Two articles: Walking fish and a transitional fossil found

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steve001

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Walking fish reveal how our ancestors evolved onto land
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About 400 million years ago a group of fish began exploring land and evolved into tetrapods – today's amphibians, reptiles, birds, and mammals. But just how these ancient fish used their fishy bodies and fins in a terrestrial environment and what evolutionary processes were at play remain scientific mysteries.
Researchers at McGill University published in the journal Nature, turned to a living fish, called Polypterus, to help show what might have happened when fish first attempted to walk out of the water. Polypterus is an African fish that can breathe air, 'walk' on land, and looks much like those ancient fishes that evolved into tetrapods. The team of researchers raised juvenile Polypterus on land for nearly a year, with an aim to revealing how these 'terrestrialized' fish looked and moved differently.

"Stressful environmental conditions can often reveal otherwise cryptic anatomical and behavioural variation, a form of developmental plasticity", says Emily Standen, a former McGill post-doctoral student who led the project, now at the University of Ottawa. "We wanted to use this mechanism to see what new anatomies and behaviours we could trigger in these fish and see if they match what we know of the fossil record."



Read more at: http://phys.org/news/2014-08-fish-reveal-ancestors-evolved.html#jCp



First amphibious ichthyosaur discovered, filling evolutionary gapFirst amphibious ichthyosaur discovered, filling evolutionary gap
The first fossil of an amphibious ichthyosaur has been discovered in China by a team led by researchers at the University of California, Davis. The discovery is the first to link the dolphin-like ichthyosaur to its terrestrial ancestors, filling a gap in the fossil record. The fossil is described in a paper published in advance online Nov. 5 in the journal Nature.
he [URL='http://phys.org/tags/fossil/']fossil represents a missing stage in the evolution of ichthyosaurs, marine reptiles from the Age of Dinosaurs about 250 million years ago. Until now, there were no fossils marking their transition from land to sea.

"But now we have this fossil showing the transition," said lead author Ryosuke Motani, a professor in the UC Davis Department of Earth and Planetary Sciences. "There's nothing that prevents it from coming onto land."

Motani and his colleagues discovered the fossil in China's Anhui Province. About 248 million years old, it is from the Triassic period and measures roughly 1.5 feet long.


Read more at: http://phys.org/news/2014-11-amphibious-ichthyosaur-evolutionary-gap.html#jCp[/URL]
http://phys.org/news/2014-08-fish-reveal-ancestors-evolved.html#jCp

http://phys.org/news/2014-08-fish-reveal-ancestors-evolved.html#jCp
 
Is the animal really transitional or merely one type of creature uniquely adapted to its environment? It's easy enough to look at this both ways.
 
Why couldn't that species be a biological absurdity like the hundreds of other biological absurdities?
 
fire said:
Why couldn't that species be a biological absurdity like the hundreds of other biological absurdities?
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Huh? Do you mean for example, all of the extinct hominid species? Define absurd. Nature does not make such a distinction.
 
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The discovery of this fish isn't really new is it? Remember seeing this years ago. These fishes, for some reasons, were struggling in small puddles of water and was pushing themselves all the time to be up on land, and travel on dry land between puddles to get a sip of "air" (water). What compels them to do this is a mystery though. Some species has, IIRC, been going from being fishes, to being land-animals, and then again going back to the ocean. Why they do this, and why they put themselves through it is quite hard to understand, because it cant be some sort of lack of food, or some quick environment-changes, because this transition takes time - and lots of it - and it must be quite painful.
 
Bart V said:
What's a biological absurdity?
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The narwhale, the star-nosed mole, the platypus. How do we know this creature is simply not an anomaly? What proof is there that this particular species is actually a link between those who swam and those who walked?

I don't have any skin in this game. I don't give a crap either way. But there are a lot of odd creatures out there. Just because we find a fish that walks doesn't mean it is somehow the missing link unless there is other evidence to back this up.
 
Pollux said:
The discovery of this fish isn't really new is it? Remember seeing this years ago. These fishes, for some reasons, were struggling in small puddles of water and was pushing themselves all the time to be up on land, and travel on dry land between puddles to get a sip of "air" (water). What compels them to do this is a mystery though. Some species has, IIRC, been going from being fishes, to being land-animals, and then again going back to the ocean. Why they do this, and why they put themselves through it is quite hard to understand, because it cant be some sort of lack of food, or some quick environment-changes, because this transition takes time - and lots of it - and it must be quite painful.
Click to expand...

I'm not even going to go back to the Sandy Hook thread to read your reply to my comment. I don't care.
 
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