Some animals can cry

Why do we actually shed tears?

Some people have built close to the water, the smallest occasion is enough, and off you go: the tears seem to pour inexorably down your face, sometimes until your eyes are red. Everyone has their own way of crying, sometimes accompanied by sobs, short, violent breathing noises, sometimes very quietly.

The stuff that tears are made of

It is the lacrimal gland that creates the fluid. It sits between the eyeball and eyelid. The tear falls over the eye like a film. If there is too much liquid at some point, the barrel overflows, then the tears roll down - from the eyes, down the cheeks, sometimes even over the chin - no matter what the real reason for the cascade is.

The main component of tears is simply water. Proteins, enzymes and substances that contain nitrogen are added. Nine percent of tears are made of salt, and that's how they taste: Tears always taste salty. But there are different compositions - depending on whether we cry out of grief or heartache or shed tears of joy.

Basal tears

Our body produces tears not only when we cry, but permanently. If it weren't for that, our eyes would dry out. Many people know that. Often the air in the rooms in which we are staying is very dry. The tear glands ensure that the eye is kept moist. The tear fluid protects our eyes from small foreign bodies, flushes them out of the eye and the regular blinking of an eye works like a windshield wiper. The secretion contains germicidal substances, among other things. These tears are called basal tears. So we don't just need tear fluid to let our emotions run free.

When you cut onions, tears come to you

Reflex tears

Actors reportedly put an onion under their noses before having to play a very sad scene of crying. The scientific explanation is rather sober, however: In a freshly sliced ​​onion, an enzyme releases a sulphurous amino acid that gets the tears rolling.

There are plenty of tips to avoid shedding tears while chopping onions: For example, put on diving goggles, cut the onions under water, make a draft in the kitchen or ask a contact lens wearer to take care of the biting work. The contact lens acts as a kind of barrier and prevents the irritant from reaching the cornea of ​​the eye in the first place.

Most of us cry when we grieve

Emotional tears

Tears of sadness or joy are the best known for us. Part of the brain is responsible for emotions. This is the limbic system, especially the hypothalamus. The limbic system is connected to the autonomic nervous system, which we cannot control or regulate. The emotions trigger a stimulus to this nervous system, which in turn activates the area that produces tears.

Tears of feeling arise when strong emotions stimulate the autonomic nervous system. These emotional tears contain far more protein than reflex tears, for example. Science is also concerned with tears. According to a study by a German institute for ophthalmology, the flow of tears in women takes about six minutes. In men, it only takes about two to four minutes for a tearful period to pass.

Tears under the microscope 

The American photographer Rose-Lynn Fisher photographed tears under the light microscope and found that tears differ in appearance - depending on what the reason for our excessive tear flow is. Loss, relief, joy or the tears that roll down our faces while chopping onions - every tear looks different under the microscope. Below that, the structure is enlarged 100 to 400 times.

  • Not all tears are created equal

    Sadness and gratitude

    This picture is somewhat reminiscent of a map. Or an aerial view from high above the earth. But actually this is a tear - a tear of sadness and gratitude. It is estimated that every person produces an average of 80 to 100 liters of tears in their life. One maybe a little more, the other a little less.

  • Not all tears are created equal

    hope

    American photographer Rose-Lynn Fisher wondered in 2008 whether a tear of sadness would look like a tear of joy. She took a few tears and photographed them on a glass plate under the light microscope - and sure enough! At a magnification of up to 400 times it was obvious: tears differ in their appearance. Here is a tear of hope.

  • Not all tears are created equal

    Topography of tears

    From then on, Rose-Lynn began capturing tears - mostly her own -, dating and drying them, photographing them, and naming them. She has looked at over 1,000 pictures since then, she says. The recordings told such beautiful stories that an entire illustrated book with a wide variety of tear landscapes was created from them: "The Topography of Tears".

  • Not all tears are created equal

    Protection order

    Viewed soberly, the tear fluid simply protects our eyes from dust and dirt, for example. A sophisticated chemical cocktail ensures cleanliness. Our eyes are constantly forming basal tears so that they stay moist and healthy.

  • Not all tears are created equal

    compassion

    Tear fluid consists of three layers: The slightly slimy mucin layer lies on the cornea of ​​the eye. Above that lies the middle layer, which consists of 98 percent water. The outermost lipid layer is fatty and stabilizes the tear film. Here is a tear of compassion from Rose-Lynn's photo series.

  • Not all tears are created equal

    Repentance

    Tears contain water, salts, proteins, enzymes, and fat. But depending on the reason why we cry - a tear of repentance is shown here - the composition of the tear fluid differs.

