The beginning of the use or writing marks the end of "prehistory" and the beginning of the "historical period." This transition was gradual and varied from place to place.
you can develop breasts before you begin your period. however it is more common to develop them after.
humans
No
because of a common ancestor of all vertebrates in Pre-Cambrian period, scientists says that they all will have a common development stage.
In the late period of the Cenozoic Era humans first existed.
Humans have an average gestation period (time of pregnancy) of 280 days.
Womb like humans
Humans have an average gestation period (time of pregnancy) of 280 days.
Latent period is the length of time that it takes for a disease to develop
Horses are like most mammals (humans, too) and the unborn develop in a uterus.
It depends what the animal is.