Accommodation is primarily achieved by the '''lens''', which is stretched by rectus muscle fibres of the ciliary body, causing the optical power of the eye to increase. This allows the eye to maintain a clear focus on an object, especially as the animal moves nearer towards the object. | Accommodation is primarily achieved by the '''lens''', which is stretched by rectus muscle fibres of the ciliary body, causing the optical power of the eye to increase. This allows the eye to maintain a clear focus on an object, especially as the animal moves nearer towards the object. |