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The Amazon hosts one of the largest and richest rainforests in the world, but its origins remain debated. Growing evidence suggests that geodiversity and geological history played essential roles in shaping the Amazonian flora. Here we summarize the geo-climatic history of the Amazon and review paleopalynological records and time-calibrated phylogenies to evaluate the response of plants to environmental change. The Neogene fossil record suggests major sequential changes in plant composition and an overall decline in diversity. Phylogenies of eight Amazonian plant clades paint a mixed picture, with the diversification of most groups best explained by constant speciation rates through time, while others indicate clade-specific increases or decreases correlated with climatic cooling or increasing Andean elevation. Overall, the Amazon forest seems to represent a museum of diversity with a high potential for biological diversification through time. To fully understand how the Amazon got its modern biodiversity, further multidisciplinary studies conducted within a multimillion-year perspective are needed. ▪ The history of the Amazon rainforest goes back to the beginning of the Cenozoic (66 Ma) and was driven by climate and geological forces. ▪ In the early Neogene (23–13.8 Ma), a large wetland developed with episodic estuarine conditions and vegetation ranging from mangroves to terra firme forest. ▪ In the late Neogene (13.8–2.6 Ma), the Amazon changed into a fluvial landscape with a less diverse and more open forest, although the details of this transition remain to be resolved. ▪ These geo-climatic changes have left imprints on the modern Amazonian diversity that can be recovered with dated phylogenetic trees. ▪ Amazonian plant groups show distinct responses to environmental changes, suggesting that Amazonia is both a refuge and a cradle of biodiversity.

The documentation of biodiversity distribution through species range identification is crucial for macroecology, biogeography, conservation, and restoration. However, for plants, species range maps remain scarce and often inaccurate. We present a novel approach to map species ranges at a global scale, integrating polygon mapping and species distribution modelling (SDM). We develop a polygon mapping algorithm by considering distances and nestedness of occurrences. We further apply an SDM approach considering multiple modelling algorithms, complexity levels, and pseudo-absence selections to map the species at a high spatial resolution and intersect it with the generated polygons. We use this approach to construct range maps for all 1957 species of Fagales and Pinales with data compilated from multiple sources. We construct high-resolution global species richness maps of these important plant clades, and document diversity hotspots for both clades in southern and south-western China, Central America, and Borneo. We validate the approach with two representative genera, Quercus and Pinus, using previously published coarser range maps, and find good agreement. By efficiently producing high-resolution range maps, our mapping approach offers a new tool in the field of macroecology for studying global species distribution patterns and supporting ongoing conservation efforts., Entomologia Experimentalis et Applicata, 170 (6), ISSN:0013-8703, ISSN:1570-7458

Plate reconstructions of the Panthalassa Ocean typically portray a simple system of diverging plates surrounded by active margins, yet geological and seismic tomographic records demonstrate that intra-oceanic subduction existed. Here, we reconstruct the plate tectonic evolution of the pre-Cretaceous intra-oceanic Oku-Niikappu island arc, remnants of which are exposed on Hokkaido, Japan. This arc formed at a Jurassic subduction zone separating two oceanic plates: the Izanagi Plate and the here proposed ‘Izanami’ Plate. The Oku-Niikappu arc was previously shown to have gone extinct in an intra-oceanic setting, was subsequently (hyper)extended, and overlain by Berriasian cherts. The extinct arc remained on the Panthalassa ocean floor for ∼45 Myr until its ∼100 Ma accretion to Hokkaido, revealing an original position far from the continental margin and likely above the previously identified Telkhinia slabs. We show that arc extinction coincided with a northwestern Panthalassa plate reorganization recorded by a ∼30° change in spreading direction, and that extinction and subsequent extension of the arc is straightforwardly explained by subduction of the Izanami-Pacific ridge followed by continued divergence between the Izanagi and Pacific plates. From our reconstruction, it follows that the outer zone of Japan, to which the accretionary complex in which the Oku-Niikappu Complex resides belongs, was separated from the inner zone by a back-arc basin during the Early to mid-Cretaceous. This study illustrates the value of accretionary orogens in the development of plate reconstructions of lost oceanic plates and ancient continental margins, particularly when combined with seismic tomographic and marine geophysical data sets., Tectonics, 40 (8)

The Panthalassa Ocean, which surrounded the late Paleozoic-early Mesozoic Pangea supercontinent, was underlain by multiple tectonic plates that have since been lost to subduction. In this study, we develop an approach to reconstruct plate motions of this subducted lithosphere utilizing paleomagnetic data from accreted Ocean Plate Stratigraphy (OPS). We first establish the boundaries of the Panthalassa domain by using available Indo-Atlantic plate reconstructions and restorations of complex plate boundary deformation at circum-Panthalassa trenches. We reconstruct the Pacific Plate and its conjugates, the Farallon, Phoenix, and Izanagi plates, back to 190 Ma using marine magnetic anomaly records of the modern Pacific. Then, we present new and review published paleomagnetic data from OPS exposed in the accretionary complexes of Cedros Island (Mexico), the Santa Elena Peninsula (Costa Rica), the North Island of New Zealand, and Japan. These data provide paleolatitudinal plate motion components of the Farallon, Phoenix and Izanagi plates, and constrain the trajectories of these plates from their spreading ridges towards the trenches in which they subducted. For 83 to 150 Ma, we use two independent mantle frames to connect the Panthalassa plate system to the Indo-Atlantic plate system and test the feasibility of this approach with the paleomagnetic data. For times prior to 150 Ma, and as far back as Permian time, we reconstruct relative and absolute Panthalassa plate motions such that divergence is maintained between the Izanagi, Farallon and Phoenix plates, convergence is maintained with Pangean continental margins in Japan, Mexico and New Zealand, and paleomagnetic constraints are met. The reconstruction approach developed here enables data-based reconstruction of oceanic plates and plate boundaries in the absence of marine magnetic anomaly data or mantle reference frames, using Ocean Plate Stratigraphy, paleo-magnetism, and constraints on the nature of circum-oceanic plate boundaries. Such an approach is a crucial next step towards quantitative reconstruction of the currently largely unknown tectonic evolution of the Earth's oceanic domains in deep geological time.

