The BVD stands for Back Vertex Distance, this is a measurement that is included on any prescription where the sphere or cylinder powers are higher than + or - 5.00D and to a lesser extent some prescriptions where it is less than this power.
Winged Drone | Alate | Male Ant. Drones are the only male ants in a colony. They are born from un-fertilized eggs. Drones are not like typical ants. They donât do any work in their nests, and they look more like wasps than ants. They are reproductive winged ants and so are alates.
There are three kinds of ants in a colony: The queen, the female workers, and males. The queen and the males have wings, while the workers donât have wings. The queen is the only ant that can lay eggs. The male antâs job is to mate with future queen ants and they do not live very long afterwards.Once the queen grows to adulthood, she spends the rest of her life laying eggs! Depending on the species, a colony may have one queen or many queens.he queen is the only ant that can lay eggs. The male antâs job is to mate with future queen ants and they do not live very long afterwards. Once the queen grows to adulthood, she spends the rest of her life laying eggs! Depending on the species, a colony may have one queen or many queens.