Three theories of
why humans cry
Humans are the only ones to cry – no other animals cry when they
are sad. So, scientists have several theories considering why we cry.CRYING IS A RELIC FROM
OUR TIME IN WATER
In 1960, an English marine
biologist suggested that humans
descend from an aquatic monkey.
So, people believed that tears were
a remain from our ancestors.CRAZY
CRYING WARNS
OUR SURROUNDINGS
The tears which we cry when we
are sad include more protein than
the tears which cleanse our eyes.
According to some scientists, the
protein content changes the
consistency of the tears, so they will
roll slowly down the cheeks and be
seen by more individuals as a social
signal that we need attention.SOCIAL
CRYING IS THE
BODY'S WAY OF
REDUCING STRESS
Emotional tears include a natural
pain-relieving and sedative
substance - enkephalin. So, one of
the most established theories
involves that the evolutionary aim of
crying is to relieve the body of stress.NEW
after they are collected. In this way, he believes it is
possible to store tears of all categories without their
proteins, enzymes, and peptides breaking down each other.
The scientists from Tel Aviv plan to publish a scientific
article about the ground-breaking freezing method.
COMPUTER DISPLAYS ALTER CHEMISTRY
The plans of a tear bank have attracted international
attention, because many scientists have only just realised
the possibilities. Tear research could reveal how the
increasing use of smartphone, computer, and tablet
displays affects our eyes and the thin membrane of basal
tears which always covers them. The membrane ensures a
perfect optical surface for our vision and is maintained
every time we blink.
Generally, we blink less, when we are looking at a
display, so the protective tear membrane evaporates
faster. Hence, more people develop dry eyes and diseases,
by which the tear gland produces too few tears or too little
oil. The diseases mean increased risk of eye infection,
blurred vision, and sore, tired eyes. Studies have previously
indicated that our basal tears also change to include less
MUC5AC protein, when we spend a lot of time in front of a
display. The protein is an important element of the thin,
protective tear membrane. If Noam Sobel’s tear bank could
deliver tears from programmers, who spend most of their
time in front of a display, and from athletes, who rarely look
at one, scientists could compare their lachrymal fluids and
identify how the MUC5AC protein changes and whether
they can ease severe eye diseasaes by treating it.
Recently, scientists have also realized that
tears include biomarkers – materials which can
reveal severe illness, before it breaks out.
The quantity of the lacryglobin protein in
tears increases very early in the process
in people with breast and prostate
cancer. So, scientists hope to be
able to spot severe cancer, before
it becomes fatal, by analysing
patients’ tears instead of their
blood. Hopefully, the tear bank
will be full of donor tears at that
point. Until then: don't dry
your eyes.
SHUTTERSTOCK
Babies cry to get in contact
with other people.SHUTTERSTOCK