Biology subjects

Smolinsky, R.

Publications and source records attributed to Smolinsky, R..

3 recordsLinked to original sources

bioRxiv2022

High predation risk decimates survival duringthe reproduction season

O_LIPredators attack conspicuous prey phenotypes that are present in the environment. Male display behaviour of conspicuous nuptial colouration becomes risky in the presence of a predator, and adult males face higher predation risk. High predation risk in one sex will lead to low survival and sex ratio bias in adult cohorts, unless the increased predation risk is compensated by higher escape rate. C_LIO_LIHere, we tested the hypothesis that sand lizards (Lacerta agilis) have sex-specific predation risk and escape rate. We expected the differences to manifest in changes in sex ratio with age, differences in frequency of tail autotomy, and in sex-specific survival rate. C_LIO_LIWe developed a statistical model to estimate predation risk and escape rate, combining the observed sex ratio and frequency of tail autotomy with likelihood-based survival rate. Using Bayesian framework, we estimated the model parameters. We projected the date of the tail autotomy events from growth rates derived from capturerecapture data measurements. C_LIO_LIWe found statistically stable sex ratio in age groups, equal frequency of tail regenerates between sexes, and similar survival rate. Predation risk is similar between sexes, and escape rate increases survival by about 5%. We found low survival rate and a low number of tail autotomy events in females during months when sand lizards mate and lay eggs, indicating high predator pressure throughout reproduction. Our data show that gravid females fail to escape predation. C_LIO_LIThe risks of reproduction season in an ectotherm are a convolution of morphological changes (conspicuous colouration in males, body allometry changes in gravid females), behaviour (nuptial displays), and environmental conditions which challenge lizard thermal performance. Performance of endotherm predators in cold spring months endangers gravid females more than displaying males in bright nuptial colouration. C_LI

ecology↗

bioRxiv2020

Tadpoles of the hybridising fire-bellied toads (Bombina bombina and B. variegata) differ in their susceptibility to predation

The role of adaptive divergence in the formation of new species has been the subject of much recent debate. The most direct evidence comes from traits that can be shown to have diverged under natural selection and that now contribute to reproductive isolation. Here, we make the case for differential adaptation of two fire-bellied toads (Anura, Bombinatoridae) to two types of aquatic habitat. Bombina bombina and B. variegata are two anciently diverged taxa that now reproduce in predator-rich ponds and ephemeral aquatic sites, respectively. Nevertheless, they hybridise extensively wherever their distribution ranges adjoin. We show in laboratory experiments that, as expected, B. variegata tadpoles are at relatively greater risk of predation from dragonfly larvae, even when they display a predator-induced phenotype. These tadpoles spent relatively more time swimming and so prompted more attacks from the visually hunting predators. We predict that genomic regions linked to high activity in B. variegata are barred from introgression into the B. bombina gene pool and thus contribute to gene flow barriers that keep the two taxa from merging into one.

ecology↗

bioRxiv2019

Quantifying colour difference in animals with variable patterning

Colour pattern influences behaviour and modifies survival of organisms through perception of light reflectance. Spectrophotometric methods used to study colour navigate between precision and accuracy of reflectance across wavelengths, while photographic methods are generally used to assess the complexity of colour patterns. Here, we compare how colours characterised using point measurements (simulating spectrophotometry) on the skin of a sand lizard (Lacerta agilis) differ from colours estimated by clustering pixels in a photograph of the lizards body. We found that point measurements adequately represented the dominant colour of the lizard; however, where colour patterning influenced measurement geometry, image analysis outper-formed point measurement as regards stability between technical replicates on the same animal. The greater colour variation established from point measurements increased further under controlled laboratory illumination. Both methods revealed lateral colour asymmetry in sand lizards. We conclude that studies assessing the impact of colour on animal ecology and behaviour should utilise hyperspectral imaging, followed by image analysis that encompasses the whole colour pattern.

ecology↗