The Chinese flower has evolved to be less visible to pickers | Environment

For thousands of years, the delicate Fritillaria delavayi it grew slowly on the rocky slopes of the Hengduan Mountains in China, producing a bright green flower after its fifth year.

But the conspicuous little plant has a deadly enemy: the people, who harvest the flower for traditional Chinese medicine.

With the intensification of commercial collection, Fritillaria delavayi has vanished – evolving rapidly to produce gray and brown leaves and flowers that cannot be seen so easily by foragers.

Scientists found that the color of the plant’s leaves became more camouflaged, matching the background rocks they grow on, in areas where there is more harvest pressure from people.

“Like other camouflaged plants we have studied, we thought this fritillary’s camouflage evolution was driven by herbivores, but we did not find such animals,” said Dr. Yang Niu, of the Kunming Institute of Botany, and co-author of the study. in Current Biology. “Then we realized that the reason could have been that of humans.”

In the study by the Kunming Institute of Botany (Chinese Academy of Sciences) and the University of Exeter, the researchers measured how well plants from different populations matched their mountain environment and how easy they were to harvest, and interviewed local people to estimate what has been gathered has taken place everywhere.

In a computer experiment, it was found that people take longer to discover the most camouflaged plants, suggesting that humans are driving the rapid evolution of this species into new color forms because better camouflaged plants have a better chance of survival. .

Fritillaria delavayi is a perennial herb that grows leaves at a young age before producing a single flower after its fifth year each June. The bulb of the fritillary species has been used in traditional Chinese medicine for over 2,000 years, but high prices in recent years have led to an increase in the yield.

“It is extraordinary to see how humans can have such a direct and dramatic impact on the coloration of wild organisms, not just their survival but their own evolution,” said Prof Martin Stevens, of the Center for Ecology and Conservation at the University of Exeter. “Many plants appear to use mimicry to hide from herbivores who might eat them, but here we see the evolution of camouflage in response to human collectors.

“It is possible that humans have led the evolution of defense strategies in other plant species, but surprisingly little research has examined it.”