Flowering Plants Face Extinction Risk for 21.2% of Evolutionary History

Understanding the EDGE Approach

The EDGE method, established in 2007 by the Zoological Society of London, provides a framework for prioritizing conservation efforts. It combines a species’ evolutionary distinctiveness (ED)—how much it represents a long, isolated branch on the evolutionary tree—with its risk of global endangerment (GE). According to Félix Forest, a plant evolutionary biologist at Kew Gardens and lead author of the study, these scores are vital for identifying irreplaceable species that are frequently overlooked. While the approach has been used for animals for nearly two decades, its application to plants is helping researchers better understand how to protect ecosystems that have taken billions of years to develop.

Irreplaceable Species at Risk

The list of threatened species includes both well-known plants and obscure, rare varieties. Scientists emphasize that the benefits these species provide to society are as unique and irreplaceable as the plants themselves.

Broader Challenges to Plant Survival

The threat to flowering plants extends beyond immediate extinction risks to the complex ways plants adapt to a changing environment. A 2026 study from the University of Michigan, published by researchers including S.G.D. Bishop and Regina Baucom, examined how morning glories are evolving in response to human-caused global change. The study found that these plants are increasingly “locked” into a trajectory that favors attracting pollinators through larger flowers, potentially at the expense of their ability to adapt to climate change. Over a nine-year period, the population’s rate of adaptation decreased by 96 percent. This suggests that as pollinator populations decline due to environmental changes and human activity, plants may struggle to shift their traits—such as flowering time—to keep pace with changing temperatures and precipitation.

The Intersection of Knowledge and Loss

The crisis is compounded by the loss of human knowledge regarding plant utility. A separate study focusing on the Amazon basin highlights that Indigenous communities rely on thousands of native plant species for food, medicine, and building materials. Researchers found that plant knowledge is often tied to specific Indigenous languages. Because many of these languages are threatened, the study projects that a significant portion of traditional botanical knowledge could vanish alongside the plants themselves. The researchers noted that the loss of plants and the loss of the languages used to describe them often occur within the same generation, as the threats of climate change and environmental degradation strike both the ecosystem and the cultures that depend on it.

A Call for Monitoring and Action

While the outlook is concerning, researchers view the identification of these distinct, threatened species as an opportunity to allocate limited resources where they can make the greatest difference to global biodiversity. Each plant is an essential, living building block to life on Earth, providing us with air to breathe and food to eat, said Rikki Gumbs, a biologist from the Zoological Society in London and co-lead on the paper.