Light in Aquatic Habitats
• Aquatic habits have altered light environments
• Water rapidly attenuates longer wavelengths
(red) of light
• Below 30 m, only blue wavelengths of light
• Below about 150 m, there is total absence of
• So what do you think happens to the coloring
of species are you get deeper and deeper? Organisms Making Their Own Light:
• Range of organisms can use chemical energy
to make light referred to as bioluminescence
Bio = living Lumen = Light
• Bioluminescent organisms use light to:
– Attract a mate
– Attract prey
– Communicate Bioluminescence
heard-of-bioluminescence.html IS THERE A DARK
SIDE OF LIGHT? The dark side of light?
• Light can damage biological molecules (including
DNA). What could happen if DNA is damaged?
How can this be repaired?
http://www.water.aero/disinfection.html The dark side of light
• How can we be protected from sun damage? Figure 2. Relationship of Skin Color to Latitude
Barsh GS, 2003 What Controls Variation in Human Skin Color?. PLoSBiol 1(1): e27.