When Kunta / Toby brings the infant Kizzy back inside from the naming ceremony, the back of the infant's head has thin, slick hair.
But in the next shot of the infant in the cradle, her hair is thick and curly.
Chicken George is Kizzie's son by her white master Tom Moore, yet is darker skinned than his mother. This is genetically impossible. *Not necessarily-a child can physically resemble either parent, or relatives from either side of their family, even one from previous generations.*
When Kunta holds baby Kizzy for the first time, Kunta's mouth is visible at the left edge of the screen. He speaks, but his mouth doesn't move.