Comments on: “An anthropogenic modification in an Eremotherium tooth from northeastern Brazil”

Abstract

Over150yearsago,PeterW.LundproposedthatlateQuaternaryextinct megafauna (henceforth just megafauna) and Homo sapienscoexisted in Brazil (Lund, 1844), but only recently his hypothesiswas supported by direct radiocarbon dating on megafauna bones(Neves and Pilo, 2003; Hubbe et al., 2007, 2009, 2011). These datesshowed that in some Brazilian regions, at least some speciessurvived until the beginning of the Holocene and became extinctafter the arrival of the first human groups. Besides the chronolog-ical evidence which indicates that humans and megafauna lived inthe same region at the same time, there are also claims that theymayhaveinteractedmoreactivelybasedonthefindingofsingle(orvery few) bones or bone fragments associated with human occu-pation levels, near archeological material, or showing marks thatsuggest their usage by humans. However, based on the meticulousrevision provided by Prous (2002) it is possible to rule out most ofthese cases due to theircontroversial nature. In fact, few of those, ifany, can be held as solid evidence of this close interaction (notconsidering scavengingon bones from a long ago deceased animal;Prous and Fogaca,1999).Recently Dantas et al. (in press) reported the finding of a singletooth fragment of the ground sloth Eremotherium in Sergipe State,northeastern Brazil that, according to the authors, presentsanthropogenic marks that favor the coexistence of this species andH. sapiens. However, in our opinion their work does not providesolid evidence of an interaction of this nature and, therefore, theaim of this comment is to discuss the validity of their finding asreliable evidence of megafauna (more specifically Eremotherium)and humans coexistence in Sergipe. The coexistence and notablythe close interaction between the former and the later may haveimportant implications to the understanding of the initial humanoccupation of South America, hence this kind of finding should notbe taken as granted, but rather should be analyzed with rigorouscriteria. In the following comments, we question the interpretationof the marks seen in the tooth as human-made cutmarks based on1)thenatureandlocationofthecutmarksand2)thearchaeologicalandpaleontologicalcontextof thefinding.Furthermore,wediscussreasons why the conclusions based on this finding could beseverely distorted.Dantas et al. (in press: 1) described the marks found on thereported tooth as an “effort to build a ‘triangular’ object”. Based onthe material, the location of the marks and the scant informationprovided (e.g., it is notclear if morebones fromEremotheriumwerefound, if there are more bones from other species with marks,whichother species were found), it is hardtoaccept that the marksobserved are the result of human intervention on the tooth. Themarks are described by Dantas et al. (in press: 1) as being humanbecause they have “parallel grooved striations, narrower anddeeper, which follow the curvature of the tooth along apical andlateral borders.” Unfortunately, these characteristics are unclear tous in the pictures presented by the authors. Fig. 2F shows onlystriations; Fig. 2G appear to show microwear striations, when thescaleofthephoto(0.1mm)istakenintoaccount;andFig.2Hshowsa network of shallow striations that crisscross the surface in everydirection. In summary, it is not possible to see the diagnosticfeatures in the pictures presented by the authors to justify theirconclusions of an anthropogenic origin for them.Added to the diagnostic difficulties of the marks in this tooth,their occurrence is not in accordance to the standard patternsobserved for food processing in ethnographic and archaeologicalcontexts (e.g., Walker, 1978; Lupo, 2002; Lyman, 2005; Martinez,2009), thus diminishing the possibility of butchering marks onthis tooth. Indeed, Dantas et al. (in press) never claimed thesemarks were the result of butchering, however it is very hard to