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Scientists have shown that the alpine plant Saxifraga candelabrum is genuinely carnivorous, confirming a hypothesis Charles Darwin advanced in 1875.
The findings were published in the journal Nature Communications on 4 August 2026.
The plant grows above about 2,500 metres in the Hengduan Mountains, which link the south-eastern Tibetan Plateau to the Yunnan-Guizhou Plateau.
Its stems and branches are covered in sticky glandular hairs that trap small insects, predominantly non-biting midges, and the plant was shown to digest and absorb nutrients from them.
Genetic analysis found similarities with other, independently evolved carnivorous plants, including genes linked to prey attraction, digestion and nutrient absorption.
Plenty of plants have sticky surfaces and plenty of insects die on them, but that alone does not make a plant carnivorous. Botanists require a chain of three things: the plant must attract or at least reliably capture prey, it must digest that prey by its own means or through partners, and it must absorb the resulting nutrients into its own tissue and benefit from them. A plant that merely traps insects and lets them rot is a passive flypaper, not a carnivore. That is precisely why Darwin's suggestion sat unresolved for a century and a half — the glandular hairs were visible to him in 1875, but demonstrating digestion and uptake requires tracing nutrients from the insect into the plant, which needs isotopic and molecular techniques he did not have. Carnivory in plants is an adaptation to nutrient-poor soils, especially where nitrogen and phosphorus are scarce, and it has evolved independently many times in unrelated lineages. That repeated independent origin is why the genetic finding matters: discovering the same functional gene sets in a plant from a completely different family is evidence of convergent evolution rather than shared ancestry.
Simple Analogy: A puddle that drowns insects is not a predator. It becomes one only if it catches them on purpose, breaks them down, and grows on the proceeds.
Charles Darwin proposes that Saxifraga rotundifolia and S. umbrosa may be insect-eaters, noting their sticky glandular hairs resemble those of known carnivorous plants
The hypothesis remains untested, as demonstrating digestion and nutrient uptake requires techniques unavailable to Darwin
A study in Nature Communications shows Saxifraga candelabrum captures, digests and absorbs nutrients from insects, and carries gene sets associated with carnivory
The Hengduan Mountains run north to south along the eastern edge of the Tibetan Plateau, linking it to the Yunnan-Guizhou Plateau in south-western China. The range is one of the world's recognised biodiversity hotspots, largely because its deep parallel river valleys and steep altitudinal gradients isolate populations and drive rapid speciation. Saxifraga candelabrum grows in its high alpine zone, above roughly 2,500 metres, where thin soils and low nutrient availability create exactly the conditions under which carnivory offers an advantage.
GS Paper 3 > Science and Technology; GS Paper 1 > Physical Geography: World Biodiversity Hotspots
General Awareness > General Science > Botany
General Awareness > General Science > Plant Biology
"Gynobasic style" is a characteristic feature of which family?
Answer: Lamiaceae (Labiatae)
A plant that captures prey, digests it and absorbs the resulting nutrients for its own growth — all three conditions being necessary.
A hair-like outgrowth on a plant surface that secretes a sticky or digestive substance; the structure Darwin noticed on Saxifraga.
The independent evolution of similar traits in unrelated lineages, illustrated here by carnivory arising separately in different plant families.
A north-south range in south-western China linking the south-eastern Tibetan Plateau to the Yunnan-Guizhou Plateau, recognised as a biodiversity hotspot.
Soil deficient in nitrogen and phosphorus; the selection pressure under which plant carnivory typically evolves.