Tooth loss, survival, and resource use in wild ring-tailed lemurs ( Lemur catta): implications for inferring conspecific care in fossil hominids

Abstract

The degree of antemortem tooth loss seen in wild nonhuman primates is central to the ongoing debate concerning conspecific care in fossil hominids (see Holden, 2003). Lebel and Trinkaus (2002) argued that the extreme (R81.8%) antemortem tooth loss seen in Aubesier 11, a partial hominid mandible from the middle Pleistocene (Lebel et al., 2001), exceeds that of known samples of living nonhuman primates. Their argument follows that, because of its severely impaired masticatory system, this individual would have required some form of social assistance to survive (Lebel et al., 2001; Lebel and Trinkaus, 2002). DeGusta (2002, 2003) refuted this, arguing that the degree of tooth loss in archaic humans does not exceed that of wild nonhuman primates. Of interest, both Lebel and Trinkaus (2002) and DeGusta (2003) cited data on dental health in the population of ring-tailed lemurs (Lemur catta) at Beza Mahafaly Special Reserve, Madagascar (Sauther et al., 2002) in their arguments. As noted by DeGusta (2003), Lebel and Trinkaus (2002) were incorrect in their characterization of the data presented by Sauther et al. (2002), arguing that “wild-trapped individuals with extensively worn teeth disappear shortly after observation” (Lebel and Trinkaus, 2002: 672). Rather, Sauther et al. (2002) reported the long-term survival (several years) of two ringtailed lemurs with pronounced dental impairment. However, the data on tooth loss and individual survival presented by Sauther et al. (2002) were descriptive, rather than quantitative, and illustrate the need for comprehensive data on dental health and tooth loss in wild nonhuman primates. When considering hominid paleobiology in a comparative context, the choice of an appropriate analogue is important. Lebel and Trinkaus (2002) argued that the most appropriate direct comparison for understanding hominid paleobiology and inferring conspecific care in middle Pleistocene hominids is other archaic human populations, as the social systems and technology associated with modern human groups limit their relevance. They also noted the significance of large-bodied, wild * Corresponding author. Tel.: +1-815-753-0744; fax: +1-815-753-7027 E-mail addresses: fcuozzo@niu.edu (F.P. Cuozzo), sauther@stripe.colorado.edu (M.L. Sauther). Journal of Human Evolution 46 (2004) 623–631