DEFINICIONES BASICAS DEL RELEVAMIENTO ANUAL DE ENTIDADES QUE REALIZAN ACTIVIDADES CIENTIFICAS Y TECNOLOGICAS

It can be observed from the previous paragraph that megafaunal extinction has been long debated along these years and each side has contributed with both theoretical ground and evidences.

Chapter 2: Antecedents

59 Nevertheless the debate continues (Lorenzen et al. 2011; Bartlett et al. 2016; Grund et al. 2012) adding complexities to this thematic. This has to do with several associated problems.

1. Most of the climate hypothesis defenders tried to analyze this problem only in archaeological grounds. No evidence or scarce evidence means that humans were not involved. Nevertheless hunting or scavenging megafaunal sites exists. However, for climate hypothesis defenders, this information is not enough to really probe human involvement with megafauna‟ species. As Haynes (2007) argued, the solution is not claiming for more sites, given that human “intentionality” cannot be really proven in them. Megamammals could have been scavenged, used from fossil context or just can be coincidentally associated. Thus having more human-megafauna sites will not finish the discussion. On the other side record is always biased, partial and its discovery depends not only in program research, but also in “luck” in detecting early sites, given the different problems that can affect them, as pointed by Surovell and Grund (2012). Record of smaller mammal predation exists, as there is megamammal record, probing that first American population had a wide range diet. Nevertheless, megafauna‟s extinction cannot be analyzed just in archaeological grounds. As Surovell et al. (2016) have indicated, this problem goes beyond archaeological record itself. In a broader way, different lines of evidence and ecological information must be taken into account in order to confront this problem. For example, chronology of First and Last dates of megamammals and human appearance is a tool used by different researchers, not only for the Americas, but worldwide. In general terms, they point to the astonishing coincidence between human arrival and extinction event. Also, ecological traits are important features that researchers have highlighted. Low reproduction rate, exposed communities, or naivety are shared characteristic of animals that extinguished. This fact differentiates Quaternary extinction in comparison with other extinction events, where wider taxa of orders were affected by climate change. Thus, climate hypothesis defenders, adjust their analysis to only one kind of evidence, not allowing to have a broad panoramic of the situation.

2. There is a problem of interpretation between both sides. Human hypothesis defenders argues that certainly first American peopling must have used a wide range of resources. Nevertheless they also consider that human impact in megamammals‟ communities was the most probable cause of extinction, given that climate change weakened these low-reproductive and naive groups. However climate hypothesis defenders continue pointing that “the other side” only consider specialization over megafauna to explain extinctions over human-based ground (Wroe et al. 2004; Boulanger and Lyman 2014; Meltzer 2015). Thus they deny the more general view of who consider human intentionality into a general climatically and ecologically background. In this sense the debate is blocked (Monjeau et al. 2016) and accusations crosses between both sides. At the same time climate hypothesis defender leaved humans almost out of play in the extinction process.

3. At last, the debates will continue since researchers have their own filters, on what to accept and not accept as good and bad evidence. Most of the sites, associations or marks are deny for different

Chapter 2: Antecedents

60 questions. This happens with defenders of both sides. Fiedel (2009:26) for example have question one well excavated and analyzed site as Monte Verde. He affirms that one site is just an “anomalous” case in the record. In this sense, he uses the same logic that climatic defender pose to accuse: low evidence is no evidence. By the way, different authors question the validity of North American and South American sites with megafauna association depending on the position they defend. Different causes are claimed to reject the evidences, among them: material can be associated just by coincidence, sites are not well excavated, the information is not properly published, the pictures have low quality or there is lack or poverty of information. There is a sense of “authority” (Fiedel and Haynes 2004) in what good evidence is, or what bad evidence is, what can be “scientifically” accepted or not. If several sites are rejected or criticized, does not mean that the problem is the filter and not in the evidence itself? It this is the sense, not all the evidence can be evaluated under the same type of rules. Paleontological and archaeological record is very variable, thus it is not easy to apply the same taphonomical reasoning to all the sites (Surovell and Waguespack 2009).

In this complex panorama, this work will not resolve this non stopping debate. An incredible amount of work is published year after year, from different researchers in order to understand the causes of extinctions. Innumerable reviews of published evidence can defend or not the different positions, according to the theoretical ground of the researcher. At a broad way level, after human entered in the Americas, both direct and indirect types of impact would have been produced in the environment. Consequently, as pointed in the first part of the chapter this work, focus will be put in understanding paleoecological relationship between humans and megamammals native communities. Although very much debated, the evidence is still scarce, and was used generally to evaluate causes behind extinctions. Museum‟s collection can contribute with new information. Integration of it, with other sites, and with ecological information can be useful to get deep into how human scavenging/hunting activities could have incorporated in this new environment.