Best Answer: The pupil size limits the the amount of light that enters the eye. There are also day-time photoreceptors, the cones, which occur with three kinds of photo-sensitive pigments, for red, yellow-green, and blue.
Those âdevotedâ dogs lying on their mastersâ graves? Theyâre depressed. âMany dogs are simply depressed for their whole lives because theyâre deprived of the normal amount of attention, exercise, and stimulation they need from day one. These humans wonât know they have a problem and wonât want the dog any livelier as that wouldnât fit in with their lifestyle,â says Tamara.
ADHD is in fact extremely rare in dogs. In most cases, a dog that appears to be hyperactive is actually bored, attention seeking or anxious. Many first (or even second) time owners donât realize that dogs are clever animals that need something to do with their brain, and a way to use up their often boundless energy.. Have a chat to your veterinarian to find out if your dog is suffering from anxiety. This isnât uncommon in pet dogs and if it is affecting your much loved canine buddy, then there are things you can do to help. Your vet may refer you to a specialist veterinary behaviorist for treatment.