Rare evidence of the long-held belief that humans are still evolving has been unearthed in the parish records of a French-Canadian island on the Saint Lawrence Seaway, researchers say.
Ile aux Coudres is located 80km northeast of Quebec City. Between 1720 and 1773, 30 families settled there and the population reached 1,585 people by the 1950s.
Poring over church registers containing detailed records of dates of births, marriages and deaths, researchers found the age of women when they had their first child fell from about 26 to 22 years over 140 years from 1799 to just before 1940.
After discounting environmental and social factors, they concluded this substantial change from one generation to the next “largely occurred at the genetic level.”
“It is often claimed that modern humans have stopped evolving because cultural and technological advancements have annihilated natural selection,” said the study led by Emmanuel Milot at the University of Quebec in Montreal.
“Our study supports the idea that humans are still evolving,” it said. “It also demonstrates that micro-evolution is detectable over just a few generations in humans.”
The age when women have their first child is a “highly heritable” trait.
The researchers point to reports of other insular pre-industrial societies showing that natural selection favored an earlier age for women to have their first child, allowing bigger families and often better health.
Ile aux Coudres’ population is very homogeneous, particularly in traits known to correlate with the timing of reproduction such as social class, education and religion.
This made it ideal for statistical analysis.
The study notes that the observed reproduction changes might be responses to improvements in nutrition, observed in the 19th and 20th centuries in Western societies.
“Better-fed women grow faster, mature earlier and in a better physiological state and are more fecund,” it said.
However, that would then have lead to “an increase in infant and juvenile survival rates,” whereas in fact over the 140 years those remained stable, the study said.
The researchers also dismissed the possibility that the trend was the result of genetic drift — the random sampling of genes between generations — as it was too strong to be random.
The study, “Evidence for evolution in response to natural selection in a contemporary human population,” is to be published in the next print issue of the journal The Proceedings of the National Academy of Sciences tomorrow.
FOX HUNT: To suppress dissent, Chinese living abroad that Xi Jinping sees as threats are told to either return to China or commit suicide, Christopher Wray said Chinese agents have been pursuing hundreds of Chinese nationals living in the US in an effort to force their return, as part of a global campaign against the country’s diaspora, known as Operation Fox Hunt, FBI Director Christopher Wray said on Tuesday. In a speech about the security threat posed by China, during which he said Beijing’s counterintelligence work was the “greatest long-term threat to our nation’s information and intellectual property, and to our economic vitality,” Wray gave the example of one Fox Hunt target who was given a choice of going back to China or killing themselves. Fox Hunt was launched
INTERNET CURBS: People are rushing to erase their digital footprints after police given powers over online activity, although it might take years for the full effect to be felt At midnight on Tuesday, the Great Firewall of China, the vast apparatus that limits the country’s Internet, appeared to descend on Hong Kong. Unveiling expanded police powers as part of contentious new national security legislation, the Hong Kong government enabled police to censor online speech, and force Internet service providers to hand over user information and shut down platforms. Many residents, already anxious since the legislation took effect last week, rushed to erase their digital footprint of any signs of dissent or support for the past year of protests. Hong Kong Legislator Charles Mok (莫乃光), a pro-democracy member of the Legislative
‘SUICIDE’: Media reports said Park Won-soon went missing on Thursday after a staff member filed a sexual harassment claim against him this week Seoul mayor Park Won-soon, viewed as a potential candidate for the 2022 presidential election, was found dead of an apparent suicide hours after he was reported missing, police said, adding that he was the subject of an undisclosed investigation. In a note he is thought to have left behind on his desk, Park offered his apologies. “I thank everyone who was with me in my life. I apologize to my family for only making them suffer from pain,” according to the note that was released by his office yesterday. Park, in his letter, asked to be cremated and have his remains spread
RISKY BUSINESS: The Chinese firm has stockpiled 500,000 pieces of 5G equipment not covered by US sanctions, but fears a wider ban could be announced in the UK Huawei Technologies Co believes it can supply 5G hardware unaffected by US sanctions to the UK for the next five years, sidestepping the expected conclusion of British emergency review on Tuesday. The company has stockpiled 500,000 pieces of kit, but fears a wider ban on its equipment is to be unveiled to placate rebel British Conservative Party lawmakers, who say that the Chinese supplier represents a national security risk. The British government on Friday said that it was “very likely” that British Secretary of State for Digital, Culture, Media and Sport Oliver Dowden would make a statement to parliament on Tuesday