CREPUSCULAR

 Crepuscular is one of my favorite fancy words.  It came to mind the other day during the eclipse.  I've written about the vision of crepuscular creatures before.  These are many of the animals that live in the woods or forest.  Many animals, and insects for that matter, are seen mostly at dawn and dusk.  Crepuscular means twilight.  A lot of animals are only active in low light situations.

Deer and rabbits come to mind.  I think bear are the same way.  Why do they prefer the twilight?  It's because their eyes don't function like, or as well as, ours.  The pupils of their eyes don't close down, or close down very little, when it is very bright out.  They can't function well like that.  You've heard of a stunned person looking like a deer frozen in a car's headlights.  They can't handle the bright lights.  

The pupils of our eyes close or open to control the amount of light coming in.  During the time of darkness, during the total eclipse, the pupil of your eyes was very large - sensing the need to let in more light.  When you look at the sun, the pupil gets very small to protect you and your optic nerve from the extreme light. We are not crepuscular.   

The size of our pupils can be a tell-tale sign of other things besides light.  Most notably, opiates effect the pupil adversely.  Opiate users have very small pupil openings even when it is very dark.  The eye is trying to protect the person needlessly.  It is dangerous.  Even marijuana can cause the pupils to constrict somewhat.  The darkness is soothing and could be a sleep aid but it can be dangerous to drive a vehicle or perform other dangerous tasks. 

So, no cocaine or heroin for you the next time we have a solar eclipse.  Be safe.