Sex ratio at birth

[Tomenable]

Number of males per each female at birth throughout the world ranges from 1,26 to 1,01 - depending on country:

https://en.wikipedia.org/wiki/List_of_countries_by_sex_ratio#Countries

Chromosome Y likely contains mutations which increase the share of males among offspring, but mtDNA or chromosome X probably contain mutations increasing the proportion of females. Autosomal DNA likely has mutations which block these attempts by Y and mt or X to proliferate themselves excessively. Y is winning this competition as we can see: everywhere in the world males are >50% of newborns.

Probably because in prehistory and most of history more males than females at birth = more potential warriors.

[JohnBravo]

More warriors means a war coming.
I was always amazed how animal population is somehow controlled by its genetics, low population = more females are born, large territorial population more males are born, however as far as I know predators are still required to correct if the above is insufficient e.g. against species like deer, antelope etc.
How about gender control by timing of the conception, depending if it happens shortly before or after female's period?

By the way have you tracked source of your R1b? Is it French, Iberian or Celtic?

[Tolan]

Yes, but the difference is compensated by a higher infant mortality rate among male.
(difficult birth, more premature, young boys are more vulnerable than young girls ect ...)

This is particularly visible in my family tree.
In the period 1675 - 1750:
I have the birth of 525 boys and 484 girls (ratio 108)
but I have 103 deaths of boys under 5 years for only 69 girls
(Ratio 149)
Consequence: there are more woomen in adulthood than man!

Infant mortality don' have much of an impact today, but it was very important in the past

[JohnBravo]

So the straight explanation is that these days we heal (male) infants to let them die on the battlefield in bigger numbers since nothing but only mankind can control the population. I mean XX century has showed the biggest war death tolls ever.