What is the ratio of males to females on the planet?

For humans, the male to female ratio is slightly biased. This is influenced by a whole range of factors and changes as you move through the generations.

By Luis Villazon

Asked by: Jacob Hackett, Swadlincote

Males have slightly higher mortality rates for subtle genetic reasons as well as war and occupational hazards. To offset this, we have evolved a slight male bias of 110 boys born for every 100 girls. This gap gradually narrows as you move up through the age groups to reach a 1:1 ratio around reproductive age. The ratio of men then continues to fall to around 79:100 after age 65.

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Luis Villazon

Q&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.