That Huge Eye

Big eyes can be associated with dog eyes… Mark Plonsky (professor and expert on animal behavior) has compared the average human’s and dog’s vision... Dogs are red-green color blind, which occurs in 4 % of male humans. This is due to having only two, not three, cone types – light sensitive cells in the retina include cones and rods. Since dogs have no area with 100 % cones, their eye for detail is roughly six times poorer than in an average human! However, dogs have much better night vision for two reasons. They have more rods and a reflective surface behind the retina, reflecting light back through it (giving that eerie shine at night). Dogs are also better able to detect movement. Due to the placement of the eyes.., humans have an overlap of the field of each eye of 140; in dogs, it is about 100. This results in the dog having limited ability to focus on items at different distances, but a wider overall field, allowing them to see more of the world!