3.5. Sexual dimorphism in dental wear
Differences in dental wear prevalence among males and females were assessed only for the Guiana dolphin S. guianensis and bottlenose dolphin Tursiops truncatus. Other species had few individuals of known sex.
In the Guiana dolphin, frequencies of wear were statistically similar among males and females (t = 0.3597; p = 0.7196). Males presented an average wear prevalence of 77% of their teeth (SD = ±31), and females of 75% (SD = ±33). On the other hand, wear frequencies were statistically different in males and females of the bottlenose dolphin (t = 3.1659; p = 0.0029). For this species, females had an average of 90% of their teeth worn (SD = ±13), while for males the average was 63% (SD = ±35) ( Fig. 7).