Reproductive character displacement and potential underlying drivers in a species-rich and florally diverse lineage of tropical angiosperms (; Acanthaceae).

Reproductive character displacement is a pattern whereby sympatric lineages diverge more in reproductive character morphology than allopatric lineages. This pattern has been observed in many plant species, but comparably few have sought to disentangle underlying mechanisms. Here, in a diverse lineage of Neotropical plants (; Acanthaceae), we present evidence of reproductive character displacement in a macroevolutionary framework (i.

Phylogenomics reveals convergent evolution of red-violet coloration in land plants and the origins of the anthocyanin biosynthetic pathway.

The flavonoids, one of the largest classes of plant secondary metabolites, are found in lineages that span the land plant phylogeny and play important roles in stress responses and as pigments. Perhaps the most well-studied flavonoids are the anthocyanins that have human health benefits and help plants attract pollinators, regulate hormone production, and confer resistance to abiotic and biotic stresses. The canonical biochemical pathway responsible for the production of these pigments is well-characterized for flowering plants yet its conservation across deep divergences in land plants remains debated and poorly understood.

A taxonomically broad metagenomic survey of 339 species spanning 57 families suggests cystobasidiomycete yeasts are not ubiquitous across all lichens.

Premise: Lichens are fungi that enter into obligate symbioses with photosynthesizing organisms (algae, cyanobacteria). Traditional narratives of lichens as binary symbiont pairs have given way to their recognition as dynamic metacommunities. Basidiomycete yeasts, particularly of the genus Cyphobasidium, have been inferred to be widespread and important components of lichen metacommunities.

Habitat quality and disturbance drive lichen species richness in a temperate biodiversity hotspot.

The impacts of disturbance on biodiversity and distributions have been studied in many systems. Yet, comparatively less is known about how lichens-obligate symbiotic organisms-respond to disturbance. Successful establishment and development of lichens require a minimum of two compatible yet usually unrelated species to be present in an environment, suggesting disturbance might be particularly detrimental.

Genome streamlining via complete loss of introns has occurred multiple times in lichenized fungal mitochondria.

Reductions in genome size and complexity are a hallmark of obligate symbioses. The mitochondrial genome displays clear examples of these reductions, with the ancestral alpha-proteobacterial genome size and gene number having been reduced by orders of magnitude in most descendent modern mitochondrial genomes. Here, we examine patterns of mitochondrial evolution specifically looking at intron size, number, and position across 58 species from 21 genera of lichenized Ascomycete fungi, representing a broad range of fungal diversity and niches.

Evolutionary and ecological drivers of plant flavonoids across a large latitudinal gradient.

Flavonoids are important secondary metabolites that play an integral role in protecting plants against UV radiation and other forms of environmental stress. Given widespread impacts of environmental effects associated with latitude on a multitude of biological systems and a well-documented increase in solar radiation towards the equator, plant flavonoid production is expected to increase as a response to factors associated with decreasing latitude. Using data from a Neotropical genus (Ruellia) that spans an exceptionally broad latitudinal gradient, we tested a hypothesis of a positive latitudinal gradient in flavonoid concentration and assessed other factors that influence flavonoid production including habitat type (xeric vs.

Genomic insights into the mitochondria of 11 eastern North American species of .

is among the most species-rich genera of lichens globally. Species in this lineage, commonly referred to as reindeer lichens, are ecologically important in numerous regions worldwide. In some locations, species of can comprise the dominant groundcover, and are a major food source for caribou and other mammals.

The complete mitochondrial genomes of five lichenized fungi in the genus (Ascomycota: Parmeliaceae).

Known colloquially as 'Old Man's Beard', is a genus of lichenized Ascomycete fungi characterized by having a fruticose growth form and cartilaginous central axis. The complete mitochondrial genomes of , , , , and were sequenced using Illumina data and then assembled . These mitogenomes ranged in size from 52,486 bp () to 94,464 bp ().

Reductions in complexity of mitochondrial genomes in lichen-forming fungi shed light on genome architecture of obligate symbioses.

Symbioses among co-evolving taxa are often marked by genome reductions such as a loss of protein-coding genes in at least one of the partners as a means of reducing redundancy or intergenomic conflict. To explore this phenomenon in an iconic yet under-studied group of obligate symbiotic organisms, mitochondrial genomes of 22 newly sequenced and annotated species of lichenized fungi were compared to 167 mitochondrial genomes of nonlichenized fungi. Our results demonstrate the first broad-scale loss of atp9 from mitochondria of lichenized fungi.

