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We carried out a study on age determination for Spanish red deer (Cervus elaphus hispanicus) from growth marks in dental cementum. We investigated the age at which the first growth layer and first rest line appear in cementum of incisors (I1), molars (M1), and canines (C), and explained how to interpret these marks to determine age. We evaluated accuracy and precision of aging with rest lines of different tooth types. Age was estimated using a standardized counting method and a linear regression analysis, both based on rest-line number in permanent teeth of red deer aged between 4 and 44 months. The first growth layer occurred after dental eruption in all teeth studied. The first rest line appeared at 6 months in molars (M1) and at 15 months in incisors (I1). The second rest line appeared at 18 months in molars and incisors. Each consecutive rest line represented one year more in animal age. Subsequent analysis showed that canines do not give an accurate estimation of the real age. Molars and incisors did not yield the same values for age estimation. Molars gave the best results, aging 75% of animals correctly, while only 49% were aged correctly using incisors. Nevertheless, within a one-year confidence interval, 99% of the animals were aged correctly using molars, versus 86% using incisors. We suggest using the first lower molar for deer aging in Sierra Morena. Use of regression should be preferred to the standardized counting method for age determination when using incisors. [ABSTRACT FROM AUTHOR]

We aim to extend our understanding of the seasonal formation of cellular cementum, and its functional relationships in fallow deer (Dama dama) from Mediterranean ecosystems, in order to achieve reliable cementochronology applications. We provide a specific reference for fallow deer in a specific ecosystem, as needed for forensic, paleontological and wildlife ecology research. A semi-quantitative rating of the last outermost increment deposited in the cellular cementum interradicular pad of the lower first molar (M 1), together with the knowledge of the animal's date of death, provided the methodological basis of this study. We also analyzed the occurrence of each cementum state by season, as well as the influence of the photoperiod and seasonal diet quality variations, using indices such as cell wall digestibility (CWD), protein (N), and carbohydrate (C). In adults more than 4 years old we detected a significant seasonal cementum growth pattern in spring-summer, whereas the formation of rest lines took place mainly from October to February. All of our findings show a photoperiod control of cementum seasonal growth patterns, linked to the organism's annual growth cycle, whereas N and C probably do not influence seasonal deposition patterns. The deposition of the cementum begins to stop when the photoperiod begins to decrease, i.e. when the days begin to be shorter, which in the Mediterranean ecosystems of southern Spain takes place in the autumn and winter months. At this time, the amount of dry matter in food consumed increases, and voluntary food intake decreases. The amount of dietary protein and carbohydrate seems to influence the amount of cementum deposited each year, rather than the seasonal deposition pattern, at least in adults. No significant seasonal pattern was found for the younger fallow deer. Until this seasonal pattern is clarified, young specimens should be excluded from cementochronology applications, such as season-at-death estimations. Studies on the quantitative thickness of cementum increments should also be performed in order to confirm cementochronology as a useful tool for studying climatic variations and their biological impacts. [ABSTRACT FROM AUTHOR]