Biology session

Morphological and genetic data are widely employed in characterizing the diversity of organisms. This exploration of diversity is particularly crucial for endangered populations, as it aids in identifying significantly distinct populations that may be threatened by genetic deterioration. Without such information, conservation efforts become more challenging to plan.

In the past, the study of population divergence primarily relied on morphological traits. However, genetic and genomic methods have become increasingly accessible and prevalent. Even before the widespread use of molecular genetic techniques, conservation biologists recognized the importance of low diversity or potentially inbred populations. Consequently, the assessment of fluctuating asymmetry (FA) emerged as an indicator. FA, which pertains to asymmetry in morphological traits in bilaterally symmetric animals, has been associated with environmental or genetic factors that perturb embryonic development and is linked to the extent of asymmetry in basic morphological traits.

In this study, we compared the results of differentiating individuals and populations of the endangered Greek Meadow Viper (Vipera graeca) based on morphological and RADseq data. Additionally, we investigated whether there is a correlation between FA and genomic inbreeding values. Furthermore, we examined the influence of habitat size and temperature on the latter values.

We collected morphological data from 305 viper individuals across 16 populations, focusing on four symmetric morphological traits. Furthermore, we obtained RADseq SNP data from 72 individuals belonging to these populations. To assess morphological and genetic similarity, we constructed Euclidean and Nei distance matrices and employed clustering methods. We calculated three indices for characterizing FA (FA1, FA11, FA12) and measured genomic inbreeding using Fis values derived from genomic data.

Based on morphological traits, individuals did not cluster according to populations, while the genetic data clearly separated most populations into distinct branches. No correlation was found between morphological and genomic distance matrices among populations. FA values for individuals and populations did not show a correlation with genomic Fis values, but both were influenced by the latitudinal position of populations.

In conclusion, in the case of the Greek Meadow Viper, the examined morphological traits are not suitable for distinguishing populations, whereas genomic data are highly effective for this purpose. The presence of FA is likely influenced not by the genetic state of populations but rather by environmental factors that disrupt embryonic development, such as climatic conditions.