Zuiyō Maru

The "Zuiyō Maru" (瑞洋丸, ずいようまる) was a Japanese fishing trawler that caught a creature initially claimed to be a prehistoric plesiosaur off the coast of New Zealand in 1977. Although several Japanese scientists insisted it was "not a fish, whale, or any other mammal" [cite book | last = Ellis | first = Richard | authorlink = | coauthors = | title = Monsters of the Sea | publisher = First Lyons Press | date = 2006 | location = Guilford, Connecticut | pages = 68 | url = | doi = | id = | isbn = 978-1-59228-967-7 ] , analysis later indicated it was most likely the carcass of a basking shark by comparing the number of sets of amino acids in the muscle tissue Fact|date=March 2008.

Discovery

On April 25, 1977, the Japanese trawler "Zuiyo Maru", sailing east of Christchurch, New Zealand, caught a strange, unknown creature in the trawl. The crew was convinced it was an unidentified animal (Bord, 1990), but despite the potential biological significance of the curious discovery, the captain, Akira Tanaka, decided to dump the carcass into the ocean again so not to risk spoiling the caught fish. However, before that, some photos and sketches were taken of the creature, nick-named "Nessie" by the crew, measurements were taken and some samples of skeleton, skin and fins were collected for further analysis by experts in Japan. The discovery resulted in immense commotion and "plesiosaur-craze" in Japan, and the shipping company ordered all its boats to try to relocate the dumped corpse again, but with no apparent success. (Sjögren, 1980).

Description

The foul-smelling, decomposing corpse weighed 1800 kg and was about 10 m long. According to the crew, the creature had a one and a half meter long neck, four large, reddish fins and a tail about two meters long. It lacked a dorsal fin. No internal organs remained, but flesh and fat was somewhat intact (Sjögren, 1980 and Welfare & Fairley, 1981).

Proposed explanations

Plesiosaur

Professor Tokio Shimaka from Yokohama University was convinced that the remains was of a supposedly extinct plesiosaur. Dr Fujiro Yasuda from Tokyo university agreed with Shimaka that "the photographs show the remains of a prehistoric animal" (Sjögren, 1980).

However, other scientists were more skeptical. According to Bengt Sjögren (1980), the Swedish paleontologist Hans-Christian Bjerring was soon interviewed by Swedish TT, and said:

"If it's true that the Japanese collected samples of fins and skin, it would be possible to conclude from a microscope what it is. If it would be shown to be a hitherto unknown animal from the sea, it is as big of a sensation as the discovery of the coelacanth in 1938... but there is reason to be suspicious of the claims of plesiosaurs, for example, as the marine environment and fauna changed drastically since the age of the plesiosaurs on earth."

Another Swedish scientist, Ove Persson, was also critical of the plesiosaur interpretation Fact|date=March 2008. He recalled other discoveries of similar dead marine creatures resembling plesiosaurs that on closer inspection revealed them to be just decomposed, unusually large sharks. He also added, according to Sjögren (1980), "The discovery of the coelacanth was not as strange as if a plesiosaur would be discovered. The plesiosaur is much bigger and breathes with lungs. It seems incredible that it would manage to remain hidden."

Basking Shark

On July 28, 1977, the "Zuiyo Maru" carcass was commented upon in the international science magazine "New Scientist". A scientist from the Natural History Museum in London had the same opinion as Bjerring and Persson: that the remains were not from a plesiosaur. The decomposition pattern of a basking shark, whose spine and braincase is relatively highly ossified for a cartilaginous fish, can be expected to produce a similar shape to a plesiosaur; the first parts that fall off during decomposition are the lower jaw, the gill area, and the dorsal and caudal fins. Bengt Sjögren (1980) concluded, "it was the infamous old ´Stronsay beast´ that once again haunted like on innumerable other occasions. The scholars in Japan went into the same easy trap as the Scot naturalists did in the 19th century."

However, some Japanese scientists criticised the shark hypothesis. Professor Yoshinori Imaizumi of the National Science Museum of Japan said Fact|date=March 2008, "It's not a fish, whale, or any other mammal." and Professor Toshio Kasuya agreed Fact|date=March 2008, "If it was a shark, the spine would be smaller, and the neck itself is too long as shown in the picture. I think we can exclude the fish theory."

The above mentioned Fujiro Yasuda ruled out a mammalian origin and claimed: "No animal of that size has such an elongated body" (Welfare & Fairley, 1981). He concluded that the stretching of the body and positions of fins were totally different from that of any known shark, and added: "We can't find any known species of fish that correspond with the animal caught outside New Zealand. If it is a shark, it is a species unknown to science." Two other Japanese scientists, Obata and Tomata from Tokyo National Museum of Science also agreed that no known species or genus of animal fit the appearance of the "Zuiyo Maru" creature.

Popular culture

This incident was mentioned briefly in the 1991 film "Godzilla vs. King Ghidorah".

ee also

*Basking shark
*Globster
*Plesiosaur
*Stronsay beast

External links

(May include sites of questionable scientific integrity)
* [http://paleo.cc/paluxy/plesios.htm Sea-monster or Shark?]
* [http://www.cryptozoology.st/artiklar_zuiyo_maru.html The Zuiyo Maru explanation is a basking shark hoax]
* [http://www.americanmonsters.com/monsters/carcass/index.php?detail=article&idarticle=62 Zuiyo Maru Carcass at American Monsters]
* [http://www.angelfire.com/mi/dinosaurs/zuiyomaru.html Zuiyo-maru carcass Plesiosaur or Basking Shark?]

References

* Bord, Janet and Colin (1990), in "Varelser från det okända" (Det oförklarliga), Bokorama.
* Sjögren, Bengt, "Berömda vidunder", Settern, 1980, ISBN 91-7586-023-6 sv icon
* Welfare&Fairley (1981), "Arthur C. Clarkes gåtfulla värld", Bonnier Fakta.