Argonaut (animal)
Paper boat ( Argonauta )
- Large paper boat ( Argonauta argo )
- Argonauta boettgeri
- Argonauta cornuta
- Winged paper boat ( Argonauta hians )
- Argonauta nouryi
- Pacific Paper Boat ( Argonauta pacifica )
Paper boats or argonauts ( Argonauta spp.) Are among the cephalopods ( cephalopods ) and here in the kinship group of the eight-armed squid.
They can be found as pelagic residents in all oceans, but are apparently quite rare. Nevertheless, it sometimes happens that large collections of animals are observed, especially off the Australian coast. This is especially the approximately 10 cm females, the males are, however, with only 2 cm is very small ( dwarf males ). Argonauts feed on small jellyfish and small crustaceans, they are eaten by larger fish.
The nautilus (Nautilus ) are the only extant cephalopods with a solid, calcareous outer casing. Paper boats have apparently also a calcareous outer casing. Younger relatives of octopuses (like this they only have eight arms ), however, do not have a real case, because this has been completely re-formed in the course of evolution. It was thought previously that the thin, white body of the paper boats are containers for the eggs of animals. Fittingly, they are created only by the adult female. However, recent studies indicate that the cabinet are provided for the storage of air to balance out the animal in the deep sea. The females swim to the surface and take a defined amount of air. This air is trapped in the body and the animal swims in the depths. Due to the growing pressure, the air bubble is reduced until the buoyancy sufficient to be weightless in the water. For the production of the cabinet are glands on the upper arms that produce a corresponding secretion. The females carry this case with you then. The housing can be up to 45 cm long about the Great Paper Boat ( Argonauta argo ). When Nautilus ( Nautilus), the housing consists of Kalkmodifikation aragonite, while the breeding enclosure of the paper boat ( Argonauta ) consists of the Kalkmodifikation calcite. The oldest paper boats are known from the Oligocene ( 33.9 / - 0.1 to 23.03 / - 0.05 million years ).
As already mentioned, the paper boats dioecious. The fertilization of the females is the same as with most octopuses by a specially redesigned arm of the males, the hectocotylus. Unlike other octopuses, however, the hectocotylus with the spermatophore releases from complete and can be found in the situation, even over long distances, a female and fertilize. According to the severed arm was scientifically lot formerly known as the male, but he was falsely described as a parasitic nematode in the mantle cavity of the female.
Art and Mythology
The scientific name Argonauta argo goes back to a mythological template. In the Argonautica itself makes the Greek hero Jason on his colleagues to capture the Golden Fleece. They are after their ship, the Argo, the Argonauts ( the drive on the Argo ) called.
Paper boats were a popular decorative motif in Minoan art and were often depicted particularly in marine style.