Editorial Preface to Special Issue: Exploring the impact of Andean uplift and climate on life evolution and landscape modification: From Amazonia to Patagonia

Abstract

• Uplift of the Northern Andes (from Peru to Colombia) took place from Late Cretaceous to Paleocene (72 and 60 Ma), and was driven by collision of the South American plate with the Caribbean Arch. This process affected drainage directions and paleogeography shaping the present Andes configuration. • Studies in the Northern Andes concur with Late Cretaceous tectonism and suggest that uplift took place in three-stages. During the final Neogene uplift stage, the Antioquia plateau (Central Cordillera, Northern Andes) is thought to have achieved altitudes higher than present. • Subsurface processes, such as slab-flattening drove uplift in Central Cordillera (Northern Andes) and caused an asymmetric topography that affected drainages and biodiversity development. • Climate as a driver of mountain uplift remains contentious, but it is clear that uplift strongly affects climate and environment, due to the orographic rain shadow effect. • Multiple studies found that Andean uplift played a key role in shaping the evolutionary history and biodiversity patterns in both plants and animals, even in mutualistic species relationships. The effect of uplift on biogeographic history is not limited to the Andes mountains, but also extends into the Amazon drainage basin with soils in the western Amazonia being most species rich. During the Neogene, eastern Amazonia gradually became species-enriched through biotic interchange. • The effects of Andean uplift on biota add to other fundamental factors, such as climate, environment and dispersal, all of which contribute to the modern biodiversity patterns in South America and their evolutionary history. • The Neotropics were hot and humid during Eocene global warming. However, paleobotanical studies in the Northern Andes suggest that during towards the end of the Eocene a shift towards arid and seasonal climatic conditions occurred. In western Amazonia the EOT is further marked by a sea level drop, and a shift from deltaic to fluvial conditions that is accompanied by a decline in species richness. • In Patagonia the Oligocene ‘icehouse’ is characterized by a species poor assemblage. Towards the MCO there is an increase in species diversity with a subsequent decline in the MMCT. The biggest paleobotanical change, however, occurs in the late Miocene and is marked by the rise in arid taxa. This coincides with the uplift of the easternmost flank of the Andes and formation of a rain shadow. Aridification and sea level drop was initiated in the MMCT and culminated in the late Miocene. In the Northern Andes this transition is recognized by a dramatic change in paleosoil profiles. • Marine incursions and fluctuating sea level played an important part in Amazonia's history and evidence of this can be found in middle and late Miocene deposits in the western Amazon. Sediment records in the large Pebas wetland system (western Amazon) indicate that orbital forcing controlled sedimentation while the towering Central and Northern Andes provided the sediment supply. • Holocene records of Amazonia suggest rainforest trees are resilient to natural drying but not to fire and deforestation. A stark warning that human influence is more devastating than climate change.