Climatic Changes and Orogeneses in the Late Miocene of Eurasia: The Main Triggers of an Expansion at a Continental Scale?

Migrations from the Qinghai-Tibetan Plateau (QTP) to other temperate regions represent one of the main biogeographical patterns for the Northern Hemisphere. However, the ages and routes of these migrations are largely not known. We aimed to reconstruct a well-resolved and dated phylogeny of Hippophae L. (Elaeagnaceae) and test hypothesis of a westward migration of this plant out of the QTP across Eurasian mountains in the Miocene. We produced two data matrices of five chloroplast DNA (cpDNA) and five nuclear DNA markers for all distinct taxa of Hippophae. These matrices were used to reconstruct phylogenetic relationships in the genus. In dating analyses, we first estimated the stem node age of Elaeagnaceae using five fossil records evenly distributed across a tree of Rosales. We used this estimate and two fossil records to calibrate the cpDNA and nDNA phylogenies of Hippophae. The same phylogenies were used to reconstruct ancestral areas within the genus. The monophyly of Hippophae, all five species, and most of subspecies was strongly supported by both plastid and nuclear data sets. Diversification of Hippophae likely started in central Himalayas/southern Tibet in the early Miocene and all extant distinct species had probably originated by the middle Miocene. Diversification of Hippophae rhamnoides likely started in the late Miocene east of the QTP from where this species rapidly expanded to central and western Eurasia. Our findings highlight the impact of different stages in uplift of the QTP and Eurasian mountains and climatic changes in the Neogene on diversification and range shifts in the highland flora on the continent. The results provide support to the idea of an immigration route for some European highland plants from their ancestral areas on the QTP across central and western mountain ranges of Eurasia in the late Miocene

Andean orogeny and the diversification of lowland neotropical rain forest trees:A case study in Sapotaceae

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordUnderstanding how species diversify and evolve in species-rich areas like the lowland rain forest in the Neotropics is critical for conservation in times of unprecedented threats. To determine how the Andean uplift, the formation of the Panama land bridge, and Pleistocene climatic fluctuations affected dispersal and diversification in the Sapotaceae subfamily Chrysophylloideae, we collected 146 Chrysophylloideae accessions in previously under-explored areas, generating one of the most geographically complete data sets for neotropical Sapotaceae. Sapotaceae is a good model to test diversification hypotheses in lowland neotropical rain forests as it predominantly occurs <1000 m altitude, and it is an abundant and species-rich group in this biome. We generated a time calibrated phylogeny of 123 Sapotaceae species based upon the nuclear ribosomal internal transcribed spacer region that suggests migration between lineages to the east and the west Andean Cordilleras occurred before and after periods of major uplift, indicating that the Andes did not represent a significant barrier to dispersal for Sapotaceae, although it may have promoted vicariance in some cases. Dispersal between South and Central America occurred mainly prior to the formation of the Panama land bridge, suggesting that this event did not affect migration patterns in Chrysophylloideae. We inferred diversification rates and detected three shifts in the phylogeny, but they are not congruent with tectonic movements during the middle Miocene and climatic changes during the Pleistocene. Finally, some species with restricted distributions appear to be phylogenetically nested within species with broader ranges, suggesting ancestor descendent relationships and insights into patterns of speciation in rain forest trees.Natural Environment Research Council (NERC)National Science Foundation (NSF)Geological Society of Americ

Assessment of genetic diversity using RAPD analysis in a germplasm collection of sea buckthorn

