New fossil anhingids from the upper Acre River (Late Miocene of southwestern Amazon).

Four extant species of anhingids are found worldwide, all belonging to a single genus (Anhinga). However, the fossil record reveals a much greater diversity of this group in the past. The oldest known anhingids date back to the upper Oligocene period in Australia, but during the Miocene epoch in South America, they achieved their most remarkable diversity.

Extinction at the end-Cretaceous and the origin of modern Neotropical rainforests.

The end-Cretaceous event was catastrophic for terrestrial communities worldwide, yet its long-lasting effect on tropical forests remains largely unknown. We quantified plant extinction and ecological change in tropical forests resulting from the end-Cretaceous event using fossil pollen (>50,000 occurrences) and leaves (>6000 specimens) from localities in Colombia. Late Cretaceous (Maastrichtian) rainforests were characterized by an open canopy and diverse plant-insect interactions.

Improving the taxonomy of fossil pollen using convolutional neural networks and superresolution microscopy.

Taxonomic resolution is a major challenge in palynology, largely limiting the ecological and evolutionary interpretations possible with deep-time fossil pollen data. We present an approach for fossil pollen analysis that uses optical superresolution microscopy and machine learning to create a quantitative and higher throughput workflow for producing palynological identifications and hypotheses of biological affinity. We developed three convolutional neural network (CNN) classification models: maximum projection (MPM), multislice (MSM), and fused (FM).

Miocene flooding events of western Amazonia.

There is a considerable controversy about whether western Amazonia was ever covered by marine waters during the Miocene [23 to 5 Ma (million years ago)]. We investigated the possible occurrence of Miocene marine incursions in the Llanos and Amazonas/Solimões basins, using sedimentological and palynological data from two sediment cores taken in eastern Colombia and northwestern Brazil together with seismic information. We observed two distinct marine intervals in the Llanos Basin, an early Miocene that lasted ~0.