We provide a synopsis of similar to 60 million years of life history in Neotropical lowlands, based on a comprehensive survey of the Cenozoic deposits along the Quebrada Cachiyacu near Contamana in Peruvian Amazonia. The 34 fossil bearing localities identified have yielded a diversity of fossil remains, including vertebrates, mollusks, arthropods, plant fossils, and microorganisms, ranging from the early Paleocene to the late Miocene-?Pliocene (>20 successive levels). This Cenozoic series includes the base of the Huchpayacu Formation (Fm.; early Paleocene; lacustrine/fluvial environments; charophyte-dominated assemblage), the Pozo Fm. (middle + ?late Eocene; marine then freshwater environments; most diversified biomes), and complete sections for the Chambira Fm. (late Oligocene-late early Miocene; freshwater environments; vertebrate-dominated faunas), the Pebas Fm. (late early to early late Miocene; freshwater environments with an increasing marine influence; excellent fossil record), and Ipururo Fm. (late Miocene-?Pliocene; fully fluvial environments; virtually no fossils preserved). At least 485 fossil species are recognized in the Contamana area (similar to 250 'plants', similar to 212 animals, and 23 foraminifera). Based on taxonomic lists from each stratigraphic interval, high-level taxonomic diversity remained fairly constant throughout the middle Eocene-Miocene interval (8-12 classes), ordinal diversity fluctuated to a greater degree, and family/species diversity generally declined, with a drastic drop in the early Miocene. The Paleocene-?Pliocene fossil assemblages from Contamana attest at least to four biogeographic histories inherited from (i) Mesozoic Gondwanan times, (ii) the Panamerican realm prior to (iii) the time of South America's Cenozoic "splendid isolation", and (iv) Neotropical ecosystems in the Americas. No direct evidence of any North American terrestrial immigrant has yet been recognized in the Miocene record at Contamana. (C) 2015 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved

International audienceThe subduction of an aseismic ridge has important consequences on the dynamics of the overriding upper plate. In the central Andes, the Nazca Ridge subduction imprint can be tracked on the eastern side of the Andes. The Fitzcarrald arch is the long-wavelength topography response of the Nazca Ridge flat subduction, 750 km inboard of the trench. This uplift is responsible for the atypical three-dimensional shape of the Amazonian forelland basin. The Fitzearrald arch uplift is no older than Pliocene as constrained by the study of Neogene sediments and geomorphic markers, according to the kinematics of the Nazca Ridge subduction

Feather of the Penguin: Penguins are highly adapted for their cold, aquatic environment. Changes in their wings and feathers have allowed rapid swimming and protection from the near-freezing water. Clarke et al. (p. 954 , published online 30 September; see the cover) describe an early penguin, dating to about 35 million years ago, that includes well-preserved feathers. The melanosomes in the feathers, which influence their strength, as well as their color, are like those of many other aquatic birds and unlike those of present-day penguins, even though the morphology of the wings and feathers had already been modified. Thus, in penguins, the shape and form of the feather evolved before microstructural changes occurred. The melanosome arrangement also suggests that the penguin was mostly gray-brown.

Amazonia contains one of the world's richest biotas, but origins of this diversity remain obscure. Onset of the Amazon River drainage at approximately 10.5 Ma represented a major shift in Neotropical ecosystems, and proto-Amazonian biotas just prior to this pivotal episode are integral to understanding origins of Amazonian biodiversity, yet vertebrate fossil evidence is extraordinarily rare. Two new species-rich bonebeds from late Middle Miocene proto-Amazonian deposits of northeastern Peru document the same hyperdiverse assemblage of seven co-occurring crocodylian species. Besides the large-bodied Purussaurus and Mourasuchus , all other crocodylians are new taxa, including a stem caiman— Gnatusuchus pebasensis —bearing a massive shovel-shaped mandible, procumbent anterior and globular posterior teeth, and a mammal-like diastema. This unusual species is an extreme exemplar of a radiation of small caimans with crushing dentitions recording peculiar feeding strategies correlated with a peak in proto-Amazonian molluscan diversity and abundance. These faunas evolved within dysoxic marshes and swamps of the long-lived Pebas Mega-Wetland System and declined with inception of the transcontinental Amazon drainage, favouring diversification of longirostrine crocodylians and more modern generalist-feeding caimans. The rise and demise of distinctive, highly productive aquatic ecosystems substantially influenced evolution of Amazonian biodiversity hotspots of crocodylians and other organisms throughout the Neogene.