RADseq dataset with 90% missing data fully resolves recent radiation of (Acanthaceae) in the ultra-arid deserts of Namibia.

Deserts, even those at tropical latitudes, often have strikingly low levels of plant diversity, particularly within genera. One remarkable exception to this pattern is the genus (Acanthaceae), in which 37 of 40 named species occupy one of the driest environments on Earth, the Namib Desert of Namibia and neighboring Angola. To contribute to understanding this enigmatic diversity, we generated RADseq data for 47 accessions of representing 22 species.

Reshaping Darwin's Tree: Impact of the Symbiome.

Much of the undescribed biodiversity on Earth is microbial, often in mutualistic or pathogenic associations. Physically associated and coevolving life forms comprise a symbiome. We propose that systematics research can accelerate progress in science by introducing a new framework for phylogenetic analysis of symbiomes, here termed SYMPHY (symbiome phylogenetics).

Disentangling geographical, biotic, and abiotic drivers of plant diversity in neotropical Ruellia (Acanthaceae).

It has long been hypothesized that biotic interactions are important drivers of biodiversity evolution, yet such interactions have been relatively less studied than abiotic factors owing to the inherent complexity in and the number of types of such interactions. Amongst the most prominent of biotic interactions worldwide are those between plants and pollinators. In the Neotropics, the most biodiverse region on Earth, hummingbird and bee pollination have contributed substantially to plant fitness.

The draft genome of Ruellia speciosa (Beautiful Wild Petunia: Acanthaceae).

The genus Ruellia (Wild Petunias; Acanthaceae) is characterized by an enormous diversity of floral shapes and colours manifested among closely related species. Using Illumina platform, we reconstructed the draft genome of Ruellia speciosa, with a scaffold size of 1,021 Mb (or ∼1.02 Gb) and an N50 size of 17,908 bp, spanning ∼93% of the estimated genome (∼1.

Genome-scale transcriptional study of hybrid effects and regulatory divergence in an F hybrid Ruellia (Wild Petunias: Acanthaceae) and its parents.

Background: New combinations of divergent genomes can give rise to novel genetic functions in resulting hybrid progeny. Such functions may yield opportunities for ecological divergence, contributing ultimately to reproductive isolation and evolutionary longevity of nascent hybrid lineages. In plants, the degree to which transgressive genotypes contribute to floral novelty remains a question of key interest.

A rich fossil record yields calibrated phylogeny for Acanthaceae (Lamiales) and evidence for marked biases in timing and directionality of intercontinental disjunctions.

More than a decade of phylogenetic research has yielded a well-sampled, strongly supported hypothesis of relationships within the large ( > 4000 species) plant family Acanthaceae. This hypothesis points to intriguing biogeographic patterns and asymmetries in sister clade diversity but, absent a time-calibrated estimate for this evolutionary history, these patterns have remained unexplored. Here, we reconstruct divergence times within Acanthaceae using fossils as calibration points and experimenting with both fossil selection and effects of invoking a maximum age prior related to the origin of Eudicots.

Origin of African Physacanthus (Acanthaceae) via wide hybridization.

Gene flow between closely related species is a frequent phenomenon that is known to play important roles in organismal evolution. Less clear, however, is the importance of hybridization between distant relatives. We present molecular and morphological evidence that support origin of the plant genus Physacanthus via "wide hybridization" between members of two distantly related lineages in the large family Acanthaceae.

Comparative anatomy, morphology, and molecular phylogenetics of the African genus Satanocrater (Acanthaceae).

Premise Of The Study: Anatomical and morphological features of Satanocrater were studied to test hypotheses of xeric adaptations in the genus, which is endemic to arid tropical Africa. These features, together with molecular data, were used to test the phylogenetic placement of Satanocrater within the large plant family Acanthaceae.

Methods: We undertook a comparative study of four species of Satanocrater.

Is floral specialization an evolutionary dead-end? Pollination system transitions in Ruellia (Acanthaceae).

Pollination systems frequently reflect adaptations to particular groups of pollinators. Such systems are indicative of evolutionary specialization and have been important in angiosperm diversification. We studied the evolution of pollination systems in the large genus Ruellia.