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Fossil pollen believed to be related to extant Hagenia abyssinica were discovered in the early Miocene (21.73 Ma) Mush Valley paleoflora, Ethiopia, Africa. Both the fossil and extant pollen grains of H. abyssinica were examined with combined light microscopy, scanning electron microscopy, and transmission electron microscopy to compare the pollen and establish their relationships. Based on this, the fossil pollen grains were attributed to Hagenia. The presence of Hagenia in the fossil assemblage raises the questions if its habitat has changed over time, and if the plants are/were wind pollinated. To shed light on these questions, the morphology of extant anthers was also studied, revealing specialized hairs inside the anthers, believed to aid in insect pollination. Pollen and anther morphology are discussed in relation to the age and origin of the genus within a molecular dated phylogenetic framework, the establishment of complex topography in East Africa, other evidence regarding pollination modes, and the palynological record. The evidence presented herein, and compiled from the literature, suggests that Hagenia was an insect‐pollinated lowland rainforest element during the early Miocene of the Mush Valley. The current Afromontane habitat and ambophilous (insect and wind) pollination must have evolved in post‐mid‐Miocene times.

Dental microwear analysis is a proxy for analysing the diet in extinct and extant vertebrates, especially mammals. The limits of these approaches are still rather poorly known, especially in terms of taphonomic impacts. Indeed, several physical or chemical phenomena may have altered the microscopic features linked to the diet and compromised their study. In this article, we evaluate the effect of sediment abrasion on teeth on low-magnification tooth wear studies. We used a tumbling machine in order to reproduce abrasion marks on 57 molars and premolars of Equus sp., Capra hircus and Sus scrofa employing two types of sediments: a mixture of clay and sand sediment with small (150-200 mu m) and rounded particles and a sandy one with larger (350-500 mu m) and sub-angular particles. The teeth underwent up to 2 h of tumbling simulation, and casts were made at regular intervals in order to evaluate the evolution of the taphonomic impact over time. Our experiment shows that (1) both sediments strongly alter the teeth after a certain time; (2) the fine particles contained in the mix of sand and clay sediment have a much stronger impact on the enamel than the sand; (3) the mix of clay and sand sediment tends to increase the number of pits and reduce the number of scratches, vice versa for the sand; and (4) sedimentary and dietary marks do not have the same morphology and can be distinguished. The abrasion marks (compared to dietary scratches) tend to be wider, shorter, with an isotropic distribution, more frequent on the most exposed parts of the teeth (such as the cusps or the edges). The pits resulting from sediment tumbling present an irregular morphology in comparison with dietary pits, which are rounder. Both sediments have an impact on the enamel surfaces. Thus, when signs

The pantropical Picrodendraceae produce mostly spheroidal to slightly oblate, echinate pollen grains equipped with narrow circular to elliptic pori that can be hard to identify to family level in both extant and fossil material using light microscopy only. Fossil pollen of the family have been described from the Paleogene of America, Antarctica, Australia, New Zealand, and Europe, but until now none have been reported from Afro-India. Extant pollen described here include representatives from all recent Picrodendraceae genera naturally occurring in Africa and/or Madagascar and south India and selected closely related tropical American taxa. Our analyses, using combined light microscopy and scanning electron microscopy, show that pollen of the Afro-Indian genera encompass three morphological types: Type 1, comprising only Hyaenanche; Type 2, including Aristogeitonia, Mischodon, Oldfieldia and Voatamalo; Type 3, comprising the remaining two genera, Androstachys and Stachyandra. Based on the pollen morphology presented here it is evident that some previous light microscopic accounts of spherical and echinate fossil pollen affiliated with Arecaceae, Asteraceae, Malvaceae, and Myristicaceae from the African continent could belong to Picrodendraceae. The pollen morphology of Picrodendraceae, fossil pollen records, a dated intra-familial phylogeny, seed dispersal modes, and the regional Late Cretaceous to early Cenozoic paleogeography, together suggest the family originated in the Americas and dispersed from southern America across Antarctica and into Australasia. A second dispersal route is believed to have occurred from the Americas into continental Africa via the North Atlantic Land Bridge and Europe.