**5. Acknowledgement**

114 International Perspectives on Global Environmental Change

The Felidae HR-size structure is rather different from that of Canidae. There are four groups of HR-size clearly distinguished from Middle to Late Pleistocene (Figure 4). The smallest HR-sizes correspond to the latest Miocene and the latest Middle to Late Pleistocene. During the Late Pliocene, the intermediate HR-sizes overlap. This moment was characterized by the predominance of open and mixed habitats. In the present African landscape, most of the large predators are abundant in open savannas and savannas-woodlands, coincident with the highest ungulate densities. Rodriguez et al. (2004) showed an increase of size for the ungulates of that time, and without small-sized herbivores. This pattern remains a more close fit between prey and predator. New species appear during Lower Pleistocene and seem to begin a competitive displacement of the four groups of HR-size. After the "Wolf Event" (latest Early Pleistocene), the intermediate niche is segregated into two. This pattern suggests competitive size displacements as the main influence that might have caused HR-

The Hyaenidae pattern is similar to that of Canidae (Figure 4). The distribution of HR-size is conditioned by the diet, but this pattern was acquired previously and the presence of omnivorous species is occasional. The Hyaenidae were more diverse during the Late Miocene. Together with a precocious bone-eater hyaenidae, *Adcrocuta eximia*, two thalassictine forms were recorded. The "thalassictine group" is basically canid-like and establishes the general trend toward hypercarnivory (Werdelin & Solounias, 1991). All these taxa disappeared at the end of the Miocene and were replaced by a new hyaenid fauna. The canid-likehyaenids show a decrease in diversity that is strongly correlated with the arrival of Canidae into Eurasia during the Late Miocene-Early Pliocene. However, the only hunting hyaenid, *Chasmaportetes lunensis*, continues successfully during the Pliocene. Its disappearance in the Early Pleistocene seems to be related to the "Wolf Event". *C. lunensis* was the only cursorial, meat and bone eater hyaenid (Turner et al., 2008), adapted to open habitats. The Pliocene shows the full emergence of an organised guild of large carnivores in Europe. The appearance of *Pliocrocuta* at the R BU, followed by the gigantic *Pachycrocuta* at Late Pliocene-Early Pleistocene, shows that hyenas were able to obtain a consistent living from scavenging when necessary. In these taxa, the bone cracking component of the dentition is developed at the expense of the shearing component. Scavenging and hunting form part of a spectrum of behaviours. Living hyenas show a range of food-obtaining strategies that go through various aspects of their skeletal morphology (Wederlin & Solounias, 1991; Turner et al., 2008). The "Wolf Event" did not represent any important change despite the immigration of *Pachycrocuta brevirostri*s, the largest true hyena ever recorded. Only one species of hyaenid was recorded from this event to latest Pleistocene,

The analysis of Spanish Carnivora diversity trends shows that the hypothesis of a direct influence by climate change is partially supported by the data. There are two main moments of maximum diversity. The first one occurred during the late Pliocene, followed by a detached decrease during the Early Pleistocene. This lapse of time coincides with the progressive development of the Mediterranean double seasonality (related to the emergence of cold winters) that culminated with the start of the Pliocene glacial trend at 2.7-2.6 Ma (Suc et al., 1995; Suc & Popescu, 2005). The establishment of glacial cycles of 41 Ka is consistent with the diversity decrease during the Late Pliocene–Early Pleistocene. The second increase

size changes.

*Crocuta crocuta*.

**4. Remarks** 

Work supported by a Projects CGL2007-60790/BTE and CGL2010-19116/BOS from the Dirección General de Investigación Científica y Técnica of Spain and Projects AECID A/023681/09 and A/030111/10; grants from the Universidad Nacional del Centro de la provincial de Buenos Aires (http://www.unicen.edu.ar) and the Project ANPCYT (http://www.agencia.gov.ar) PICT 07-01563, Argentina. The funders had no role in study design, decision to publish, or preparation of the manuscript.
