For Valentine's Day: Red is the "color of the deep"

In honor of Valentine's Day, today's post is dedicated to the color Red.  For humans, we often associate vibrant hues of red and pink with love and romance.  For deep sea fish and invertebrates, this same vibrant color is actually camouflage.  As light penetrates the surface of the ocean, the higher energy, longer wavelength red light is absorbed first.  That means that as you descend more than a few meters past the surface, all the red light is quickly absorbed.  With no red light present at depth, objects that are red in color appear drab and grey. 



Visible spectrum attenuation as a function of depth.
Taken from http://marineodyssey.co.uk/abioticoceans.html





For animals that live at extreme depths, red becomes the perfect color for avoiding visual detection.  Furthermore, deep sea animals have lost the ability to see the color red making red colored prey (or predators) even more difficult to detect.  The Monterey Bay Research Institute (MBARI) posted a video on YouTube that shows lots of different deep sea animals which are Red in color.  Check it out!

http://www.youtube.com/watch?v=16wZSHPvVGI&feature=youtu.be