Selection maintains a nonadaptive floral polyphenism.

Adaptive phenotypic plasticity evolves in response to the contrasting selection pressures that arise when organisms face environmental heterogeneity. Despite its importance for understanding how organisms successfully cope with environmental change, adaptive plasticity is often assumed but rarely demonstrated. We study here the adaptive nature of the extreme seasonal within-individual floral polyphenism exhibited by the crucifer , a Mediterranean species that produces two different types of flowers depending on the season of the year.

The role of phenotypic plasticity in shaping ecological networks.

Plasticity-mediated changes in interaction dynamics and structure may scale up and affect the ecological network in which the plastic species are embedded. Despite their potential relevance for understanding the effects of plasticity on ecological communities, these effects have seldom been analysed. We argue here that, by boosting the magnitude of intra-individual phenotypic variation, plasticity may have three possible direct effects on the interactions that the plastic species maintains with other species in the community: may expand the interaction niche, may cause a shift from one interaction niche to another or may even cause the colonization of a new niche.

Lack of ITS sequence homogenization in Erysimum species (Brassicaceae) with different ploidy levels.

The internal transcribed spacers (ITS) exhibit concerted evolution by the fast homogenization of these sequences at the intragenomic level. However, the rate and extension of this process are unclear and might be conditioned by the number and divergence of the different ITS copies. In some cases, such as hybrid species and polyploids, ITS sequence homogenization appears incomplete, resulting in multiple haplotypes within the same organism.

Satellitome comparison of two oedipodine grasshoppers highlights the contingent nature of satellite DNA evolution.

Background: The full catalog of satellite DNA (satDNA) within a same genome constitutes the satellitome. The Library Hypothesis predicts that satDNA in relative species reflects that in their common ancestor, but the evolutionary mechanisms and pathways of satDNA evolution have never been analyzed for full satellitomes. We compare here the satellitomes of two Oedipodine grasshoppers (Locusta migratoria and Oedaleus decorus) which shared their most recent common ancestor about 22.

Phenotypic plasticity guides Moricandia arvensis divergence and convergence across the Brassicaceae floral morphospace.

Many flowers exhibit phenotypic plasticity. By inducing the production of several phenotypes, plasticity may favour the rapid exploration of different regions of the floral morphospace. We investigated how plasticity drives Moricandia arvensis, a species displaying within-individual floral polyphenism, across the floral morphospace of the entire Brassicaceae family.

Asymmetric Reproductive Barriers and Gene Flow Promote the Rise of a Stable Hybrid Zone in the Mediterranean High Mountain.

Hybrid zones have the potential to shed light on evolutionary processes driving adaptation and speciation. Secondary contact hybrid zones are particularly powerful natural systems for studying the interaction between divergent genomes to understand the mode and rate at which reproductive isolation accumulates during speciation. We have studied a total of 720 plants belonging to five populations from two (Brassicaceae) species presenting a contact zone in the Sierra Nevada mountains (SE Spain).

Within-individual phenotypic plasticity in flowers fosters pollination niche shift.

Phenotypic plasticity, the ability of a genotype of producing different phenotypes when exposed to different environments, may impact ecological interactions. We study here how within-individual plasticity in Moricandia arvensis flowers modifies its pollination niche. During spring, this plant produces large, cross-shaped, UV-reflecting lilac flowers attracting mostly long-tongued large bees.

Promoting Individual and Collective Creativity in Science Students.

Creativity is a scientific skill necessary to develop a successful research career. We expose the importance of a growth mindset, divergent, lateral, and associative thinking, serendipity, and being part of a nonhierarchical and diverse research team to improve both individual and collective creativity.

Independent evolution of ancestral and novel defenses in a genus of toxic plants (, Brassicaceae).

Phytochemical diversity is thought to result from coevolutionary cycles as specialization in herbivores imposes diversifying selection on plant chemical defenses. Plants in the speciose genus (Brassicaceae) produce both ancestral glucosinolates and evolutionarily novel cardenolides as defenses. Here we test macroevolutionary hypotheses on co-expression, co-regulation, and diversification of these potentially redundant defenses across this genus.

Interpopulation spread of a parasitic B chromosome is unlikely through males in the grasshopper Eyprepocnemis plorans.

The near-neutral model of B chromosome evolution predicts that population invasion is quite fast. To test this prediction, in 1994, we introduced males of the grasshopper Eyprepocnemis plorans from a B-carrying population into a B-lacking population and monitored the evolution of B-chromosome frequency up to 2013. We observed fluctuating very low B frequency across years but, remarkably, the B chromosome introduced (the B2 variant) was found up to 1996 only, whereas the B1 variant was present from 1996 onwards, presumably introduced by fishermen using E.

Pollination effectiveness in a generalist plant: adding the genetic component.

The pollination effectiveness of a flower visitor has traditionally been measured as the product of a quantity component that depends on the frequency of interaction and a quality component that measures the per-visit effects on plant reproduction. We propose that this could be complemented with a genetic component informing about each pollinator's contribution to the genetic diversity and composition of the plant progeny. We measured the quantity and quality components of effectiveness of most pollinator functional groups of the generalist herb Erysimum mediohispanicum.

Anther Rubbing, a New Mechanism That Actively Promotes Selfing in Plants.

