Squid

Eden Rosenbloom

Description

Squid are in the mollusks classification, particularly Cephalopoda. This class is any mollusk that has a head which sticks out, a set of numerous arms or tentacles, and whose body is symmetrical. Squid follow all of these characteristics, and they specifically have 8 arms arranged in pairs and have 2 longer tentacles. There are over 300 species of squid, but the 2 most common are the giant squid and the colossal squid. A unique fact is that when they feel as though they are in danger, they release a dark colour of ink as they make a rapid escape, since they are strong swimmers. 

Habitat

Considering the fact that there are numerous species, the squid's habitat varies. Some live in a warm temperature, while others prefer chilly waters. They are found in almost every major body of water. However, they tend to prefer salt water since many aquatic animals are found there. The ocean is the only body of water that they giant squid is located in. Interestingly, squid are mainly found at the bottom of the ocean floor, making it difficult for them to be detected. 

Predator Adaptations 

Squid have a small beak like mouth that helps them kill their prey and shred it into smaller pieces, making it easier for them to consume. They use their tentacles to capture their prey. The sharp rings on the ends create a tight grip while using suction. Squid are carnivores. Depending on their size, a squid's appetite has a large variety. It ranges from animals as large as whales, to smaller creatures such as Plankton or shrimp.

Prey Adaptations

Squid are an excellent food source for birds, fish, and even sharks. However, their predators are based off of where they are situated in the world. For example, those who live in warmer regions have more predators than those that live in the cold. Also, if they live near the surface, they have a greater chance of being consumed by birds. Some species of squid have the ability to change their skin colour to match their surroundings, a great way to hide from their enemies. Some specific predators are the Blue-ring Octopus, sperm whales, tuna fish, and sharks.

Symbiosis

The hawaiian bobtail squid has a symbiotic relationship with luminescent bacteria. As they swim near the surface, they "glow", but they don't do this themselves. It is from the bacteria, living in their organs. This type of symbiosis is called commensalism, when one organism benefits and the other is unaffected.They glow due to a chemical in a family known as luciferins. Sometimes this happens to the Box Jellyfish as well.

Comparison- Blue-ring Octopus

Similarities

Squid and the blue-ring octopus have several things in common. They are both cephalopods with eight arms, and are head footed animals. They are blue blooded and have large varieties of habitats.

Differences

One difference is that they catch their food differently. While squid catch food with their long tentacles, octopi grab their prey, break through its shell, and inject paralyzing venom into it. Also, an octopus's life-span is 1-3 years, while a squid's ranges from 9 months-5 years.

Resources 

Squid. Photograph. Encyclopedia Britannica Image Quest. Web. 17 May 2013.http://quest.eb.com/images/118_808108

Clyde Roper. The Ocean Portal. May 20^th, 2013. May 20^th, 2013. http://ocean.si.edu/giant-squid

Infoqis Publishing, Co.May 20th, 2013 http://www.squid-world.com/

Cara Lea Council-Garcia. The University of New Mexico. 2002. May 21, 2013 http://biology.unm.edu/ccouncil/Biology_203/Summaries/Protostomes.htm

DiffEn. June 2, 2013. June 2, 2013.  http://www.diffen.com/difference/Octopus_vs_Squid