Intriguing latest Eocene land-faunal dispersals between South America and the Greater Antilles (northern Caribbean) has inspired the hypothesis of the GAARlandia (Greater Antilles Aves Ridge) land bridge. This landbridge, however, should have crossed the Caribbean oceanic plate, and the geological evolution of its rise and demise, or its geodynamic forcing, remain unknown. Here we present the results of a land-sea survey from the northeast Caribbean plate, combined with chronostratigraphic data, revealing a regional episode of mid to late Eocene, trench-normal, E-W shortening and crustal thickening by ∼25%. This shortening led to a regional late Eocene–early Oligocene hiatus in the sedimentary record revealing the location of an emerged land (the Greater Antilles-Northern Lesser Antilles, or GrANoLA, landmass), consistent with the GAARlandia hypothesis. Subsequent submergence is explained by combined trench-parallel extension and thermal relaxation following a shift of arc magmatism, expressed by a regional early Miocene transgression. We tentatively link the NE Caribbean intra-plate shortening to a well-known absolute and relative North American and Caribbean plate motion change, which may provide focus for the search of the remaining connection between ‘GrANoLA’ land and South America, through the Aves Ridge or Lesser Antilles island arc. Our study highlights the how regional geodynamic evolution may have driven paleogeographic change that is still reflected in current biology.

The Eocene (~50–45 Ma) major absolute plate motion change of the Pacific plate forming the Hawaii‐Emperor bend is thought to result from inception of Pacific plate subduction along one of its modern western trenches. Subduction is suggested to have started either spontaneously, or result from subduction of the Izanagi‐Pacific mid‐ocean ridge, or from subduction polarity reversal after collision of the Olyutorsky arc that was built on the Pacific plate with NE Asia. Here we provide a detailed plate‐kinematic reconstruction of back‐arc basins and accreted terranes in the northwest Pacific region, from Japan to the Bering Sea, since the Late Cretaceous. We present a new tectonic reconstruction of the intraoceanic Olyutorsky and Kronotsky arcs, which formed above two adjacent, oppositely dipping subduction zones at ~85 Ma within the north Pacific region, during another Pacific‐wide plate reorganization. We use our reconstruction to explain the formation of the submarine Shirshov and Bowers Ridges and show that if marine magnetic anomalies reported from the Aleutian Basin represent magnetic polarity reversals, its crust most likely formed in an ~85‐ to 60‐Ma back‐arc basin behind the Olyutorsky arc. The Olyutorsky arc was then separated from the Pacific plate by a spreading ridge, so that the ~55‐ to 50‐Ma subduction polarity reversal that followed upon Olyutorsky‐NE Asia collision initiated subduction of a plate that was not the Pacific. Hence, this polarity reversal may not be a straightforward driver of the Eocene Pacific plate motion change, whose causes remain enigmatic.

Global tectonic reconstructions of pre‐Cenozoic plate motions rely primarily on paleomagnetic and geological data from the continents, and uncertainties increase significantly with deepening geological time. In attempting to improve such deep‐time plate kinematic reconstructions, restoring lost oceanic plates through the use of geological and seismic tomographical evidence for past subduction is key. The North American Cordillera holds a record of subduction of oceanic plates that composed the northeastern Panthalassa Ocean, the large oceanic realm surrounding Pangea in Mesozoic times. Here we present new paleomagnetic data from subduction‐related rock assemblages of the Vizcaíno Peninsula of Baja California, Mexico, which yield a paleolatitudinal plate motion history equal to that of the North American continent since Late Triassic time. This indicates that the basement rocks of the Vizcaíno Peninsula formed in the forearc of the North American Plate, adjacent to long‐lived eastward dipping subduction at the southern part of the western North American continental margin. Tomographic images confirm long‐lived, uninterrupted eastward subduction. We correlate episodes of overriding plate shortening and extension to flat and steep segments of the imaged slab. By integrating paleomagnetic, geological, and tomographic evidence, we provide a first‐order model that reconciles absolute North American plate motion and the deformation history of Mexico since Late Triassic time with modern slab structure.

The North American Cordillera has been shaped by a long history of accretion of arcs and other buoyant crustal fragments to the western margin of the North American plate since early Mesozoic time. The southernmost accreted terrane is the Guerrero terrane of southwestern Mexico, a latest Jurassic-Cretaceous volcanic arc built on a Triassic accretionary prism. Interpretations of the origin of the Guerrero terrane vary: Some authors consider it a far-traveled, exotic intra-oceanic island arc, while others view it as the (par)autochthonous, extended North American continental margin. We present new paleomagnetic and U-Pb zircon data from Lower Cretaceous sedimentary rocks of the Guerrero terrane. These data show that the Guerrero terrane has a latitudinal plate-motion history equal to that of the North America plate, both before and after accretion. This confirms paleogeographic models in which the Guerrero arc successions formed on North American crust that rifted away from the Mexican mainland by approximately east-west opening of a back-arc basin above an eastward-dipping subduction zone. Additionally, it renders alternative paleogeographical models in which the Guerrero terrane is considered to be exotic to the North American continent unlikely. The phase of back-arc spreading resulted in the short-lived existence of an additional "Guerrero" tectonic plate between the North American and Farallon plates and, upon closure of the back-arc basin, the growth of the North American continent.