October 15, 2020: Comb Jelly
Image courtesy of the NOAA Office of Ocean Exploration and Research, Gulf of Mexico 2018. Download larger version (jpg, 721 KB).
When caught in the light of a remotely operated vehicle like our Deep Discoverer, comb jellies (ctenophores) put on dazzling rainbow-hued light shows. Sometimes mistaken for bioluminescence, these colorful displays result when light is scattered by the moving rows of combs, or cilia, the animal uses to propel itself through the water.
This ctenophore was seen swimming just above the seafloor during a Gulf of Mexico 2018 dive. In the image, the ctenophore’s mouth is oriented upwards. The bright white lines at the base of the animal are the tops of the comb rows; they converge on an organ that helps to detect the orientation of the animal...so it knows which way is up (or down)!