Dogs do have nictitating membrane and a third eyelid.
The nictitating membrane is the third eyelid which is a triangular, mobile, protective glandular structure that is located between the lower eyelid and the cornea.
The majority of the third eyelids are hidden at the inside corner of the dogs eyes.
Even cats have nictitating membranes and third eyelids.
Dogs can see color although dogs can only see and discern the colors of yellow and blue as dogs only have two types of cones while humans have 3 types of cones that allow humans to identify combination of red, blue and green colors.
So dogs cannot see all colors that humans can but dogs do see some colors.
Dogs have what is called dichromatic vision.
Dogs can see in the dark as they have rod-dominated retinas that allow them to see well in the dark.
Although because their retinas' contain only about one-tenth the concentration of cones (that humans have), dogs do not see colors as humans do.
Dogs stare at you as a way to show affection to you and also because they may want to play with you or be petted.
Dogs may ignore you when you call them when they are distracted, confused or just not interested or they may just not understand that you're wanting them to come to them.
Dogs communicate volumes with their posture, their tails, their eyes, and their ears.
For this reason, their first instinct when trying to figure out what we want is to watch us; not to listen to us.
Dogs run away from their owners when they are scared, being abused, being mistreated, when they are bored or when they don't get enough exercise and have too much energy.
When dogs run when they are scared the dogs may sometimes run and hide under beds, behind couches, behind chairs, inside of bedding or the dog may run and hide under vehicles, in alleys, in bushes etc.
When it's raining stray dogs will seek shelter on cars, trucks, vehicles, neighbors porches, other shelter in parks etc.
Lost dogs do miss their owners and get sad when they are away from their owners.
Dogs that reunite with their owners after being lost are usually really excited to see their owners and family when they get back to them.
Dogs that get lost sometimes feel panicked and scared or terrified once they know they are lost.
Dogs are able to hone in on one specific smell (a familiar person, animal, pee marked tree) and follow it for long distances.
They rely on overlapping circles of familiar scents to find their way back home, much like we can rely on cell phone pings on towers to find specific locations.
A lost dog can usually survive without food for up to a week and sometimes a bit longer.
Some dogs may find some type of food when lost or find dead animals to eat.
The dogs that are most likely to run away are.
Catahoula Leopard Dog.
Pit Bull Mix.
Black and Tan Coonhound.
Dogs do know when they're lost although a dog may travel for miles before they realize they are lost.
When a dog is lost a dog can travel as far as 5 miles when lost if the dog is a healthy dog.
Smaller dogs may only travel as far as a mile or two but some have traveled the 5 miles.
Sometimes a dog may be picked up by someone thinking they were abandoned and then be taken across state lines.
A lost dog can sometimes survive for up to a week without food when lost although some dogs may get sick and weak by 2 days of having nothing to eat.
Some dogs go into survival mode almost immediately when separated from their owner.
Some do not go into survival mode for a week or more.
It depends on the dog, the dogs past experiences, the dogs breed, and the circumstances surrounding the dog being lost.
A dog can sometimes find it's way home.
Although not always the case it is possible for a dog to find it's way home and eventually come home.
If your dog goes missing at night try and search for the missing dog as long as you can.
Use a flashlight and look around and ask neighbors if they are around to see if they have seen a dog that went missing.
Also post on social media in your area about the missing dog and call up local shelters, call the non emergency police number or animal control and let them know about the missing dog.
In some cases a dog that is missing will return home the next day or a few days later.
Statistics indicate that most lost pets are recovered within 30 days.
But the time varies greatly depending on whether it is a cat or a dog.
Most people will notice a stray dog and even try to help it.
Lost cats are inclined to be furtive and they are harder to spot.
Dogs can sense death because dogs have a heightened sense of smell.
When death is near the dog can usually tell the death is coming or has come.
Dogs most often think all day about their owners, companions, food, toys, other dogs and wanting to play.
A dog can smell it's owner as far as 12 miles away as dogs have a very good sense of smell.
The closer you are the better they can smell you.
Dogs have a strong sense of smell so it is not really surprising that they can smell their owners as they are coming home.
Dogs know the smell of their owners very well.
Their scent lingers long after they leave home and gradually diminishes over the course of the day only to return back strongly when they arrive home.
Dogs do tend to get Jealous when they smell another dog on you.
Dogs can smell other dogs that have been on you and they may get Jealous as a result and the dog may sniff you and sense the other dog.
Signs of a dog being jealous include.
Getting between owner and other objects.
Behavior towards an object or thing you're interacting with.
Extra attention to you.
Psychologists performed a study on dog behavior and learned without a doubt that dogs do get jealous.
Whether it's jealousy as humans experience it, or an offshoot of deeply ingrained dog behavior like resource guarding or redirected excitement, dogs do feel envy.
To say sorry and apologize to your dog approach the dog calmly and talk to them calmly and simply say I'm sorry and pet them.
Even though they will not understand the sorry word they will understand that you're apologizing to them.
When you accidentally bump into your dog, they can most likely tell that it was not directed at them.
Should this happen frequently, he will get more careful when you move around and try to get out of your way sooner, but chances are, he will “forgive” you.
A dog can be mad at you.
Just like humans dogs can be mad at someone.
Signs that your dog is mad or angry at you or mad or angry in general include.
Stiff body posture.
Ears pinned back.
Bites of different intensity (from light snipping to puncturing bites)
When a dog huffs at you it's usually a sign of aggression, stress or anger in the dog or the dog wants to be left alone.
Although sometimes huffing in dogs is a way of expressing happiness and contentment.
Dogs do sometimes forget their owners but rarely does a dog forget their owners.
Dogs have very good memories and dogs have been known to recognize and remember their owners after being away from them for a few years.
Most dogs do not simply forget about their previous owners when adopted by new ones, at least not immediately.
The longer a dog lives with someone, the more attached they tend to become.
Some dogs may seem a bit depressed at first when suddenly uprooted from their familiar surroundings.
Dogs do not usually recognize themselves in the mirror as most dogs tend to bark at themselves in the mirror thinking the dog is another dog.
My own dog will bark at himself every time he gets in front of a mirror so he thinks the dog he sees is another dog like him and is confused.
Dogs can and do cry and the dog sometimes sheds tears when they cry as well.