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.
Ant species that have more than one queen in their nests are called polygyne. Colonies with only one egg-laying queen are known as monogyne. Queen ants and males are part of the reproductive castes. They are the most important members of a colony because they ensure the survival of their species.Queen ants, regardless of species, often are larger than other members of their colonies.Queen ants also have thicker bodies, making them easily distinguishable.The abdomens of queen ants are larger than those of other ants, and they possess wing muscles specific to their caste.ueen ants, regardless of species, often are larger than other members of their colonies. Queen ants also have thicker bodies, making them easily distinguishable. The abdomens of queen ants are larger than those of other ants, and they possess wing muscles specific to their caste.