  • Not all tears are created equal

    Onion tears

    In addition to basal tears, there are also reflex tears. They are caused by foreign bodies or environmental stimuli, for example by a grain of sand or by cutting onions (here in the picture). Sulfur-containing amino acids irritate the eye with a freshly sliced ​​onion. Reflex tears help flush out troublemakers. With them, therefore, the proportion of water predominates.

  • Not all tears are created equal

    Exhausted and drained

    And then there are the emotional tears. They arise when strong feelings stimulate the autonomic nervous system. Tears of exhaustion can be seen here. Such emotional tears contain up to a quarter more proteins than reflex tears, but less fluid.

  • Not all tears are created equal

    In the end it didn't matter

    Rose-Lynn cried the tear titled "In the end it didn't matter" at a moment when she didn't care. Where she was frustrated and unfulfilled. She took the tear and put a date on the slide. Then it was forgotten. When Rose-Lynn found the tear again and her frustration had subsided, one of the most beautiful tearscapes was revealed under the microscope.

  • Not all tears are created equal

    Making amends

    During her work, Rose-Lynn realized something else: A tear is never the same as a tear. Because even tears caused by the same emotion are different. There are many variables that influence the resulting image: the volume of the tear fluid, the evaporation or flow, the finest biological variations, the microscope and camera settings.

    Author: Hannah Fuchs


Can animals cry?

Science is still divided on whether an animal can cry, i.e. is able to express feelings. Some researchers believe that animals are quite capable of showing emotions. These scientists are convinced that mourning elephants, for example, shed tears, for example when a conspecific has died.

Do elephants really cry?

Most scientists argue that only humans are able to cry. But: there are actually crocodile tears. However, the animals do not cry because emotions overwhelm them. The explanation is rather sober: crocodiles have a third eyelid, in which a particularly large amount of secretion accumulates and which accordingly emerges again. If a person cries crocodile tears, it is just hypocrisy, so tears can definitely lie.

  • Mourning rituals in the animal kingdom

    Inseparable

    Gorilla mama Gana at the Münster zoo simply couldn't accept the death of her baby Claudio: for days she carried the lifeless body with her and defended it against the zoo keepers. Not unusual for great ape mothers: some do not part for weeks from the - now mummified - corpse of the deceased offspring.

  • Mourning rituals in the animal kingdom

    Burial at sea

    Orcas, dolphins and other marine mammals also carry their deceased cubs with them for a while - not an easy task in the water. Researchers observed mothers trying to balance their bodies on their snouts. When the dead bodies sank, the mothers dived after them. Even when adult dolphins die, the companions guard the dead body for days.

  • Mourning rituals in the animal kingdom

    Wake

    Elephants are known for their good memories - no wonder that they mourn their dead particularly intensely and for a long time. If an elephant dies, the other elephants in the group keep vigil over the corpse. Even elephants from neighboring groups come by and visit the deceased conspecific one last time.

  • Mourning rituals in the animal kingdom

    Grooming as a consolation

    Baboons show strong symptoms of stress when a companion they are familiar with dies. Your blood stress hormones rise, researchers have shown. In order to deal with a loss, they seek closeness to other baboons and dedicate themselves particularly intensively to grooming.

  • Mourning rituals in the animal kingdom

    Call for goodbye

    When corvids discover a dead conspecific, they summon other conspecifics. Together they then gather around the carcass. They also stop eating for a while. Above all, bird species that spend their entire life with a partner - geese and many songbirds, for example - mourn a lot. This can go so far that they no longer eat anything and die themselves.

  • Mourning rituals in the animal kingdom

    And what about fish?

    Fish often behave unusually calm when a conspecific dies in the same aquarium. But that's probably due to the stress hormones that the dying fish releases into the water, researchers say. Little research has been done to date on whether fish can actually mourn. But it is at least obvious for fish living in pairs - for example for the French angelfish.

  • Mourning rituals in the animal kingdom

    Pussy and mouse

    One can also mourn a companion who belongs to a different species of animal. This was shown by the cat Muschi and the collar bear Mäuschen in the Berlin zoo. The two had become friends. When the she-bear died, the cat refused to leave the bear enclosure and did not stop mewing.

  • Mourning rituals in the animal kingdom

    Guard at the grave

    A person who loses his beloved dog is terribly sad. The same goes for a dog who loses his beloved master. The German shepherd Capitan guarded the grave of his master in the cemetery of Villa Carlos Paz in Argentina for many years.

    Author: Brigitte Osterath