The Glass Octopus – A Rare Sighting

The glass octopus is a rarely-spotted organism found in tropical and subtropical seas around the world. This organism gets its name due to its transparent body which looks like glass. One can look straight through its body to see the nerves, the eyes, and the digestive tract. Scientists believe that the glass octopus gained its transparent body through evolution in order to hide from predators in the ocean.


An adult glass octopus is around 45 centimetres (18 inches) in length. The glass octopus has eight tentacles or arms of varying sizes. The upper three pairs of arms are longer and have the same length. The fourth pair of arms is shorter in length. A row of suction cups or suckers are present on each of their arms. Scientists believe that the glass octopus mostly eats crustaceans, marine snails, small clams, and other mollusks. However, the glass octopus may also eat whichever food is available in deep sea regions.


The glass octopus is found in the mesopelagic and bathypelagic zones of the ocean. The mesopelagic zone ranges from 200 to 1,000 meters (~656 to 3,280 feet) below the ocean surface. The bathypelagic zone ranges from 1,000 to 4,000 meters (3,300 to 13,000 feet) below the ocean surface. Thus, the glass octopus roams in dark regions having less than 1% of sunlight.


The glass octopus is a member of a group of organisms known as the cephalopods. Cephalopods are mollusks that have arms attached directly to their heads, and includes octopuses, squid, and cuttlefish. Because the glass octopus roams in deep sea regions, scientists do not know much about this organism. In fact, it is one of the least studied cephalopods.


Information about the glass octopus has only been gained through a few sightings. Every time this organism is spotted, scientists understand this species better. For example, information about how the species responds to the changing ocean environment has been obtained. The gut contents of their predators have also revealed more information about these organisms.


Watch this video of a glass octopus moving through the deep sea of the Central Pacific Ocean!

Flesch Kincaid Grade Level: 8.1


Flesch Kincaid Reading Ease: 63

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