By about week 10. http://www.babycenter.com/6_your-pregnancy-10-weeks_1099.bc?intcmp=timeline
In brief, yes they do. yes, as a mater of fact they do have fingernails when they are born
Smoking can cause yellow fingernails due to the chemicals in cigarettes staining the nails over time.
Some premature babies get dark colored or black fingernails because of the lack of fat under the skin which causes the skin to discolor. This can also be due to a lowered amount of oxygen in the extremities shortly after birth.
A baby developes fingernails while still in the mother's whombccccccccccccccccccccccccc
Uterus
Babies' tear ducts fully develop by the time they are about 12 months old.
Babies typically develop neck control around 2 to 4 months of age.
Babies are born with finger nails. And you can cut them right away, it is a myth that you need to wait.
Babies typically develop self-recognition in the mirror around 18 to 24 months of age.
My guess is that when the baby starts clawing at your insides, that you will become aware of the existence of its fingernails.
yes the reptiles develop in eggs