For some people, human evolution is still difficult to imagine but researches have sighted a phenomenon which seems to reflect evolution in a Canadian town. From 1800 and 1940, Quebec mothers in Ile aux Coudres have been observed to give birth at relatively younger ages, with the maternity age dropping from age 26 to 22, emphasizing increased fertility and larger families.
This phenomenon seems to be of biological evolution and not of changing cultural or environmental influences. University of Quebec’s geneticist Emmanuel Milot had said that this event is actually contrary to what has been considered as the fate of human evolution. He mentioned that cultural and technological advancements have been said to have stopped human evolution due to annihilated natural selection. Another aspect implied is that the changes, which are microevolution in essence, are detectable in only a few generations.
Human evolution today is considered to be a marvellous concern especially because biological evolutionary pressures have been assumed to begin to slow down. But there are really genetic signals observed now that give reason to think that evolution, instead of going down is speeding up.
The bases for such thoughts are on Milot’s study on the details of birth, marriage and death records in Coudres Catholic churches, and the conclusions are not only largely dependent on the fact that the average age of the first birth has dropped but also on the pattern of how the ages have dropped. These patterns fit models for gene-influenced natural selection. Other reasons like better nutrition were discounted because other aspects like infant and juvenile mortality should have followed the pattern too but they have not.
Harpending has said that Milot’s observations are part of a trend that points to changes that are not environmentally caused but genetically driven. Everywhere, studies are beginning to discover genetic changes. Milot further contended that although cultural and environmental changes have dominated changes in the world, and have shaped the selection pressures that act on women’s reproductive history, natural selection should not be dismissed because genetic influences are said to account 30 and 50 percent of age of first birth influences even if 50 to 70 percent is due the social factors.