The plant evolves to become less visible to humans

A plant used in traditional Chinese medicine has evolved to be less visible to humans, new research shows.

Scientists have found that plants of Fritillaria delavayi, which live on the rocky slopes of China’s Hengduan Mountains, most closely match their origins in areas where they are heavily harvested.

This suggests that humans are “driving” the evolution of this species to new color forms because better camouflaged plants have a greater chance of survival.

The study was carried out by the Kunming Institute of Botany (Chinese Academy of Sciences) and the University of Exeter.

“It is remarkable how humans can have such a direct and dramatic impact on the coloring of wild organisms, not only on their survival, but on their evolution itself,” said Professor Martin Stevens, of the Center for Ecology and Conservation at the Penryn campus in Exeter. in Cornwall.

“Many plants seem to use camouflage to hide from herbivores who may eat them – but here we see camouflage evolving in response to human collectors.

“It is possible that humans have driven the evolution of defensive strategies in other plant species, but surprisingly little research has examined this.

In the new study, the researchers measured how well plants from different populations matched their mountain environment and how easy they were to collect, and spoke to local people to estimate how much harvest was done at each location.

They found that the level of camouflage in plants correlated with harvest levels.

In a computer experiment, more camouflaged plants also took longer to be detected by humans.

Fritillaria delavayi is a perennial herb that has leaves – varying in color from gray to brown to green – at a young age, and produces a single flower per year after the fifth year.

The bulb of the fritillary species has been used in Chinese medicine for over 2000 years and the high prices in recent years have led to increased harvests.

“Like other camouflaged plants that we studied, we thought that the camouflage evolution of this fritillary was driven by herbivores, but we did not find such animals,” said Dr Yang Niu, of Kunming Institute of Botany. “Then we realized that humans could be the reason.”

Professor Hang Sun, Kunming Institute of Botany, added, “Commercial harvest is a much stronger selection pressure than many pressures in nature.” The current state of biodiversity on earth is shaped both by nature and by ourselves. “

The paper, published in the journal Current biology, is titled: “Commercial Harvest Led to the Evolution of Camouflage in an Alpine Plant.”