![]() theses and dissertations) and published data (i.e. Here, we present the most comprehensive bibliographic review of fossil lissamphibians from South America to date, covering unpublished (e.g. This huge biodiversity is directly related to the complex geologic history of South America, which includes key events like the Gondwanan breakup, its isolation during parts of Mesozoic and Cenozoic, the Andean uplift, and the formation of the Panamá isthmus. Nowadays, lissamphibians are widely distributed in all continents, except Antarctica, but are particularly diversified in South America, where almost 3,000 species are found. We conclude that the obtained results do not support the Holocene survival of the megafauna in the Pampas.Īnurans, along with urodeles and caecilians are the extant representatives of the clade Lissamphibia. In sum, they caused the degradation of collagen and the subsequent contamination by fulvic acids from the overlaying soil, which classic pretreatment techniques could not remove. The previously obtained Early Holocene ages of megafauna bones resulted from the interrelation of various factors as physical and chemical weathering, humification processes linked to pedogenesis, and diagenetic processes. In this article, we apply different methodological procedures (chemical, geoarchaeological and taphonomic analysis) in order to reconstruct the formation at the Campo Laborde the site and identify the processes and agents that affected its chronology. However, new dates from the same sample, purified from humates with XAD-2 resin, gave results of ~10,650 14C years BP. ![]() The combination of these factors has produced suspicious results, leading to the proposition of the Holocene survival in the region of the extinct Pleistocene megamammals such as the Megatherium Holocene ages from the Campo Laborde site. Many bone samples do not have collagen or have poor preservation giving collagen of questionably quality, in many cases it is contaminated by humic substances. Pryor, Archaeological Review from Cambridge, Vol.Dating bone collagen has been problematic in the Argentinean Pampas. … a book designed for hardcore specialists focusing on the minutiae of extinction events specifically in the Americas …. … the book appears smartly presented, a slim hardback book that is well laid out, with clear black-and-white images scattered throughout the chapters. … discusses the extinction of genera across North and South America, with a single chapter focusing on the West Indies. ![]() “Addresses one of the most controversial issues of the last glacial period, which affected ecosystems around the world: American megafaunal extinctions. Provide the broadest (and, in many respects, the most helpful) perspective by considering North and South America in conjunction rather than in isolation. " Provides a very valuable overview of the current state of the extinction literature, referencing not just publications but also numerous conference presentations. #Tales of arise megafauna bone professionalAcademic and professional libraries, upper-division undergraduate and above." W. Eleven contributors present methodologically sound approaches that result in data-rich research. Haynes … thoroughly, fairly, and at times humorously frames the debate and puts the present studies in context. "This excellent volume is an antidote to the rhetorical bombast. ![]() Different chapters in this volume provide in-depth resumés of the chronology of the extinctions in North and South America, the possible insights into animal ecology provided by studies of stable isotopes and anatomical/physiological characteristics such as growth increments in mammoth and mastodont tusks, the clues from taphonomic research about large-mammal biology, the applications of dating methods to the extinctions debate, and archeological controversies concerning human hunting of large mammals. The last published volume with similar (but not identical) themes - Extinctions in Near Time- appeared in 1999 since then a great deal of innovative, exciting new research has been done but has not yet been compiled and summarized. The coupling of these extinctions with the earliest appearance of human beings has led to the suggestion that foraging humans are to blame, although major climatic shifts were also taking place in the Americas during some of the extinctions. Another equally mysterious wave of extinctions affected large Caribbean islands around 5,000 years ago. 13,000 calendar years ago in North America and about 1,000 years later in South America. ![]() The volume contains summaries of facts, theories, and unsolved problems pertaining to the unexplained extinction of dozens of genera of mostly large terrestrial mammals, which occurred ca. ![]()
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