Using digital images in the study of fluctuating asymmetry in the spur-thighed tortoise Testudo graeca
Fluctuating asymmetry has been proposed as a useful noninvasive tool for detecting the influence of the environment on body development. In the present study, we used digital images to estimate the fluctuating asymmetry of the plastron in an isolated Testudo graeca population in Dobrogea, Romania. We extracted data from the photos regarding the area, height, and width of 3 plastron scutes. A total of 155 adult tortoises analysed showed reduced variation in plastron asymmetry and no significant relationship was detected between fluctuating asymmetry and sex or body size. We suggest that fluctuating asymmetry may be an individual trait, with no predictive value at the population level.
Using digital images in the study of fluctuating asymmetry in the spur-thighed tortoise Testudo graeca
Fluctuating asymmetry has been proposed as a useful noninvasive tool for detecting the influence of the environment on body development. In the present study, we used digital images to estimate the fluctuating asymmetry of the plastron in an isolated Testudo graeca population in Dobrogea, Romania. We extracted data from the photos regarding the area, height, and width of 3 plastron scutes. A total of 155 adult tortoises analysed showed reduced variation in plastron asymmetry and no significant relationship was detected between fluctuating asymmetry and sex or body size. We suggest that fluctuating asymmetry may be an individual trait, with no predictive value at the population level.
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