The stake is especially high in female mammals that bear their young and then care for the offspring after birth.
The males are said to be 'in rut' while female mammals are 'on heat'.
Most female mammals, including human females, have two X chromosomes.
The breast in male and female mammals is made the same way.
Individual male and female mammals meet and carry out copulation.
Pregnancy is when a female mammal has an unborn baby inside her.
The largest part of this book is devoted to female mammals, especially primates.