Self-fertilization has recurrently evolved in plants, involving different strategies and traits and often loss of attractive functions, collectively known as the selfing syndrome. However, few traits that actively promote self-fertilization have been described. Here we describe a novel mechanism promoting self-fertilization in the Brassicaceae species Erysimum incanum.

Comparative assessment shows the reliability of chloroplast genome assembly using RNA-seq.

Chloroplast genomes (cp genomes) are widely used in comparative genomics, population genetics, and phylogenetic studies. Obtaining chloroplast genomes from RNA-Seq data seems feasible due to the almost full transcription of cpDNA. However, the reliability of chloroplast genomes assembled from RNA-Seq instead of genomic DNA libraries remains to be thoroughly verified.

Long-term monitoring of B-chromosome invasion and neutralization in a population of Prospero autumnale (Asparagaceae).

B chromosomes have been reported in about 15% of eukaryotes, but long-term dynamics of B chromosomes in a single natural population has rarely been analyzed. Prospero autumnale plants collected in 1981 and 1983 at Cuesta de La Palma population had shown the presence of B chromosomes. We analyze here seven additional samples collected between 1987 and 2015, and show that B frequency increased significantly during the 1980s and showed minor fluctuations between 2005 and 2015.

Molecular phylogeny and evolutionary history of DC (Brassicaceae).

Background: The phylogeny of tribe Brassiceae (Brassicaceae) has not yet been resolved because of its complex evolutionary history. This tribe comprises economically relevant species, including the genus DC. This genus is currently distributed in North Africa, Middle East, Central Asia and Southern Europe, where it is associated with arid and semi-arid environments.

Timing of the evolutionary history of Corallinaceae (Corallinales, Rhodophyta).

The temporal dimension of the most recent Corallinaceae (order Corallinales) phylogeny was presented here, based on first occurrence time estimates from the fossil record. Calibration of the molecular clock of the genetic marker SSU entailed a separation of Corallinales from Hapalidiales in the Albian (Early Cretaceous ~105 mya). Neither the calibration nor the fossil record resolved the succession of appearance of the first three emerging subfamilies: Mastophoroideae, Corallinoideae, and Neogoniolithoideae.

Inter-annual maintenance of the fine-scale genetic structure in a biennial plant.

Within plant populations, space-restricted gene movement, together with environmental heterogeneity, can result in a spatial variation in gene frequencies. In biennial plants, inter-annual flowering migrants can homogenize gene frequencies between consecutive cohorts. However, the actual impact of these migrants on spatial genetic variation remains unexplored.

Phylogenetic relationships of corallinaceae (Corallinales, Rhodophyta): taxonomic implications for reef-building corallines.

A new, more complete, five-marker (SSU, LSU, psbA, COI, 23S) molecular phylogeny of the family Corallinaceae, order Corallinales, shows a paraphyletic grouping of seven well-supported monophyletic clades. The taxonomic implications included the amendment of two subfamilies, Neogoniolithoideae and Metagoniolithoideae, and the rejection of Porolithoideae as an independent subfamily. Metagoniolithoideae contained Harveylithon gen.

The role of pollinators in the evolution of corolla shape variation, disparity and integration in a highly diversified plant family with a conserved floral bauplan.

Background And Aims: Brassicaceae is one of the most diversified families in the angiosperms. However, most species from this family exhibit a very similar floral bauplan. In this study, we explore the Brassicaceae floral morphospace, examining how corolla shape variation (an estimation of developmental robustness), integration and disparity vary among phylogenetically related species.

Geographical Barriers Impeded the Spread of a Parasitic Chromosome.

Parasitic supernumerary (B) chromosomes show high capability to spread across populations. But the existence of abrupt discontinuities in their distribution demands an explanation. The grasshopper Eyprepocnemis plorans plorans harbour supernumerary chromosomes in all natural populations hitherto analyzed from the Circum-Mediterranean region, with the single exception of the headwaters of the Iberian Segura River and several of its tributaries.

The role of pollinators in floral diversification in a clade of generalist flowers.

Pollinator-mediated evolutionary divergence has seldom been explored in generalist clades because it is assumed that pollinators in those clades exert weak and conflicting selection. We investigate whether pollinators shape floral diversification in a pollination generalist plant genus, Erysimum. Species from this genus have flowers that appeal to broad assemblages of pollinators.

Possible introgression of B chromosomes between bee species (Genus Partamona ).

The origin of supernumerary (B) chromosomes is still a debated topic, with intra- and interspecific origins being the most plausible options. In the bee Partamona helleri, a sequence-characterized amplified region (SCAR) marker being specific to B chromosomes suggested the possibility of interspecific origin. Here, we search for this marker in 3 close relative species and perform DNA sequence comparison between species.

Intragenomic distribution of RTE retroelements suggests intrachromosomal movement.

Much is known about the abundance of transposable elements (TEs) in eukaryotic genomes, but much is still unknown on their behaviour within cells. We employ here a combination of cytological, molecular and genomic approaches providing information on the intragenomic distribution and behaviour of non-long terminal repeat (LTR) retrotransposon-like elements (RTE). We microdissected every chromosome in a single first meiotic metaphase cell of the grasshopper Eyprepocnemis plorans and polymerase chain reaction (PCR) amplified a fragment of the RTE reverse transcriptase gene with specific primers.