paper, we continue the theme of body size and sexual size dimorphism variation in altitude gradient.…”

“…The subject of our investigations is ground beetles. As the rule, SSD in them is female-biased [1]. Carabids are widely distributed, allowing to examination of large data arrays.…”

Sexual Dimorphism of the Pterostichus Melanarius Ill. (Coleoptera, Carabidae) and the Conditions of Its Manifestation

“…У жужелиц регистрируется характерный для артропод ПД с бóльшими размерами самок [5]. Было также показано, что значение ПД у них не статично, а меняется в зависимости от внешних условий [6][7][8]. Цель данной работы -оценить изменчивость ПД у жужелицы Pterostichus melanarius Ill. под влиянием таких факторов, как место обитания в ареале, степень урбанизации и освещенности биотопа.…”