Middle and Late Holocene micromammal pathologies from Cueva Tixi (Tandilia range, Buenos Aires province, Argentina)

QUINTANA, CARLOS; ARANDA, CLAUDIA; LUNA, LEANDRO

Arica

Congreso; Middle and Late Holocene micromammal pathologies from Cueva Tixi (Tandilia range, Buenos Aires province, Argentina).; 2017

Universidad de Tarapacá

Samples of small mammal bones have not usually been studied from a paleopathological perspective. Different types of osseous lesions of mammals under 0.2 kg recovered from Cueva Tixi archaeological and paleontological site (Tandilia range, province of Buenos Aires, Argentina), are described and discussed. The microvertebrate sample includes 72,116 skeletal remains that belong to different taxa, which have a chronological range from the Late Pleistocene to the final Late Holocene: didelphids marsupials, rodents,bats, frogs, birds, snakes and fishes. Among mammals, rodents are the most abundant (NISP: 66,789), followed by didelphids marsupials (NISP: 339). Only 17 bones of rodents were pathologically affected. Differential diagnosis was conducted in each case, considering the limits of isolated bone analysis. Several types of traumatic events, entheseal changes, degenerative jointdiseases, probable cases of osteomyelitis and other pathologies, were identified. A highly demanding use of the musculoskeletal system is inferred. All the lesions identified were chronic, which means the animals were able tosurvive during the period of convalescence. In consequence, their adequate behavior allowed them to obtain food and defend themselves from predators, although in several cases (i.e., fractures) the decrease in locomotor capacitymay have been important. As the cause of death of all these specimens was depredation by the barn owl (Tyto alba), this limitation must have produced a lower escape potential. All the pathological bones correspond to rodentsbecause the barn owl consumes mainly these small mammals, while the recurrenceof diseases on bones of R. auritus is related to its great preponderance in the fossil record of Cueva Tixi. These pathological findings open new research avenues for this particular kind of animals, usually not considered inpaleopathological studies.