Mean snout-vent length and (relative) abdomen length was greater in females than males, whereas absolute and relative mean head size, fore – and hindlimb length was larger in males. These patterns suggest that body size may reflect sexual evolutionary conservatism. The lizards are smaller at
higher elevations or in colder climates, representing the converse of Bergmann’s rule. Absolute differences in female body size among taxa are not equal to the male differences among taxa. This results in a slope less than one when male size is regressed on female size, which allows rejection of Rensch’s LDK378 cell line rule for this group. The female body size elevation-related cline was steeper than the corresponding male cline. Litter sizes were both smaller and less variable at higher elevations. These elevational clines remained after application of phylogenetic comparative methods, indicating that ecological processes play a more important role than phylogeny in shaping patterns of size and reproductive variation in these lizards. It is suggested that seasonal activity and temperature are important environmental factors Sorafenib clinical trial that contribute to the
converse Bergmann’s cline, while fecundity selection in females and sex-specific differential-plasticity likely explain why patterns do not conform to Rensch’s rule. “
“Cryptic behavior and unpalatability are common defensive strategies that occur in different taxonomic groups, but
the effectiveness of these defensive strategies is context dependent, varying with predator type and co-occurring species. We tested this assumption by measuring the mortality rates of Eupemphix nattereri (cryptic behavior) and Rhinella schneideri (unpalatable) tadpoles in association with the predatory fish Oreochromis niloticus (vertebrate) and the dragonfly larvae of Aeshna sp. (invertebrate). We designed a second experiment to evaluate whether fish predators are capable of Unoprostone learning to avoid unpalatable prey once they have encountered it. Our results showed that fish preyed selectively on palatable tadpoles, avoiding unpalatable tadpoles and that the odonate larvae were more efficient in preying on the more active unpalatable tadpoles and less efficient in capturing those tadpoles that presented cryptic behaviors. Additionally, our data suggest that the antipredator traits of tadpoles can interact with each other, with cryptic tadpoles showing lesser mortality when co-occurring with unpalatable tadpoles and odonate predators. Unpalatable tadpoles also increase the mortality of cryptic tadpoles in the presence of experienced fish predators. These prey traits interact in modifying the prey preference of the predator, which constitutes a prey-induced trait-mediated interaction (TMI).