* Astronomy

Members Login
Post Info TOPIC: Ancient Fish


L

Posts: 131433
Date:
Notogoneus osculus
Permalink  
 


Lake-bed trails tell ancient fish story

The wavy lines and squiggles etched into a slab of limestone found near Fossil Butte National Monument are prehistoric fish trails, made by Notogoneus osculus as it fed along a lake bottom, says Emory University palaeontologist Anthony Martin.
He led a detailed analysis, published May 5 in PLoS One, that gives new insights into the behaviour of the extinct N. osculus, and into the ancient ecology of Wyoming's former Fossil Lake.

Read more

__________________


L

Posts: 131433
Date:
Coelacanth
Permalink  
 


A research team from Indonesia's Sam Ratulangi University, Indonesian Science Institution and Fukushima Aquamarine Japan on Monday once again found prehistoric fish called coelacanth at Talise waters of North Minahasa in 155 meter-depth.

Read more

__________________


L

Posts: 131433
Date:
RE: Ancient Fish
Permalink  
 


Swedish researcher finds missing piece of fossil puzzle
The mode of reproduction seen in modern sharks is nearly 400 million years old. That is the conclusion drawn by Professor Per Erik Ahlberg, Uppsala University, from his discovery of a so-called "clasper" in a primitive fossil fish earlier this year. The research results are published today in Nature.
In February this year, a paper published in Nature by a team of Australian and British researchers showed that placoderms, a group of ancient fishes that died out more than 350 million years ago, gave birth to live young. Beautifully preserved fossil embryos in the body cavity of the placoderm Incisoscutum showed that these fishes, close to the common origin of all jawed vertebrates, had a mode of reproduction similar to modern sharks. Live birth requires internal fertilisation; sharks achieve this by using a "clasper", an extension of the pelvic fin that functions like a penis. The authors looked for a clasper in their placoderm fossils but couldn't find one, so they were forced to argue that it had been made of soft cartilage and had not been preserved.
Shortly afterwards, Per Erik Ahlberg from Uppsala University visited one of the Australian researchers and spotted a perfectly preserved bony clasper in one of their Incisoscutum fossils.

Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

How did piranhas - the legendary freshwater fish with the razor bite - get their telltale teeth? Researchers from Argentina, the United States and Venezuela have uncovered the jawbone of a striking transitional fossil that sheds light on this question. Named Megapiranha paranensis, this previously unknown fossil fish bridges the evolutionary gap between flesh-eating piranhas and their plant-eating cousins.
Present-day piranhas have a single row of triangular teeth, like the blade on a saw, explained the researchers. But their closest relatives - a group of fishes commonly known as pacus - have two rows of square teeth, presumably for crushing fruits and seeds.

"In modern piranhas the teeth are arranged in a single file. But in the relatives of piranhas - which tend to be herbivorous fishes -the teeth are in two rows" - Wasila Dahdul, a visiting scientist at the National Evolutionary Synthesis Centre in North Carolina.

Read more

__________________


L

Posts: 131433
Date:
Materpiscis attenboroughi
Permalink  
 


A 380-million-year-old fossil fish from the Kimberley has been hailed as one of the most important species discoveries of the past year.
It showed that sex in vertebrates evolved millions of years earlier than experts had thought.
The primitive fish, named Materpiscis attenboroughi, was described as "the world's oldest mother" when it was unveiled.

Read more


The species was named Materpiscis attenboroughi in honour of David Attenborough who first drew attention to the significance of the Gogo fish sites in his 1979 series Life on Earth.

Source

__________________


L

Posts: 131433
Date:
RE: Ancient Fish
Permalink  
 


A significant fish fossil has been discovered on New South Wales's far south coast that is thought to be the largest of its kind in the world.
Australian National University palaeontologist Gavin Young says a 40-millimetre tooth was excavated near Eden late last year.

Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

The genetic toolkit that animals use to build fins and limbs is the same genetic toolkit that controls the development of part of the gill skeleton in sharks, according to research to be published in Proceedings of the National Academy of Sciences on March 23, 2009, by Andrew Gillis and Neil Shubin of the University of Chicago, and Randall Dahn of Mount Desert Island Biological Laboratory.

"In fact, the skeleton of any appendage off the body of an animal is probably patterned by the developmental genetic program that we have traced back to formation of gills in sharks. We have pushed back the evolutionary origin of the developmental genetic program that patterns fins and limbs" - Andrew Gillis, lead author of the paper and a graduate student in the Department of Organismal Biology and Anatomy at the University of Chicago.

See more

__________________


L

Posts: 131433
Date:
Permalink  
 

Large size and a fast bite spelled doom for bony fishes during the last mass extinction 65 million years ago, according to a new study to be published March 31, 2009, in the Proceedings of the National Academy of Sciences.
Today, those same features characterise large predatory bony fishes, such as tuna and billfishes, that are currently in decline and at risk of extinction themselves, said Matt Friedman, author of the study and a graduate student in evolutionary biology at the University of Chicago.

Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

A fossil fish is shedding light on the evolution of jawed vertebrates.
It is one of the earliest known jawed fish in the fossil record, a scientist from Uppsala University, Sweden, reports in the journal Nature.
The specimen is the first example of a well-preserved braincase of a group of extinct fish called acanthodians from the Palaeozoic era.


Read more

__________________


L

Posts: 131433
Date:
Dunkleosteus
Permalink  
 


Palaeontologists, meeting in Cleveland, hunt fossils of ancient fish Dunkleosteus
Bob Carr, Glenn Storrs and George Kampouris are fishing on the banks of Big Creek this warm autumn afternoon, but they're not using bait and tackle.
Sledgehammers, pry bars, ladders and rappelling gear are their tools of choice. The aquatic quarry they're after has been dead for at least 350 million years, and it's more elusive than any trout or bass. It's fossilised, entombed in the shale cliff faces that rise 50 feet or more above the meandering brook.

Read more

__________________
«First  <  1 2 3 4 5 6  >  Last»  | Page of 6  sorted by
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard