Fri. May 24th, 2024

A groundbreaking report from Kew Gardens in the UK has disclosed a deeply concerning reality: more than 75% of the world’s “undescribed” plant species face the imminent threat of extinction.

This revelation, based on a major collaborative effort by over 200 international researchers and 25 scientific papers, underscores the urgency of addressing the crises of biodiversity loss and climate change.

The report, titled “Kew’s Fifth ‘State of the World’s Plants and Fungi,'” was published on October 10th and serves as a comprehensive synthesis of the latest research while identifying critical knowledge gaps in the field.

Professor Alexandre Antonelli, Director of Science at Royal Botanic Gardens (RBG) Kew, emphasized the need for rapid action to bridge these gaps and prioritize conservation efforts. He stated, “At a time when plants and fungi are increasingly under threat, we need to act fast to fill knowledge gaps and identify priorities for conservation.”

The report highlights key findings and developments, including the global commitment at COP15 to reduce the extinction rate of all species through the Kunming-Montreal Global Biodiversity Framework. However, a fundamental question persists: how many plant and fungi species exist globally?

Two significant advances are bringing us closer to an answer. The “World Checklist of Vascular Plants (WCVP),” compiled over 35 years by Belgian botanist Rafaël Govaerts, provides a comprehensive list of vascular plants from around the world. This achievement is seen as a realization of Charles Darwin’s dream of cataloging all plant species.

Additionally, environmental DNA analysis of soil samples worldwide has offered valuable insights into fungal diversity. While only 155,000 species of fungi have been formally named to date, technological advancements, such as DNA metabarcoding, have enabled scientists to estimate that there are approximately 2.5 million fungal species globally. This revelation implies that over 90% of fungal species remain undiscovered, with only 0.02% assessed for their global extinction threat level.

Dr. Tuula Niskanen from the University of Helsinki underscores the importance of naming and describing species, emphasizing that it is the first step in documenting life on Earth. Understanding a species enables researchers to share information, assess its conservation status, and explore its potential benefits to humanity.

Plants and fungi are fundamental to sustaining life on Earth, providing essential ecosystem services that support human livelihoods and contribute to food, medicine, clothing, and raw materials. With only approximately 10% of the world’s fungal biodiversity described, we may be overlooking species with transformative functions, such as enzymes that can break down plastics.

The report further reveals a critical concern regarding “vascular” plants, which include the majority of plant species. Around 350,000 of these species are known to science, but as many as 100,000 remain unnamed. Alarmingly, as many as three in four of these undescribed vascular plants are already threatened with extinction, as indicated by an analysis of data from the WCVP and the IUCN Red List of Threatened Species.

The relationship between the year of formal species description and its extinction risk is evident, with more than 77% of species described in 2020 meeting criteria for assessment as threatened. For flowering plants, researchers estimate that 45% of known species may be at risk of extinction, with orchids, Bromeliaceae, Piperaceae, and Araceae among the most imperiled plant families.

A poignant example is the “orchid of the falls,” collected in Guinea in 2018 but likely already extinct due to the flooding of its habitat by a hydroelectric dam. Dr. Martin Cheek, Senior Research Leader in Accelerated Taxonomy at Kew, notes the shockingly increased number of threatened plants in recent years.

In light of these findings, Kew scientists advocate for treating all newly described species as potentially threatened unless proven otherwise. Many newly described species have limited geographic ranges and declining populations, making them vulnerable. This approach is expected to provide greater protection for tens of thousands of yet-undescribed threatened species by expediting their assessment on the IUCN Red List.

Simultaneously, Kew scientists are working to address “biodiversity dark spots” worldwide, focusing on areas with limited data on plant diversity and distribution. Of the 32 identified dark spots, 44% are in tropical Asia, highlighting the need for further fieldwork and research in these regions.