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Oriental plane tree (Platanus orientalis) is native to the East Mediterranean region and sister to three western North American species, together forming the Pacific North American–European (PNA‐E) clade. Its sister clade, comprising several eastern North American–Mexican species, has been termed the Atlantic North American (ANA) clade. The origins of P. orientalis and the western North American–western Eurasian disjunction in the PNA‐E clade are poorly understood, with the North Atlantic and Bering land bridges being possible corridors for trans‐continental migration. Molecular phylogenetic studies suggested ancient hybridization between the ANA and PNA‐E clades prior to differentiation of modern species' lineages. We traced ANA‐ and PNA‐E‐specific leaf traits in the fossil record to locate areas of possible ancient hybridization. Leaf traits characteristic of the PNA‐E clade occurred in western North America (late Eocene of Montana, Early Miocene of Alaska) prior to appearing in the European fossil record. Fossil‐species with mixed PNA‐E–ANA leaf traits occurred in the Oligocene of Central Asia and Eocene and Miocene of western North America. In contrast, eastern North America and the Atlantic region hosted fossil‐species with leaf traits characteristic of modern ANA clade members. We propose that precursors of Platanus orientalis migrated to Europe via Beringia and through Central Asia. Initially, these Eurasian ancestors possessed ancestral PNA‐E clade leaf morphologies, which were gradually replaced by P. orientalis‐specific traits. Treated as a single fossil‐species, we document the evolution of P. academiae from predominately three‐lobed leaves in Miocene strata to narrowly five‐lobed leaves resembling modern P. orientalis in younger deposits of Greece. [ABSTRACT FROM AUTHOR]

SUMMARY: Standard models of plant speciation assume strictly dichotomous genealogies in which a species, the ancestor, is replaced by two offspring species. The reality in wind‐pollinated trees with long evolutionary histories is more complex: species evolve from other species through isolation when genetic drift exceeds gene flow; lineage mixing can give rise to new species (hybrid taxa such as nothospecies and allopolyploids). The multi‐copy, potentially multi‐locus 5S rDNA is one of few gene regions conserving signal from dichotomous and reticulate evolutionary processes down to the level of intra‐genomic recombination. Therefore, it can provide unique insights into the dynamic speciation processes of lineages that diversified tens of millions of years ago. Here, we provide the first high‐throughput sequencing (HTS) of the 5S intergenic spacers (5S‐IGS) for a lineage of wind‐pollinated subtropical to temperate trees, the Fagus crenata – F. sylvatica s.l. lineage, and its distant relative F. japonica. The observed 4963 unique 5S‐IGS variants reflect a complex history of hybrid origins, lineage sorting, mixing via secondary gene flow, and intra‐genomic competition between two or more paralogous‐homoeologous 5S rDNA lineages. We show that modern species are genetic mosaics and represent a striking case of ongoing reticulate evolution during the past 55 million years. Significance Statement: The evolution of extra‐tropical wind‐pollinated tree genera involves dynamic speciation processes. High‐throughput sequencing of the multi‐copy, potentially multi‐locus 5S rDNA reveals a complex history of hybrid origins, lineage sorting and mixing, and intra‐genomic competition between paralogous‐homeologous loci in the core group of Eurasian beech trees (genus Fagus) and their distant relative, F. japonica. The modern species are genetic mosaics and represent a striking case of at least 55 million years of ongoing reticulate evolution. [ABSTRACT FROM AUTHOR]

The ecological impacts of consumption are well acknowledged, and most people worldwide are likely to have encountered proofs for or information about it. Likewise, online and offline media seem to be full of information on the issue. Even so, large numbers of people are 'non‐political' consumers, inconsiderate of the ethical and ecological implications of what they buy and consume. Using representative survey data from Sweden collected in 2019, this paper shows that a major reason for non‐political consumerism can be seen in the lack of interpersonal 'recruitment' efforts; that is, deliberate attempts by some to influence another's consumption. Moreover, the analyses show that for a person having faced such attempts by others to influence their consumption is distinct from them discussing political consumption issues. With this, the paper also provides one of the first large‐N studies confirming recent theoretical propositions of an extended definition of political consumerism: discussion, that is, discursive action, is a sub‐form of political consumerism next to boycotting, buycotting, and lifestyle change. Interpersonal influence, in turn, is a key predictor of political consumerism. Altogether, the results suggest that spreading information may feed discursive actions. Yet, to get more people change their consumption choices and engage in political consumerism, what is needed is that people influence each other to do so. [ABSTRACT FROM AUTHOR]

