New revelations about an ancient fish: The secret to swimming upside down

One of the world's rarest fish, the Coelacanth, has been discovered after an after-hours trip to a hospital. The specimen of this primordial fish that was removed from its jar of alcohol gave researchers new insight into how it works. The deep sea dweller is in danger of extinction.

It was like finding a living dinosaur when a fisherman in South Africa caught a coelacanth in his net in 1939. The coelacanth was thought to have died out 66 million years ago. About 300 fossils of this living fossil have been caught around the world since then. For 60 years, a single fish, "specimen number 23," has been submered in alcohol at the Zoological Museum in the Danes.

The coelacanth's body is no secret. The way the fish works is not known. New things have been discovered about the deep-sea dweller by researchers.

The fish is shrouded in mystery. It's difficult to see it because it lives in underwater caves. Since a large portion of the few specimen collected have been cut to pieces, new methods were needed to find out more about how it lives. Peter Mller is an associate professor at the University of Copenhagen's Natural History Museum ofDenmark. He is one of the authors of the research article.

Mller is one of the first people to conduct research on a specimen that has been preserved intact and only been used for display.

Swimming upside down has a secret.

The research scientists were able to model the fish with more precision and not destroy them. The models show the distribution of bones and fat. Among other things, the models help explain the unique "headstand drift hunting" technique of the coelacanth, whereby it slowly drift along a seabed vertically, head and snout downwards, as it uses an electronic organ to find food in the water.

There is a lot of bone mass in the head and tail of the coelacanth. It's unusual. It's easy for the fish to stand on its head if it's at either end of the fish. The balance point is an advantage for the way of life.

The researchers found out that coelacanth don't have a regular gas swim bladder like modern fish, and that they have a different distribution of fat in their body. There is a correlation between the fat content of the fish and the depths at which they live.

For five years, a pregnant woman can give birth.

Females gestate for a full five years before giving birth. One of the great mysteries of coelacanth is where it gives birth. The Danes hope to answer this question soon.

They don't know where their fry are born. By analyzing the distribution of bone and fat in a fetus, we can figure out what depth fry are made of. When we don't know where they are, we don't know where to protect them. There is cause for worry. The slow reproduction rate of coelacanth makes them vulnerable.

The researchers say that their models can be used to determine if organisms are adapted to the ocean depths at which they live. Climate change could cause ocean currents to change and affect marine life.

Modern scanning techniques have allowed us to perform exciting new analyses despite the animal having been submersed in alcohol for decades. The world's best secondhand store has a lot of recycled things that can't be found new.

The story of the Danes.

• The Danish coelacanth specimen -- specimen no. 23 -- was caught in the Indian Ocean's Comoros archipelago in 1960. At the time, the Comoros was a French colony.
• Danish oceanographer Anton Bruun, leader of the Galathea-2 expedition among other things, persuaded France to donate the specimen to the Zoological Museum in 1962.
• With the donation came strict requirements that the specimen was only to be used as a display item and could under no circumstances be subjected to dissection.
• While this requirement was unofficially lifted in 1975 when the Comoros gained independence from France, Copenhagen chose to honour the original agreement. Consequently, specimen 23 was kept intact.
• Over the years, the specimen has been exhibited at the Zoological Museum and the former Denmark's Aquarium.

There are facts about Coelacanth.

• There are two living species of coelacanth -- Latimeria chalumnae, which lives off the coast of East Africa, and Latimeria menadoensis, which lives off Indonesia.
• The oldest known coelacanth fossils are more than 410 million years old.
• Just over 300 live specimens of coelacanth are believed to have been caught worldwide.
• Coelacanth are pregnant for five years and birth live young.
• Coelacanth grow up to 2 meters long and weigh up to 100 kilograms.
• The IUCN has classified the East African coelacanth as critically endangered and the Indonesian species as vulnerable.

There is a story

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