In the laboratory, the length of the mandible (ML, ± 1 mm) was measured as a proxy of skeletal size (i.e. from the mesial border of the first incisor socket to the vertical part of the ramus, after having removed the flesh in these two points).
To estimate the age and tooth wear, mandibles were sectioned through a frontal plane between the entoconid-hypoconid and metaconid-protoconid of the first molar (M1) using a circular diamond saw [26 ]. The age (in years) was estimated by counting the milky-coloured cement layers on the root pad of the sectioned mesial section of M1, aided by a reflected light microscope at magnification x20 to x25 [27 ,28 ]. When M1 was missing, or the cement layers poorly differentiated, M2 was used and the age in years was estimated as the number of cement layers plus one.
Tooth wear was estimated by measuring, with the aid of a calliper and a magnifying glass, the thickness of the dentine on the sectioned mesial section of M1 (molar height, MH, ± 0.1 mm) from the top of the cementum of the radicular pad to the middle point of the sectioned crown [7 ,26 ]. It has been noted that although crown formation in M1 is fully complete at the age of 4 months [19 ,29 ], the completion of eruption and final positioning of the molar in the mandible does not take place until 3 years of age in red deer [19 ,20 (link)], and teeth also move in the mandible at very old age. Consequently, measuring molar height perpendicular from the mandible bone, labial or buccal, is not a reliable measurement of molar wear, especially in young age classes; by contrast, our MH measurement is independent of any movement of the molar in the mandible. We also measured crown size of the first permanent incisor (incisor height, IH, ± 0.1 mm), from the labial gingival sulcus to the median sagittal plane top of the crown [1 ].
Tooth wear was assessed as the negative relationship of crown height with age [7 ,26 ].
To estimate the age and tooth wear, mandibles were sectioned through a frontal plane between the entoconid-hypoconid and metaconid-protoconid of the first molar (M1) using a circular diamond saw [26 ]. The age (in years) was estimated by counting the milky-coloured cement layers on the root pad of the sectioned mesial section of M1, aided by a reflected light microscope at magnification x20 to x25 [27 ,28 ]. When M1 was missing, or the cement layers poorly differentiated, M2 was used and the age in years was estimated as the number of cement layers plus one.
Tooth wear was estimated by measuring, with the aid of a calliper and a magnifying glass, the thickness of the dentine on the sectioned mesial section of M1 (molar height, MH, ± 0.1 mm) from the top of the cementum of the radicular pad to the middle point of the sectioned crown [7 ,26 ]. It has been noted that although crown formation in M1 is fully complete at the age of 4 months [19 ,29 ], the completion of eruption and final positioning of the molar in the mandible does not take place until 3 years of age in red deer [19 ,20 (link)], and teeth also move in the mandible at very old age. Consequently, measuring molar height perpendicular from the mandible bone, labial or buccal, is not a reliable measurement of molar wear, especially in young age classes; by contrast, our MH measurement is independent of any movement of the molar in the mandible. We also measured crown size of the first permanent incisor (incisor height, IH, ± 0.1 mm), from the labial gingival sulcus to the median sagittal plane top of the crown [1 ].
Tooth wear was assessed as the negative relationship of crown height with age [7 ,26 ].
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