Late Oligocene leaf assemblages from four sites in Southwestern Siberia (Kurgan, Tyumen, Omsk oblasts) are described. Twenty-three leaf taxa and 3 reproductive structures represent local vegetation of a lake (Salvinia, Typha, Phragmites, Nelumbo, Hemitrapa, Liquidambar, Pterocarya, Alnus, Populus, Salix, Nyssa). Additionally, 57 spore and pollen taxa were recorded from one site (Shish River). Gymnosperms dominate the assemblage with ~30% Pinaceae and ~25% taxodiaceous (papillate) Cupressaceae pollen. Ferns and peat mosses (Sphagnaceae) comprised ~6%. Angiosperms were dominated by Fagaceae, Betulaceae, Juglandaceae and Ulmus and comprised a few exotic elements (Liquidambar, Eucommia, Nyssa, Symplocos); scarce herbaceous plants reflect lakeshore vegetation. The flora of the Turgay type comprised old elements (Nelumbo protospeciosa, Liquidambar europaea, taxodiaceous/papillate Cupressaceae, Quercus sect. Protobalanus) and taxa present in Siberia/Kazakhstan during the Paleogene with later arrivals in Europe (Ulmus pyramidalis, Quercus pseudocastanea, Alnus julianiformis, Byttneriophyllum tiliifolium). A few taxa were endemic in the late Oligocene of western Siberia (Trapa praeconocarpa, Platycrater iljinskajae sp. nov.). Combined macrofossil and palynological evidence places the Shish River site flora into the late Oligocene Zhuravka (Turtas) Formation. Floras of similar composition from western Eurasia are commonly middle Miocene or younger in age highlighting the dynamic spatiotemporal evolution of temperate Eurasian floras during the Cenozoic. [ABSTRACT FROM AUTHOR]

We describe a new species of Ampelopsideae (Vitaceae), Nekemias mucronata sp. nov., from the Rupelian of Cervera (Spain) and revise another fossil species, Ampelopsis hibschii, originally described from Germany. Comparison with extant Ampelopsideae suggests that the North American species Nekemias arborea is most similar to Nekemias mucronata while the East Mediterranean Ampelopsis orientalis is the closest living relative of A. hibschii. Our review of fossil data indicates that, during the Eocene, four species of Ampelopsideae occurred in Eurasia, that is, N. mucronata in the Czech Republic, A. hibschii in Kazakhstan, and two fossil species in the Far East (Ampelopsis cercidifolia and Ampelopsis protoheterophylla). In the Oligocene, a new species, Ampelopsis schischkinii, appeared in Kazakhstan; meanwhile, N. mucronata spread eastwards and southwards, and A. hibschii mainly grew in Central Europe. In the late Oligocene, N. mucronata became a relict in the Iberian Peninsula and Nekemias might have persisted in Western Eurasia until the latest Miocene (“Ampelopsis” abkhasica). The last occurrence of A. hibschii was in the Middle Miocene in Bulgaria, probably a refuge of humid temperate taxa, along with Ampelopsis aff. cordata. Carpological remains suggest that this lineage persisted in Europe at least until the Pleistocene. Our data confirm previous notions of the North Atlantic and Bering land bridges being important dispersal routes for Ampelopsideae. However, such dispersion probably occurred during the Paleogene rather than the Neogene, as previously suggested. A single species of Ampelopsideae, A. orientalis, has survived in Western Eurasia, which appears to have been linked to a biome shift. [ABSTRACT FROM AUTHOR]