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Writing / Irene Vega
The fifth report of State of the World's, prepared by the Royal Botanical Garden of Kew (Hereinafter Kew o Kew Gardens) of London, exposes the current condition of the world's plants and fungi worldwide. Based on the work of 200 international researchers, it covers the content of more than 25 cutting-edge scientific articles in its 11 chapters. The new report examines the global drivers and patterns of biodiversity, as well as critical knowledge gaps and how to address them.
In this year's report, with the theme "Facing the emergency of the natural world: evidence, lack of data and priorities", the different research groups analyze in depth what is known and what is still unknown about the diversity of these fundamental components for ecosystems and the threats they face.
The underlying scientific evidence has recently been published in a special collection of the journals New Phytologist and Plants, People, Planet entitled 'Global Plant Diversity and Distribution' and in a review of global fungal diversity and conservation published by the journal Annual Review of Environment and Resources.
With some 350.000 species of vascular plants already known to science, the scientific community is immersed in a race against time to name and evaluate those that have not yet been described. But the challenge is immense: up to 100.000 more species have yet to be formally named and new estimates suggest that up to 3 in 4 undescribed vascular plants are likely already at risk of extinction. Furthermore, estimates indicate that 45% of all known flowering plant species could be facing extinction. The families of orchidaceae (orchids); Piperaceae, which includes black pepper; bromeliads, which includes pineapple; and araceae, which includes many important crops, are among the most threatened.
Based on these findings, research staff at Kew calls for all newly described species to be treated as if they had been assessed as threatened, unless proven otherwise. And they also hope that these new results can guide policymakers and conservation efforts to save plants that are on the brink of extinction, accelerating extinction risk assessments for these species.
Use DNA to explore the past of plants
The research led by Tamara Villaverde, a URJC professor in the area of Biodiversity and Conservation, has resolved the oldest evolutionary relationships within the Scrofulariaceae, a family with nearly 2000 species, which includes many ornamental and medicinal plants. “This family has traditionally been a 'catch-all' with species with very different morphology and difficult classification,” explains Isabel Sanmartín, co-author of the work and researcher at the Royal Botanical Garden of Madrid, current vice director of Research and Collections at this institute. CSIC. “To do this, we have used genomic techniques that allow us to obtain the DNA sequence of hundreds of genes from the nucleus and chloroplast, even from old herbarium specimens. “Our genomic results indicate that there are two main lineages of very different sizes: the first contains 11 genera and 340 species (17% of the total species in the family) and the second includes 24 genera and 1.700 species (83%),” he adds. Tamara Villaverde.
Furthermore, the results obtained suggest that the evolutionary history of scrofulariaceae began about 66 million years ago in the ancient supercontinent of Gondwana, at a geological moment coinciding with the extinction of more than 75% of the species that inhabited the Earth. This period also coincides with an increase in gender diversity and the emergence of many of the tribes. Specifically, the study carried out by the URJC researcher and her collaborators has involved the description of two new tribes for the family: one of them includes a single species (present in Madagascar), while the other tribe includes three species with a distribution unusual (Namibia, Horn of Africa and Canary Islands). “These lineages are probably the remnant of evolutionary lineages with greater diversity in the past, in which climate change in geological times led to the extinction of their closest conspecifics. Likewise, the resolution of kinship relationships within this family allows us to better understand its evolution and will contribute to the discovery of new species of economic value,” explain Isabel Sanmartín and Tamara Villaverde.
Based on these results, it is suggested that it is necessary to protect the areas where these species are found to maintain the biodiversity of the regions they inhabit. “Many of these regions are considered biodiversity 'hot spots', where human activity poses a threat to a large number of species. Furthermore, some of the scrofulariaceae tribes constitute unique evolutionary lines, branches of the Tree of Life, which have evolved independently for millions of years, and therefore present unique morphological, physiological, or behavioral traits, which would be lost if this taxon becomes extinct." , the researchers conclude.