Unlike humans, most mammals and other animals possess dichromatic vision. This means that while humans see the world in shades of red, green, and blue, many organisms see only shades of blue and green. Dogs, cats, mice, and even deer cannot distinguish red from green - that's why a dog might lose their red toy in the green grass, or the deer won't see a hunter in the tall grass with a bright orange vest on. They aren't clueless, they just literally cannot distinguish the colors. 

Humans as well as other related apes like chimpanzees see color on a trichromatic range, allowing us to differentiate between many different colors. We, however, do not possess the best color vision. Birds and reptiles as well as some fish have tetrachromacy, letting them see in four base colors, and pick up on things that may be invisible to humans. This extends the range of visible light they can process and allows them more distinction between some of what humans call infrared and ultraviolet.

The bodies of plants and animals are shaped through years of evolution based on what traits are passed onto the next generation the most through reproduction. Some animals have developed into predators who hunt and kill other animals for their food and can fight other animals. Others have become herbivores and prey animals, who graze plants and flee threats. The niches animals fill in their ecosystem have developed how they live, and how their eyes work.

  The vast majority of prey animals have their eyes situated on the sides of their head, giving them a large view of their surroundings but limited depth perception. Predators conversely usually have their eyes facing forward, lessening their field of view but greatly improving their depth perception abilities. Depth perception comes from the eyes registering images from multiple angles and the brain using this to figure out how far an image is from it. The vision coming from one eye is deemed monocular vision, while the overlapping field is dubbed binocular vision.

While not actually vision, which is the reception of light, echolocation can give an organism just as much information about its surroundings as vision can. Echolocation, also called bio-sonar (yes, sonar is just man-made echolocation!) is the process of emitting sounds and determining what is around based on the echoes coming back from these sounds. From this, animals using echolocation can discern if anything is around them, where it is, how far it is away, and how big it is. Animals like bats, whales, dolphins, possibly hedgehogs, and some blind humans utilize echolocation. 

Bats make short and high-pitched squeaks, which are such high frequencies that humans usually can't hear them, and so loud the bats could deafen themselves if they didn't "shut off" their ears automatically while making these squeaks. Doing this, a bat can find insects in the dark up to ~20ft away and tell how big they are. Bats are so good at this that they can detect and avoid super thin wires in the dark without issue.

Dolphins and whales also use high-pitched clicks to echolocate. These sounds however are not made in the voicebox, but by forcing air through their nose into specialized air sacs under the blowhole. These soundwaves then pass forward into the melon, which is a large specialized mass of fat on the dolphin's forehead that highly focuses the direction of all the clicks into a "beam." If the call hits something, it echoes off the object and toward the dolphin, where the soundwave is picked up by the lower jaw and travels to the inner ears. This system is so sensitive that dolphins could find a golf ball in the dark water up to 400 feet away using just echolocation.