In light of our recent eye dissection and my curious observation of ClearEyes, I wondered, what makes up tears?
Apparently it is one part water, one part oil and one part mucus. The mucus helps to keep the cornea lubricated. The oil helps the tears from evaporating. The water part is the most interesting. It is a sexy salt (saline) solution that contains many vitamins, minerals, and antibiotics.
The function of tears is to keep our eyes moist and bacteria-free.
We are constantly producing tears throughout the day which are released from our lacrimal glands and drain into our nasal cavity. When we release too much, they flow over our eyes and we notice it as crying.
Now the physiological/evolutionary purpose of crying when we are upset is, from my knowledge, unknown….but it would be interesting to hear everyone’s theories!
tears....to release frustration, hurt, pain...as well as happiness and relief.
ReplyDeleteyes but what is the evolutionary purpose for crying?
ReplyDeleteHow did/does crying make us better fit for survival?
I believe it came from babies trying to let their moms know they are hungry (i.e. it's time for them to be breast fed again)
ReplyDeleteis that the actual crying or the sound/wail of crying?
ReplyDeleteDon't tears also release something that makes you tired? You cry when you're injured which makes you tired so that you will sleep and allows you to heal better?
ReplyDeleteOooh interesting...I've never heard that one! From an evolutionary perspective, that makes tons of sense!
ReplyDelete