For thousands of years, the dainty Fritillaria delavayi has grown slowly on the rocky slopes of the Hengduan mountains in China, producing a bright green flower after its fifth year.
The conspicuous small plant has one deadly enemy: people, who harvest the flower for traditional Chinese medicine.
As commercial harvesting has intensified, Fritillaria delavayi has vanished — by rapidly evolving to produce gray and brown leaves and flowers that cannot be so easily seen by pickers.
Scientists have discovered that the color of the plant’s leaves has become more camouflaged — matching the background rocks on which they grow — in areas where there is more harvesting pressure from people.
“Like other camouflaged plants we have studied, we thought the evolution of camouflage of this fritillary had been driven by herbivores, but we didn’t find such animals,” said Niu Yang (牛洋), of the Kunming Institute of Botany, and coauthor of the study in Current Biology. “Then we realized humans could be the reason.”
In the study by the Kunming Institute of Botany and the University of Exeter, researchers measured how closely plants from different populations matched their mountain environment and how easy they were to collect, and interviewed local people to estimate how much harvesting took place in each location.
In a computer experiment, people were found to take more time to discover the more camouflaged plants, suggesting that humans are driving the rapid evolution of this species into new color forms because better-camouflaged plants have a higher 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 every June. The bulb of the fritillary species has been used in traditional Chinese medicine for more than 2,000 years, but high prices in the past few years have led to increased harvesting.
“It’s remarkable to see how humans can have such a direct and dramatic impact on the coloration of wild organisms, not just on their survival, but on their evolution itself,” said Martin Stevens, of the Centre for Ecology and Conservation at the University of Exeter. “Many plants seem to use camouflage to hide from herbivores that may eat them — but here we see camouflage evolving in response to human collectors.”
“It’s possible that humans have driven evolution of defensive strategies in other plant species, but surprisingly little research has examined this,” he said.
Australian scientists have raised questions over the efficacy of the AstraZeneca and University of Oxford COVID-19 vaccine in establishing herd immunity, calling for a pause on its widespread rollout as the country recorded one new case of the virus yesterday. Opposition to the vaccine casts a cloud over Australia’s immunization plans, with 53 million doses of the AstraZeneca jab already on hand. “The question is really whether it is able to provide herd immunity. We are playing a long game here. We don’t know how long that will take,” Australian and New Zealand Society for Immunology president Stephen Turner said. Turner added
A racing pigeon has survived an extraordinary 13,000km Pacific Ocean crossing from the US to find a new home in Australia. Now authorities consider the bird a quarantine risk and plan to kill it. Kevin Celli-Bird yesterday said he discovered that the exhausted bird that arrived in his Melbourne backyard on Dec. 26 last year had disappeared from a race in the US state of Oregon on Oct. 29. Experts suspect the pigeon that Celli-Bird has named Joe — after US president-elect Joe Biden — hitched a ride on a cargo ship to cross the Pacific. Joe’s feat has attracted the attention
A persistent blizzard on Saturday blanketed large parts of Spain with an unusual amount of snow, killing at least four people and leaving thousands trapped in vehicles or at train stations and airports that suspended all services. The national weather agency reported that as of 7am, the snowfall in Madrid reached a level unseen in a half-century. More than 50cm of snow fell in the Spanish capital, the weather agency AEMET said. The bodies of a man and woman were recovered by the Andalucia region emergency service after their car was washed away by a flooded river near the town of Fuengirola.
China has recorded the biggest daily jump in COVID-19 cases in more than five months, despite four cities in lockdown, increased testing and other measures aimed at preventing another wave of infections in the world’s second-biggest economy. Most of the new infections were reported near the capital, Beijing, but a province in northeast China also saw a rise in new cases, official data showed yesterday, amid a resurgence that has seen more than 28 million people under home quarantine. The Chinese National Health Commission said in a statement that a total of 115 new confirmed cases were reported in the country, compared