Known as the Argonaut, this male mollusc has a very sacrificial way of impregnating their female counterparts. The male has one arm longer than his others, known as a hectocotylus, which is used to transfer sperm to the female. The arm stores up the sperm, and when the male finds a female he wants to mate with, he will detach the arm during the mating process. Specifically, once the “arm” finds the pallial cavity of the female, it gets inserted. A “Funnel-mantle locking apparatus,” basically a Chinese finger torture device for the octopus, then keeps the arm from escaping.
The female will store the hectocotylus in her cavity. Unfortunately for this sea-faring Casanova, the male is only able to copulate once. The female, however, is capable of mating several times over her lifespan. In fact, females have been found that have several hectocotylus in their pallial cavity at the same time! (Eat your heart out Traci Lords!)
Female Argonauts are not in danger of a male liberal movement anytime soon. Fully grown females are only about 8 inches in length and the males are only around 1 inch. Further, the males are typically around 600 times lighter than the females! There is also the problem of lifespan. Males die shortly after mating and the females move on and forget about the sacrifice. Because of this, the females usually live for much longer periods of time than the males.
Just when you think the male persecution by their ferocious female flames couldn’t get any worse, until recently, it was thought that the hectocotylus found inside the females were tiny parasitic worms, rather than the penis of a male. These male octopuses could always use the classic “I was in a pool!” excuse, I suppose, as they do live in cold water!
- Female Argonauts are quite unique in the world of molluscs. They have the ability to make a thin shell called a “paper nautilus” made of calcium carbonate. They excrete this shell from two web-like structures on the side of the their body. It gets secreted as a horn that allows the female to encase their eggs. Due to its length generally being longer then the female herself, she can sometimes recede completely back into the horn.
- The shell made by female Argonauts was once thought to be where she lived, and the web-like structures could be raised as sails that allowed them to move across the ocean. This idea has been around for over 2,000 years when Aristotle began puzzling over the shells of these amazing little creatures. Recently it has been shown that the Argonauts actually use their shell to control movement by a much more ingenious method. The female will take air at the sea surface by rotating the shell counter-clockwise. The funnel seals off an air pocket in the top of the shell. The Female will then dive to a depth of about half a mile below the surface. Once there, she maintains the air pocket allowing her to be neutrally buoyant. This buoyancy has several benefits. It keeps her in a safe position in mid-water to avoid surface waves and many predators from above; it allows her to avoid any trauma from the sea floor that might harm the egg sacs during reproduction; and finally allows her to expend only a fraction of the energy other cephalopods use to maintain their positions in the water.
- Made up of mainly cartilage, there are 8 “funnel-locking mechanisms” used by cephalopods. They are named based on the shape of the locking mechanism itself. They are: lazy t-shape, inverted t-shape, straight shape, triangular shape, oval shape, oval with tragus/antitragus, boomerang shape, and keyhole shape.
- The common octopus ranges in size from about 12 inches to 36 inches. They weigh anywhere from 6-22 pounds and generally lives only about a year or two in the wild.
- The Giant Octopus, “Enteroctopus dofleini,” is much more frightening. It can range in size from 10-16 feet and weigh up to 110 pounds. Found mainly in the Pacific Ocean, they can live up to 5 years in the wild. They are also extremely intelligent, learning to do such things as opening jars, solving mazes and mimicking other animals.
- The appendages of octopuses are commonly mistaken as tentacles. They are actually called arms.
- The Argonaut was named in ancient Greece after the mythical ship “Argo”. This was the ship in the Greek myth “Jason and the Argonauts,” that tells the tale of a search for the famous Golden Fleece. It is thought that they chose to name this particular octopus after the ship due to thinking this mollusc used its shell as a boat and its arms as oars and sails (Aristotle once championed this theory as to what their shells were used for).
- In the Bronze Age, it was thought a fleece symbolized prosperity for those in possession of it, thus, fleeces were hung to renew royal power.
- The small island of Lemnos was the first stop of Jason and his Argonauts. Legend has it that this Greek island was inhabited by only women. Don’t think that this would be the ultimate spring-break getaway for college guys. All the women on the island murdered their husbands after being cursed by Aphrodite.
- When Jason encounters King Aietes, he asks him to return the Golden Fleece. The king states he will if Jason can perform a series of extraordinary tasks. Aphrodite, the goddess of love, makes the king’s daughter Medea fall in love with Jason. Medea then offers to help Jason complete the tasks if he will marry her. He agrees and completes the tasks put forth by the king. After completing the feat, the King organizes a banquet at which he tells Medea that he is going to kill Jason and his Argonauts instead of giving him the Golden Fleece. Medea betrays her father and tells Jason. She then helps him get the fleece and he and the Argonauts flee for home.
- The three tasks that King Aietes asks Jason to perform are to harness fire-breathing bulls, overcome phantom warriors, and to plow a field with dragon’s teeth.
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