Most behavioral biologists assume that animals do feel pain, grief and joy, but they do not express these emotions by shedding tears. They use different behaviors, like, many cats cry out loud when someone accidentally kicks their paw or tail.
Then, where did the expression CROCODILE TEARS come from? Mammals and reptiles have tear glands to keep their eyes moist. Logically speaking, they can shed tears.
Reflective and Emotional Tears
There are two types of tears we shed and both vary in their chemical composition. The first one is Reflective Tears. If a small particle gets into the eye, it is flushed out using tear fluid, this tear is called a reflective tear. It is pretty much released automatically to clean the eye. The tears that rolls out of our eyes, when we cut onions, also belong to this category.
Then, there are the emotional tears. Babies draw attention to themselves by crying. They have not yet mastered any other form of communication. Children and adults express different emotions such as loss, grief, insult, anger, and also joy with tears.
The emotional tears even have a slightly different chemical composition than the reflective tears. They contain more proteins, more minerals and an increased concentration of serotonin. This is a messenger substance in the brain that is released when there is pain, among other things. You can also differentiate tears chemically.
Crocodile Tears Are Caused By Pressure
What is behind the term Crocodile Tears? Crocodiles actually produce a secretion that runs out of their eyes when they eat. People initially assumed that the animals give the appearance of pity for their victims. The saying ‘crocodile tears’ is used when someone pretends to show compassion. However, the animals do not shed their tears based on emotion or reflex.
Rather, the tears have a mechanical cause. When the lizards open their mouths while eating, the upper jaw presses on a gland behind the third eyelid. This secretes a secretion that then rolls out of the eyes.
The same mechanism also works in humans. Bogorad’s syndrome is one such condition in humans where we shed tears while eating. We usually do it unconsciously but we essentially follow the same mechanism as crocodiles and that does not mean that we feel bad for the food we are eating. There is another way of replicating what happens to crocodiles. It is if you press lightly on the inner corner of your eye, tear fluid also comes out of your eyes.