Using carbon and oxygen isotope records from soil-forming carbonate nodules in the central Andes as a proxy for hydroclimate changes, combined with atmospheric circulation simulations, researchers report evidence of strengthened Hadley circulation in South America during the Late Miocene Cooling, approximately 5.4-7 million years ago, along with increased subtropical aridification, grassland expansion, and evolution of high-crowned teeth in mammals, suggesting the influence of global climate change on the transition to near-modern ecosystems.
Article #18-10721: "Ecological and hydroclimate responses to strengthening of the Hadley circulation in South America during the Late Miocene cooling," by Barbara Carrapa, Mark T. Clementz, and Ran Feng.
MEDIA CONTACT: Barbara Carrapa, University of Arizona, Tucson, AZ; tel: 520-621-6632; e-mail: bcarrapa@email.arizona.edu
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