Shorter telomeres are associated with shell anomalies in a long‐lived tortoise

• Published in: Journal of zoology (1987) Vol. 323; no. 1; pp. 67 - 75
• Main Authors: Mira‐Jover, Andrea, Rodríguez‐Caro, R. C., Noguera, J. C., Fritz, U., Kehlmaier, C., García de la Fuente, M. I., Giménez, A., Graciá, E.
• Format: Journal Article
• Language: English
• Published: London Blackwell Publishing Ltd 01.05.2024
• Subjects: Aging; Anomalies; Biological age; Body condition; Capture-recapture studies; ectotherms; fitness; Growth rate; longevity; Ontogeny; Reptiles; Reptiles & amphibians; Senescence; Sex; shell anomalies; telomere length; telomere maintenance; Telomeres; Testudines; Testudo graeca; Tortoises; Turtles
• ISSN: 0952-8369; 1469-7998
• DOI: 10.1111/jzo.13154

Age‐related telomere length (TL) variation is relatively well‐described for mammals, birds and other model organisms. Nevertheless, it remains largely unknown in ectotherms, especially turtles and tortoises, which are extremely long‐lived species with slow or negligible senescence. In this study, we described TL dynamics in wild spur‐thighed tortoises (Testudo graeca), one of the chelonian species with the lowest aging rates. By combining cross‐sectional (single) and longitudinal (capture–recapture) samplings, we assessed the relationship between TL and individual characteristics (sex, age, individual growth rate, body condition index, presence of shell anomalies). We did not find any association between TL and sex, individual growth rate, or body condition. However, the relationship with age remains uncertain, likely due to the complex dynamics of TL over time. Interestingly, shorter telomeres correlated significantly with shell anomalies, which are usually assumed as a fitness proxy for reptiles. Overall, our results suggest TL as a potential indicator for ontogenetic studies on tortoises, while its utility as a marker of biological age appears limited. Telomere length and its shortening/maintenance/elongation are proposed as a biological indicator of aging, longevity or risk of diseases in many taxa. However, for reptiles, telomere dynamics are not clearly defined. Here, working with wild populations of Testudo graeca, we assess the relation between telomere length and a set of individual characteristics and we evaluate time effect with a capture–recapture experiment. Only the presence of shell anomalies is correlated with shorter telomeres, suggesting telomere length as a potential indicator of ontogenic development while its utility as a marker of biological age appears limited.