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Species color and color pattern vary geographically contributing to environmental tolerance of the species to the fluctuating climate. In a constantly changing environment, the population remains polymorphic, when individuals that are not acclimated to the current environment can survive adverse time periods. Factors influencing color morph frequencies in populations affect spatial variation through local adaptation, which is in turn linked to large‐scale environmental gradients. The influence of environmental factors has not been adequately studied in many polymorphic organisms where the influence of sexual selection on the persistence of polymorphisms is widely recognized. We hypothesized that different color morphs of sand lizard are distributed throughout the Palearctic depending on different environmental conditions. The goal of this study was to examine if the range of morph composition in a color polymorphic lizard can be explained by geographic and climatic variation in the Palearctic. We used publicly available data on sand lizard occurrence from the Global Biodiversity Information Facility and environmental variables from WorldClim and SEDAC databases. We categorized sand lizards' photos to 10 discrete color morphs based on color and color pattern variation. We predicted the color morph distribution using maximum entropy models. We found that variations in morph distributions were mostly related to temperature seasonality, precipitation, elevation, and anthropogenic activities. Our findings support the relationship between environmental conditions and color morph distribution, implying that environmental selection acts differently on color morphs, most likely in conjunction with sexual selection.

In the present study, an attempt was made to document the spatial distribution and diversity inventory of macro-benthic fauna from 21 sampling stations of the Indian Sundarbanfor a period of six months from November 2014 to April 2015. A total of 1,871 individuals belonging to 35 species were recorded which comprised 12 species of molluscs, 20 species of crustaceans, one species each of xiphosurid, sea anemone and fish. The frequency analysis of species revealed that the most dominant species were Telescopium telescopium and Tubuca rosea among molluscs and crustaceans, respectively. The density analysis of the species showed that Pirenella cingulata and T. rosea had maximum values among molluscs and crustaceans, respectively. The average values of Shannon-Wiener diversity index, Simpson diversity index, dominance index and Margalef diversity index were found to be 2.712, 0.888, 0.111 and 4.513, respectively.