The tag has no wiki summary.

learn more… | top users | synonyms

6
votes
1answer
112 views

Does knowing the sex of each of a couple’s first N children have any marginal value in predicting the sex of child N+1?

Does knowing the sex of each of a couple’s first N children have any marginal value in predicting the sex of child N+1? By “marginal” I mean predictive power beyond other known effects, e.g., the race ...
3
votes
2answers
262 views

How can sex ratios remain Fisherian (1:1) in species where only the dominant male gets to mate

In certain species only the dominant male gets to mate (or given strong preference), and yet the sex ratio remains 1:1. (I'm thinking in particular of gorillas). How does this happen? It doesn't seem ...
1
vote
1answer
873 views

In what animal species is the sex ratio skewed in favour of the fertile female?

Ants have something like a single fertile female to several males. The same applies to bees, and larger animals - elephants too. Is the sex ratio universally skewed in favour of the female? What ...
14
votes
3answers
360 views

Are human fetuses more likely to be male?

Question: From a physiological point of view, when sex is determined in a human fetus, is it equally likely to be male or female? Studies in this area typically measure age at birth, where the data ...