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The behavioural responses of predator-naïve (laboratory-born), predator-experienced (laboratory-born but with short-term experience with predators), and wild-caught (with long-term experience with predators in natural settings) tadpoles of Sphaerotheca breviceps to carnivorous predatory tadpoles of Hoplobatrachus tigerinus was studied in the laboratory. The predator's stimulus solution (kairomones) was used to simulate predation threat. All S. breviceps tadpoles (i.e., predatornaïve, predator-experienced and wild-caught) exhibited behavioural antipredator responses, i.e., reduced swimming activity and time spent swimming, and had a higher burst speed in response to water-borne kairomonal cues of predators. Wildcaught tadpoles showed stronger responses than predator-naïve and predator-experienced tadpoles and the latter exhibited stronger responses than predator-naïve tadpoles. Our study thus suggests that antipredator behaviour in these tadpoles is basically innate. Furthermore, the enhanced antipredator behaviour of wild-caught tadpoles indicates that learning is involved. [ABSTRACT FROM AUTHOR]

The article discusses the study on population densities of the forest lizard, Calotes rouxii, found in Gobral village, Uttar Kannada, Karnataka in south-western India. Statistical analysis was done on data gathered for four consecutive days in nine transects, recording a mean number of C. rouxii of 61.5 lizards in an area of 1.125 hectares. The cloudy weather on the first and fourth day is attributed for the low number encountered. A low percentage of C. rouxii was recorded at lower altitude, while a higher percentage was noted at altitude between 600-1,200 meters. Iy also suggests that aside from altitudinal range, abundance may also be dependent on the type of vegetation, habitat, and climatic conditions.