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Coelacanth Ho!

K

KeyserXSoze

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http://www.sundayherald.com/41695
Scientists sight ‘dinosaurs of the deep’ as African waters reveal new secrets

From Fred Bridgland in Johannesburg

German and South African scientists last week discovered more living specimens of a so-called Jurassic Park-style “living fossil” off the coast of Zululand than in any previous sightings.
Messages from the South African research ship Algoa said the expedition, led by Professor Hans Fricke, a German zoologist who is the world’s leading expert on the fish – known as the coelacanth – said seven of the fish, once thought to have become extinct 45 million years before man appeared on earth, have been seen at great depth.

The discoveries, made beyond Sodwana Bay, off the South African Zululand coast south of Mozambique, are the latest in a £3 million German-South African research programme that aims to reveal how the coelacanth has survived for 400m years while other species have become extinct. Seeing one, scientists say, is like getting a peek into prehistory.

The team from Bavaria’s Max Planck Institute and Rhodes University in Grahamstown is also seeking the answer to why no young coelacanths have ever been seen and how best to protect the species so that it survives a few more million years.

The coelacanth has the highest level of protection classification on the World Conservation Union’s Red List. South African scientists have made the coelacanth a mascot for their conservation movement. The ANC government hopes that the mysterious fish will improve public awareness of the environment, much as the giant panda has in China.

Fricke and his partner, Jurgen Schauer, made the latest finds during dives in their tiny bubble-shaped yellow submarine, the Jago, a kind of motorised decompression chamber which can withstand immense pressures and descend to 1200 ft.

The full import of their finds will only be known after the Algoa returns to port later this month. But at Sodwana Bay, part of a 200-mile-long land and marine reserve sheltering elephants, humpback whales and countless other creatures, coelacanth curio seller Ann Pape was thrilled by the news.

Pape, who peddles T-shirts, wire sculptures, pendants and other curios with coelacanth themes, said: “I’ve always had a fascination with them. It’s like our own Loch Ness monster. Not everyone is going to see it, but we know it’s there.”

The first coelacanth fossil record was discovered in a slab of marl slate in County Durham in 1839. That and subsequent discoveries dated the fossils as up to 410 to 450m years old. No fossils were found in rocks younger than 70m years, when the coelacanth was thought to have become extinct.

But on 23 December, 1938, scientists learned they were wrong. The trawler Nerine put into the South African port of East London and the skipper sent a message to the curator of the local museum that he had a pile of sharks, seaweed, rat-tail fishes, sponges, starfishes and sundry other things she could sort through as possible specimens for her displays.

She noticed a purple-blue fin sticking through the pile. It was attached to a strange five-foot-long fish covered in scales and with four limb-like fins. It was a “70m years dead” coelacanth, still considered the greatest zoological find of the last century.

It was 14 years before another coelacanth was found in the waters of the Comoros Islands, north of Madagascar. More specimens trickled in from other parts of the Indian Ocean. Always there, obsessed with the animal that intrigued him as a boy, was Fricke who, based on his observations, has estimated that no more than a thousand coelacanths survive in the deep canyons of the Indian Ocean.

After the first discovery, no other specimen was found in South African waters for 62 years. Then, in 2000, deep-water divers went in search of the fish in canyons off Sodwana Bay. They saw three coelacanths in underwater caves, but two of the divers lost their lives in decompression accidents.

The find led to the setting up of the South African Coelacanth Conservation Programme, based at Rhodes University and the Max Planck Institute.

Last week’s sightings were the 20th to 26th since the divers gave their lives in finding the first creatures four years ago.

Project manager, Tony Ribbink of Rhodes University, said: “The Sodwana discoveries are incredibly exciting. This fish is more than a fish. It’s a bit like finding a dinosaur at the bottom of your garden.”

02 May 2004
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I saw the first film made of them when it was shown at the Natural History Museum in London years ago and thought, 'Wow, coelacanths are ace. They do headstands underwater.' :)
 
Meet the fossil family

Thursday June 16, 2005
The Guardian

The coelacanths of the western Indian Ocean are all members of one extended family. Scientists had often wondered how different populations of these "living fossils" might differ. They wondered whether the fish, found thousands of miles apart in the region, might represent different genetic groups or even separate subspecies. But DNA analysis by Hans Fricke and colleagues at the Max Planck Institute for Behavioural Physiology in Tutzing reveals the close connection shared by the rare fish.

Fricke looked at the mitochondrial DNA of 47 coelacanths caught off Madagascar and East Africa. Mitochondria, the powerhouses of the body's cells, are passed directly from mother to child and mutation is rare. Therefore, their DNA sequences serve as a good marker of ancestry. Fricke found that his samples were remarkably similar - in most cases only differing by a single letter of DNA.