RAPD (Random amplified polymorphic DNA)-markkerien avulla kuvailtiin osaa tyrnin geenipankista, joka oli koottu jalostustarkoituksiin. Molekyylimarkkereita monistettiin 55 näytteestä, jotka edustivat viittä tyrnin (Hippophae rhamnoides L.) alalajia ja eri alalajien välisiä hybridejä. Kuudenkymmenenkolmen markkerin avulla laskettiin Dicen samankaltaisuus-kerroinmatriisi (Dice's similarity coefficient matrix) yksittäisten RAPD profiilien parittaisista vertailuista. Matriisiin perustuvien analyysien (UPGMA- and principal co-ordinate analyses) avulla kasvit jakautuivat ryhmiin, jotka vastaavat niiden taksonomista luokkaa ja maantieteellistä alkuperää. AMOVA-analyysi (analysis of molecular variance) todettiin käyttökelpoiseksi menetelmäksi arvioitaessa näytteiden taksonomisten ja maantieteellisten ryhmien välisiä ja sisäisiä geneettisen muuntelun osatekijöitä. Vaikka molemmista aineiston ryhmittelyvaihtoehdoista (taksonominen ja maantieteellinen alkuperä) paljastui ryhmien välistä muuntelua, pääosa molekyylivarianssista (arviolta 75 %) luettiin yhä ryhmien sisäisen muuntelun aiheuttamaksi. Yhteenvetona toteamme, että RAPD analyysi on käyttökelpoinen menetelmä tyrninäytteiden taksonomisen ja maantieteellisen alkuperän selvittämiseen.Random amplified polymorphic DNA (RAPD) markers were used to characterize a part of a sea buckthorn gene bank collected for plant breeding purposes. Molecular markers were generated in 55 cultivars and accessions, representing five subspecies of Hippophae rhamnoides L. and intraspecific hybrids between different subspecies. Sixty-three markers were used to generate a Dice's similarity coefficient matrix of pairwise comparisons between individual RAPD profiles. Cluster (UPGMA) and principal co-ordinate analyses, based on this matrix, revealed clustering of plants into groups which generally correspond to their taxonomic classification or geographic origin. The analysis of molecular variance (AMOVA) was found useful for estimating components of genetic variation between and within taxonomic and geographic groups of accessions and cultivars. Whereas both alternatives for grouping the material (taxonomic or geographic origin) resulted in significant between-group variation, the major part of molecular variance (approximately 75%) was still attributed to variation within groups. We conclude that the RAPD analysis is useful for clarification of taxonomic and geographic origin of accessions and cultivars of sea buckthorn.vokTyrnin geneettisen monimuotoisuuden arviointi RAPD analyysill

Multi-gene phylogeny of the pantropical subfamily Chrysophylloideae (Sapotaceae): evidence of generic polyphyly and extensive morphological homoplasy.

International audienceWe present a molecular phylogeny of 26 out of the 28 currently accepted genera in the subfamily Chrysophylloideae (Sapotaceae)using parsimony, parsimony jackknifing, and Bayesian inference. A data matrix of 8984 characters was obtained from DNA sequences of seven chloroplast loci, two nuclear loci, indels coded as binary characters, and morphology. Our phylogenetic reconstruction suggests that Chrysophyllum, Pouteria, and Pradosia, as well as some sections within Chrysophyllum and Pouteria, are all polyphyletic. These taxa were previously described largely on the basis of unique combinations of states for a set of morphological characters. Mapping some of these characters onto one of the most parsimonious trees indicates that the symplesiomorphic flower in the subfamily was probably 5-merous, had stamens inserted in the tube orifice, staminodes, seeds with foliaceous cotyledons, exserted radicle, and endosperm. These characters have subsequently been lost multiple times and cannot be used as synapomorphies to support broad generic concepts. Despite the high degree of homoplasy some well-defined clades can be described on the basis of alternative character state combinations. Also, many of these well-supported clades appear to be restricted to particular geographical areas (e.g. all taxa in Australasia form a monophyletic group). Hence, we suggest that the segregate genera Aningeria, Malacantha, and Martiusella may ultimately be resurrected, and probably also Donella and Gambeya, but their circumscriptions are still unclear. One species, Chrysophyllum cuneifolium, may have originated from a hybridization event between continents where the maternal genome (cpDNA) comes from South America and the nuclear genome comes from Africa

Effects of population size on genetic diversity, fitness and pollinator community composition in fragmented populations of Anthericum liliago L

International audienceThe genetic and fitness consequences of habitat fragmentation on the dry grassland species Anthericum liliago L. (Anthericaceae) were examined. We used random amplified polymorphic DNA (RAPD) markers to determine the distribution of genetic diversity within and among 10 German A. liliago populations, ranging in size from 116 to over 2 million ramets. The genetic diversity of an A. liliago population was highly positively correlated with its population size. The overall differentiation among populations (Phi-ST = 0.41, P\0.0001, AMOVA) was considerably higher than expected for a species with a mixed breeding system. No strong correlation (P\0.01) was detected between fitness parameters and population size and genetic diversity. The reproductive output (seeds per ramet) was only highly correlated (P\0.001) with the proportion of flowering ramets in a population which could be caused by a more effective pollination in large populations which are more attractive to specialized pollinators. The specialized A. liliago pollinator Merodon rufus (Syrphidae) and high abundances of solitary bees could only be found in A. liliago populations with more than 10,000 individuals. Genetic differentiation among the investigated A. liliago populations may have been caused by limited seed and pollen dispersal and a mixed mating system permitting a high selfing rate. The differentiation among the small and isolated populations lacking main pollinators seems to be caused by genetic drift

Fewer chromosomes, more co-occurring species within plant lineages - a likely effect of local survival and colonization

International audiencePREMISE: Plant lineages differ markedly in species richness globally, regionally, and locally. Differences in whole-genome characteristics (WGCs) such as monoploid chromosome number, genome size, and ploidy level may explain differences in global species richness through speciation or global extinction. However, it is unknown whether WGCs drive species richness within lineages also in a recent, postglacial regional flora, or in local plant communities, through local extinction or colonization and regional species turn-over. METHODS: We tested for relationships between WGCs and richness of angiosperm families across the Netherlands/Germany/Czechia as a region, and within 193449 local vegetation plots. KEY RESULTS: Families that are species-rich across the region have lower ploidy levels and small monoploid chromosomes numbers or both (interaction terms), but the relationships disappear after accounting for continental and local richness of families. Families that are species-rich within occupied localities have small numbers of polyploidy and monoploid chromosome numbers or both, independent of their own regional richness and the local richness of all other locally co-occurring species in the plots. Relationships between WGCs and family species-richness persisted after accounting for niche characteristics and life histories. CONCLUSIONS: Families that have few chromosomes, either monoploid or holoploid, succeed in maintaining many species in local communities and across a continent and, as indirect consequence of both, across a region. We suggest evolutionary mechanisms how small chromosome numbers and ploidy levels might decrease rates of local extinction and increase rates of colonization. The genome of a macroevolutionary lineage may ultimately control whether its species can ecologically coexist

Anthropogenic threats to evolutionary heritage of angiosperms in the Netherlands through an increase in high-competition environments

Present biodiversity comprises the evolutionary heritage of Earth's epochs. Lineages from particular epochs are often found in particular habitats, but whether current habitat decline threatens the heritage from particular epochs is unknown. We hypothesized that within a given region, humans threaten specifically habitats that harbor lineages from a particular geological epoch. We expect so because humans threaten environments that dominated and lineages that diversified during these epochs. We devised a new approach to quantify, per habitat type, diversification of lineages from different epochs. For Netherlands, one of the floristically and ecologically best-studied regions, we quantified the decline of habitat types and species in the past century. We defined habitat types based on vegetation classification and used existing ranking of decline of vegetation classes and species. Currently, most declining habitat types and the group of red-listed species are characterized by increased diversification of lineages dating back to Paleogene, specifically to Paleocene-Eocene and Oligocene. Among vulnerable habitat types with large representation of lineages from these epochs were sublittoral and eulittoral zones of temperate seas and 2 types of nutrient-poor, open habitats. These losses of evolutionary heritage would go unnoticed with classical measures of evolutionary diversity. Loss of heritage from Paleocene-Eocene became unrelated to decline once low competition, shade tolerance, and low proportion of non-Apiaceae were accounted for, suggesting that these variables explain the loss of heritage from Paleocene-Eocene. Losses of heritage from Oligocene were partly explained by decline of habitat types occupied by weak competitors and shade-tolerant species. Our results suggest a so-far unappreciated human threat to evolutionary heritage: habitat decline threatens descendants from particular epochs. If the trends persist into the future uncontrolled, there may be no habitats within the region for many descendants of evolutionary ancient epochs, such as Paleogene.</p

Ecologically diverse and distinct neighbourhoods trigger persistent phenotypic consequences, and amine metabolic profiling detects them

We thank Christian Huyghe for sampling plants in Jena and Magali Caillaud for setting up the experiment in Lusignan. We thank Soukaïnatou Aidara, Eléonore Crunchant and Frédéric Jean for help in biochemical analyses, Marie-Paule Briand (Centre Commun ABGC, UMR Ecobio) for C/N analyses and Valérie Briand for help in documentation.International audience* Global change triggers rapid alterations in the composition and diversity of plant communities which may change ecosystem functioning. Do changes in community diversity also change traits persistently, that is does coexistence with numerous or functionally or phylogenetically distinct species trigger, in a given focal species, trait shifts that persist? * We studied the grass Dactylis glomerata. Dactylis was grown in experimental plots with different species compositions for 5 years, sampled, cloned and grown in a common garden. We studied amines, regulators integrating growth responses of organisms to their environment. * We found that the mean levels and variances of most amines depended on the diversity of the source community, notably the species richness and the phylogenetic and functional distinctness from Dactylis, unbiased by species identity or biomass shifts. * Synthesis. Our results suggest that different levels of ambient diversity can, within a few years, select for different genotypes which have different compositions of growth regulators. Our study also suggests that a plant species can evolve in response to the diversity or distinctness of the surrounding plant community. Evolutionary changes of plant phenotypes might mediate an impact of past biological diversity on present ecosystem functionin