Why pioneers bred like rabbits...

A new study out of Canada has used data from church birth and death records and identified that the pioneers had more children and those children contributed more genes to the modern gene pool than those that came after them.
   

Families that colonized the Canadian frontier contributed more genetic material to the modern population than folks who stayed home, says a new study...According to new research, the desire to expand into new territory may have provided an evolutionary advantage to those who had it over those who lacked it.

The article also compares the pioneers of the Canadian frontier to the plants and animals that colonize new habitats.

What do you think of the research? What do you think of conclusions and comparisons. Is there a genetic component to fertility as is suggested in the article?