The direction of the region's prevailing currents, coupled with the fishes' natural lethargy, means that they are probably a slowly dispersing family hailing from the Comoros islands north of Madagascar, where they were discovered in 1952.
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www.guardian.co.uk/life/dispatch/story/ ... 48,00.html
 
Coelacanth

:_old: I seem to remember a report of the landing of one of these denizens of the deep, during the 2ndWW, and it being hailed as the answer to our food shortages. Alas, it was not to be, and we finished up with an uneatable creature known as "Snook".( My spelling may be suspect) :roll:
 
McCoelacanth? Preserve that Cod stock :lol: Seems, the story made it to the Telegraph today (but it doesn't add anything to the above).
 
Fisherman catches 'living fossil'

An extremely rare "living fossil" caught by a fisherman in Indonesia is being examined by scientists.
The 1.3m-long (4.3ft), 50kg (110lb) coelacanth is only the second ever to have been captured in Asia and has been described as a "significant find".

An autopsy and genetic tests are now being carried out to determine more about the specimen.

Coelacanths provide researchers with a window into the past; their fossil record dates back 350 million years.

These fish are odd in appearance, looking almost as if they have legs because of their large-lobed fins - they are sometimes dubbed "old four legs". The blue fish can also perform headstands, hovering with their head just over the sea floor, possibly to detect food.

Scientists previously thought the fish group had died out about 70 million years ago, but were shocked when in 1938 a species was caught in a fishing net off the coast of South Africa.

Since then, more than 300 of the modern coelacanth species (Latimeria chalumnae) have been found in the waters around the Comoros Islands, which are situated in the Western Indian Ocean, and the eastern coast of Africa.

However, scientists were surprised once again when a coelacanth was discovered thousands of kilometres away in Indonesia in 1998.

It looked similar to the coelacanths found near Africa, but genetic analysis revealed that the genomes differed by about 3.5%, and it was described as a new species called Latimeria menadoensis.

Peter Forey, a coelacanth expert at the Natural History Museum, London, said: "When the Indonesian coelacanth turned up in 1998, lots of people went out to look for more around this area, but nobody ever saw anything until now.

"The fact that another specimen has been found is significant; it confirms that this is a genuine location for another coelacanth's population."

A fearsome catch

Justinus Lahama, an Indonesian fisherman, caught the fish two months ago off the coast near Manado, on northern Sulawesi Island.

He told AFP news agency: "It was an enormous fish. It had phosphorescent green eyes and legs.

"If I had pulled it up during the night, I would have been afraid and I would have thrown it back in."

He took the catch back to the port where it remained alive for 17 hours in a netted pool outside of a restaurant. It was then frozen and is now being examined by scientists.

Genetic fingerprinting tests to be carried out by an international team of scientists will confirm if it is the same species as the coelacanth found in 1998.

The tests, said Dr Forey, could also help to reveal more about how and why the two species exist thousands of kilometres apart.

"The fact that the two populations are separated by this enormous gap of thousands of miles begs the question of how long ago and why they separated," he said.

"Estimates from the genetic fingerprinting carried out on the fish caught in 1998 suggest that they separated about four to five million years ago, however if you look at the geology of the oceans, it suggests that they should have separated about 30 million years ago.

"More sequences taken from this new fish will help us to calibrate these estimates."

Various efforts to conserve these ancient fish are underway. They are considered to be endangered and are protected by the Convention on International Trade in Endangered Species (CITES).

On Wednesday, another group of scientists announced that they had discovered a 400-million-year-old fossil of a coelacanth fin.

The find was reported in the journal Evolution and Development.

Researchers from the University of Chicago said it had been excavated from sediments at Beartooth Butte in northern Wyoming and would reveal more about the evolution of the creatures.

http://news.bbc.co.uk/1/hi/sci/tech/6925784.stm
 
Scientists capture world's first images of baby coelacanth fish - dubbed a 'living fossil'
By Daily Mail Reporter
Last updated at 10:56 AM on 18th November 2009

Scientists have captured the world's first images of a baby coelacanth - an extremely rare type of fish known as a 'living fossil'.
Japanese marine researchers have found and successfully filmed the young fish at a depth of 528ft in Manado Bay off Sulawesi Island, Indonesia.

Video footage shows the 12.6-inch coelacanth, coloured blue with white spots, swimming slowly among rocks on the seabed for about 20 minutes.

'As far as we know, it was the first ever video image of a living juvenile coelacanth, which is still shrouded in mystery,' said Masamitsu Iwata, a researcher at Aquamarine Fukushima in Iwaki, northeast of Tokyo.
Scientists hope the discovery will shed light on the habitat and breeding habits of coelacanths.

The researchers used a remotely operated, self-propelled vehicle to film the coelacanth, which appeared to be newly born, Iwata said.

