Effects of climatic oscillations on the faunas. The Holocene Thermal Maximum and the displacement of armadillos in Argentina: Anatomical features and conservation

Abstract

The Dasypodidae (commonly known as armadillos) are exclusively from the Americas and have a long evolutionary history on the continents. They were frequently consumed by hunter-gatherers in the past and they are consumed by native people in the modern age along their distributional area. Both paleontological and archaeological records show that they inhabited areas in which they do not inhabit in the present-day. The study conducted on faunal remains at the Alfar site (southeast Buenos Aires Province, Argentina) allowed the determination of two different species (Zaedyus pichiy and Tolypeutes matacus) based on the ornamentation of the osteoderms that compose the animal´s carapace. Radiocarbon dating of Unit II (fossil bearing level, 5700 yBP) locates the human exploitation during a warm and arid climate period known as the Holocene Thermal Maximum. The armadillos found at Alfar site are absent in the area nowadays. Instead, they are distributed in arid/semiarid environments of the Patagonia and Central regions of Argentina, where the association is characteristic of the Monte ecoregion, 1000 km northwest far from Alfar site. The results here presented serve to support the hypothesis of the Dasypodidae as paleoenvironmental proxies and also to confirm the importance of paleozoology studies to apply in conservation biology.