Late Quaternary environmental and climatic history of the southern Chilean Lake Region interpreted from coleopteran (beetle) assemblages

• Main Author: Hoganson, John W.
• Format: Text
• Language: unknown
• Published: UND Scholarly Commons 1985
• Subjects: Paleoclimatology > Chile; Geology > Chile; Beetles; Fossil; Geology; Tundra
• Online Access: https://commons.und.edu/theses/141; https://commons.und.edu/context/theses/article/1140/viewcontent/Hoganson__John_W.__PhD_Diss._1985.pdf; https://commons.und.edu/context/theses/article/1140/filename/0/type/additional/viewcontent/Hoganson_Plates.zip

A diverse Coleoptera fauna of 462 species in 48 families was collected from 41 locations in the Parque Nacional de Puyehue and adjacent parts of the Lake Region of southern Chile. The sample locations ranged from rain forest habitats at sea-level to Andean tundra habitats at 1500 m msl. Cluster analysis of a Dice similarity coefficient matrix revealed a broad pattern of bioassociations within the large data base, Boundaries between the bioassociations correspond largely with those of the major vegetation zones implying that the distribution of the fauna is strongly influenced by the distribution of plants. Evidence from fossils indicates that the lowland beetle fauna during the interval 26,000 to 15,500 yr B,P. had a low diversity and was dominated by species of open-ground habitats. Forest species appeared in the lowlands between 15,000 and 14,000 yr B,P., at about the time of the last deglaciation. A fauna with similar characteristics to that of the Valdivian Rain Forest was not in place until about 13,000 yr B.P. No evidence was found to support claims made from palynological studies for a pronounced episode of colder and wetter climatic conditions in the interval from about 11,000 to 9,500 yr B.P. The patterns observed in the fauna began to develop about 13,000 yr B.P. and continued to do so until the present without any significant disruptions.