Highlights • Grasses have been a common component of the Amazon drainage basin (ADB) since at least the Neogene (23 Ma). • A large wetland, that accommodated extensive amounts of grass remains, existed in western Amazonia from around 23 to 9 Ma. • From c. 9 Ma, grasses were likely the successful pioneers of new habitats that formed on the Andean slopes, megafans, and the floodplains of the Amazon River. • The rising Andes, together with environmental and climate change, favoured grass development in the ADB during the Neogene and Quaternary. • In the last 5 million years, open surfaces in the high Andes offered comprehensive habitats for grass colonisation.

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<p>The Poaceae (the grass family) includes over 11000 species and covers large part of the Earth land surfaces. Their history is rooted in the Cretaceous, but this group only expanded fully over the globe during the late Miocene. In the Amazon drainage basin (ADB) grasses were at the core of a heated debate, in which it was hypothesized that during the Pleistocene glacial periods grasses replaced vast extents of the Amazon rainforest. Although this hypothesis is now rejected, the history of grasses in the ADB still remains to be resolved. In this paper we propose a 3-staged model for grass development in the ADB: (1) from c. 23 to 9 Ma western Amazonia was dominated by a megawetland (the ‘Pebas system’) that harboured large amounts of (aquatic?) grasses; (2) from c. 9 Ma Andean uplift prompted megafan and fluvial environments on the Andean slopes and in the Amazon lowlands respectively, these environments created new settings for grass colonization; (3) from c. 5 Ma grasses were firmly established in the tropical alpine vegetation (páramo), the tropical lowland floodplains (várzeas), and savannas (cerrado). To test these scenarios we analysed Neogene and extant Andes-Amazonian grasses by means of Fourier Transform Infrared spectroscopy, we performed a Light- and Scanning Electron Microscopy analysis, and compared the results with existing biomarker data from the Neogene sediments. Here we report on the preliminary results that, among others, suggest that in the middle Miocene aquatic (C3) taxa were comon in the Amazon lowlands. Although further study will have to confirm the precise nature of the ADB grass history, we anticipate that abiotic processes during the Neogene and Quaternary left a strong imprint in the grass phytogeography of northern South America.</p> <p> </p>

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Despite recent research, a systematic approach to understanding wildfire governance is lacking. This article addresses this deficit by systematically reviewing governance theories and concepts applied so far in the academic literature on wildfires as a step toward achieving their more effective and holistic management. We engage our findings with the wider governance literature to unlock new thinking on wildfires as a process and outcome. This comparative approach enables us to propose a novel framework for analyzing wildfire governance based on four pillars: (1) actor participation in decision-making and decision taking; (2) actor collaboration and coproduction across and within levels, scales, and networks; (3) path dependencies and local place-based dynamics of wildfire incidence and comprehension; and (4) actor adaptation to and anticipation of wildfire risk to fashion effective institutions that address the global wildfire challenge. We show how this framework can help specify a suite of bespoke analytical and policy practitioner approaches to facilitate preemptive and restorative wildfire strategies via new networks between communities, states, and wider society, thus providing the basis for more equitable and sustainable governance of wildfire risks and impacts.