A similar-sized juvenile was once discovered in the belly of a pregnant coelacanth. It is believed that their eggs hatch inside the female and the young fish are fully formed at the time of birth.

Coelacanths are commonly regarded as having evolved little from prehistoric times and were thought to be extinct until a living specimen was discovered in 1938 off the coast of southern Africa.

http://www.dailymail.co.uk/sciencetech/ ... -fish.html
 
'Living fossil' coelacanth genome sequenced
By Rebecca Morelle
Science reporter, BBC World Service
http://www.bbc.co.uk/news/science-environment-22184556

The coelacanth is thought to have changed very little over millions of years

The genetic secrets of a "living fossil" have been revealed by scientists.

Researchers sequenced the genome of the coelacanth: a deep-sea fish that closely resembles its ancestors, which lived at least 300 million years ago.

The study found that some of the animal's genes evolved very slowly, giving it its primitive appearance.

The work also shed light on how the fish was related to the first land-based animals.

The coelacanth has four large, fleshy fins, which some scientists believe could have been the predecessors of limbs.

It had been suggested that this fish was closely related to early tetrapods - the first creatures to drag themselves out of the ocean, giving rise to life on land.

But the study, published in the journal Nature, suggested that another fish called the lungfish, which also has four limbs, had more genes in common with land-based animals.

Slow to change

The coelacanth can reach up to 2m-long and is found lurking in caves deep beneath the waves.

It was thought to have been extinct for millions of years, until it turned up in a trawlerman's net off the coast of Africa in 1938.

Its ancient appearance has earned it the title "living fossil" - but it is so elusive, that it has been hard to study.

To find out more, an international team of researchers sequenced the coelacanth's genome, which contained nearly three billion DNA bases.

Continue reading the main story
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The lungfish-coelacanth question has gone back and forth over the years”

Prof John Hutchinson
Royal Veterinary College
Professor Kerstin Lindblad-Toh, from the University of Uppsala in Sweden and the Broad Institute of MIT and Harvard in the US, said: "What we can see is that while the genome as whole changes, the protein-coding genes - that make the living fish - are much more stable and much more unchanging.

"And if you think about it, this might be correlated to the fact that the coelacanth lives in a rather extreme and stable environment.

"It lives several hundred metres down in the ocean, and it may also be in an environment where it doesn't have a lot of competitors. So maybe it adapted to that environment a long time ago and it doesn't have a huge need for change."

The researchers also used the study to try and solve the long-standing question of whether the first tetrapods were more closely related to the coelacanth or the lungfish.

They compared DNA profiles of both of these fish with modern land-based animals, including mammals, birds and lizards.

"We selected 251 genes that were very similar in all these genomes so we could build this picture of how closely related these species were," Prof Lindblad-Toh explained.

"From that picture it was clear the lungfish is closer to tetrapods than the coelacanth."

Commenting on the research, John Hutchinson, professor of evolutionary biomechanics from the Royal Veterinary College, said it was an interesting study.

"The lungfish-coelacanth question has gone back and forth over the years; the lungfish answer is not new, but this is a much better, bigger dataset so it does tip the balance a bit," he said.

"They are missing some critical animals - it would be interesting to see what addition of salamander or more ray-finned fish would do to their analysis, but it might not change anything important."

This study is not the only one attempting to understand the coelacanth.

Since the fish was rediscovered in the 1930s, only a few hundred have ever been found, many of these dead caught up in trawls.

Scientists from the French organisation Andromede Oceanology are working with the Natural History Museum in Paris to attach acoustic tracking devices to the fish in order to study their behaviour and capture 3D moving images of their fins as they swim.
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It may have hidden in the ocean for millions of years, but life today poses numerous challenges for the West Indian Ocean coelacanth (Latimeria chalumnae), the “living fossil” fish that was famously rediscovered off the coast of South Africa in 1938. The few areas in which the fish still swim face destruction from new port construction while the coelacanths themselves risk being caught up in fishing nets intended for sharks. Even climate change poses a new risk for the species.

The coelacanth already has a few protections in place—trade is banned under the Convention on International Trade in Endangered Species, for example—but now one more safeguard may soon be available. The National Marine Fisheries Service (NMFS) proposed this week that coelacanths be listed as “threatened” under the Endangered Species Act (ESA). ...

http://blogs.scientificamerican.com/extinction-countdown/2015/03/04/coelacanth-endangered/
 
A new study has found that coelacanths can live for up to a century.

"A "living fossil" fish can live for an impressively long time - perhaps for up to a century, according to a new study.

The coelacanth was thought to have a life span of around 20 years, but new estimates suggest it is a centenarian of the ocean, alongside sharks.

French researchers studied marks on the scales of museum specimens - much like tree rings tell the age of trees.

They believe the fish reproduces only in late middle age and can be pregnant for as long as five years."

https://www.bbc.com/news/science-environment-57518593
 
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