By Marianne White
QUEBEC — The first settlers to colonize the wilderness of northeastern Quebec had more offspring and were more successful in passing on their genes than those who followed, according to a genealogical research published Thursday in the journal Science.
The study, conducted by Canadian and Swiss researchers, looked at the genealogy of more than 1.2 million Canadians in the recently colonized Quebec regions of Charlevoix and Saguenay-Lac St. Jean.
The researchers believe their work offers a rare look at how populations and genes spread during rapid territorial and demographic expansions.
“We hope that our results can lead to a more general observation about human evolution,” said Damian Labuda of the University of Montreal and Sainte-Justine Hospital.
He also noted very few studies have explored the consequences of human expansions in the past 50,000 years.
The academics found the first wave of European settlers, who migrated to those regions as of 1686, had 15% more children than people who came later or those who stayed in established colonies.
Those first settlers also had 20% more children who married, which is a selective advantage, according to the researchers.
“They had a greater reproductive success and could much better transmit their genetic imprint,” said one of the authors, Laurent Excoffier, of the University of Berne and Swiss Institute of Bioinformatics.
He noted the higher fertility rate could be related to the fact that women living in new settlements married, on average, one year earlier than those who settled into central towns.
The researchers referred to the pioneers on the edge of the colonization wave as being on the ‘wave front’ — as they were the first to settle in an otherwise uninhabited region. They used a database of the descending lineages of the 88,000 marriages in the two Quebec regions from 1686 to 1960.
“We followed this moving front for about three centuries,” Excoffier said.
Through parish records, they tracked down more than 1.2 million descendants and found more than 80% of the people currently living in the Saguenay region are related to ancestors who lived on the wave front of colonization, or only one generation away from the wave front.
Excoffier noted that although it is difficult to generalize their findings, it is likely that a considerable fraction of human ancestors lived on the wave front considering the successful colonization of the planet.
Helene Vezina, of the Universite du Quebec in Chicoutimi, along with research associates Claudia Moreau, Michele Jomphe and Ph.D. student Claude Bherer also contributed to the research.