Over 125 million years of ant-plant interactions have culminated in one of the most intriguing evolutionary outcomes in life history. The myrmecophyte Duroia hirsuta (Rubiaceae) is known for its mutualistic association with the ant Myrmelachista schumanni and several other species, mainly Azteca, in the north-western Amazon. While both ants provide indirect defences to plants, only M.
View Article and Find Full Text PDFExposure to ultraviolet radiation (UVR) is harmful to living cells, leading organisms to evolve protective mechanisms against UVR-induced cellular damage and stress. UVR, particularly UVB (280-320 nm), can damage proteins and DNA, leading to errors during DNA repair and replication. Excessive UVR can induce cellular death.
View Article and Find Full Text PDFUltraviolet radiation (UVR) and its deleterious effects on living cells selects for UVR-protective mechanisms. Organisms across the tree of life evolved a variety of natural sunscreens to prevent UVR-induced cellular damage and stress. However, in vertebrates, only melanin is known to act as a sunscreen.
View Article and Find Full Text PDFThe mushroom genus is best known as the core group of psychoactive mushrooms, yet basic information on their diversity, taxonomy, chemistry, and general biology is still largely lacking. In this study, we reexamined 94 fungarium specimens, representing 18 species, by DNA barcoding, evaluated the stability of psilocybin, psilocin, and their related tryptamine alkaloids in 25 specimens across the most commonly vouchered species (Psilocybe cubensis, Psilocybe cyanescens, and Psilocybe semilanceata), and explored the metabolome of cultivated . Our data show that, apart from a few well-known species, the taxonomic accuracy of specimen determinations is largely unreliable, even at the genus level.
View Article and Find Full Text PDFPlants are widely recognized as chemical factories, with each species producing dozens to hundreds of unique secondary metabolites. These compounds shape the interactions between plants and their natural enemies. We explore the evolutionary patterns and processes by which plants generate chemical diversity, from evolving novel compounds to unique chemical profiles.
View Article and Find Full Text PDFIn species-rich regions and highly speciose genera, the need for species identification and taxonomic recognition has led to the development of emergent technologies. Here, we combine long-term plot data with untargated metabolomics, and morphological and phylogenetic data to describe a new rare species in the hyperdiverse genus of trees Mill. Our combined data show that is a new lineage splitting from their closest relatives and .
View Article and Find Full Text PDFTropical forests sustain many ant species whose mating events often involve conspicuous flying swarms of winged gynes and males. The success of these reproductive flights depends on environmental variables and determines the maintenance of local ant diversity. However, we lack a strong understanding of the role of environmental variables in shaping the phenology of these flights.
View Article and Find Full Text PDFSaplings in the shade of the tropical understorey face the challenge of acquiring sufficient carbon for growth as well as defence against intense pest pressure. A minor increase in light availability via canopy thinning may allow for increased investment in chemical defence against pests, but it may also necessitate additional biochemical investment to prevent light-induced oxidative stress. The shifts in secondary metabolite composition that increased sun exposure may precipitate in such tree species present an ideal milieu for evaluating the potential of a single suite of phenolic secondary metabolites to be used in mitigating both abiotic and biotic stressors.
View Article and Find Full Text PDFEcological theory predicts that the high local diversity observed in tropical forests is maintained by negative density-dependent interactions within and between closely related plant species. By using long-term data on tree growth and survival for coexisting (Fabaceae, Mimosoideae) congeners, we tested two mechanisms thought to underlie negative density dependence (NDD): competition for resources and attack by herbivores. We quantified the similarity of neighbors in terms of key ecological traits that mediate these interactions, as well as the similarity of herbivore communities.
View Article and Find Full Text PDFCoevolutionary theory has long predicted that the arms race between plants and herbivores is a major driver of host selection and diversification. At a local scale, plant defenses contribute significantly to the structure of herbivore assemblages and the high alpha diversity of plants in tropical rain forests. However, the general importance of plant defenses in host associations and divergence at regional scales remains unclear.
View Article and Find Full Text PDFThe need for species identification and taxonomic discovery has led to the development of innovative technologies for large-scale plant identification. DNA barcoding has been useful, but fails to distinguish among many species in species-rich plant genera, particularly in tropical regions. Here, we show that chemical fingerprinting, or 'chemocoding', has great potential for plant identification in challenging tropical biomes.
View Article and Find Full Text PDFSelective pressures imposed by herbivores are often positively correlated with investments that plants make in defense. Research based on the framework of an evolutionary arms race has improved our understanding of why the amount and types of defenses differ between plant species. However, plant species are exposed to different selective pressures during the life of a leaf, such that expanding leaves suffer more damage from herbivores and pathogens than mature leaves.
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