The nasty and invasive snakehead fish can move on land for a period of time, maybe they are related.
Facinating - all of it.
Great pictures. Wowsa.
I'll browse those links later.
The paper today had a neat illustration...what a jolt
The folks in S&R have already been given the sad news--and have already mounted (or attempted to mount) an attack no the findings.
I have to admit...when I read that this fish evolved 350 million years ago...I thought about the folks in S&R
this probably deserves its own thread, but ...
Quote:A Link in Lucy's Past
Paleoanthropologist Tim White of the University of California, Berkeley, and his colleagues have unearthed fossils representing the oldest species of Australopithecus, Au. anamensis, in northeastern Ethiopia's Middle Awash valley. The 4.1-million- to 4.2-million-year-old remains--including jaw fragments, teeth and a femur--extend the range of this hominid, which was previously known only from two sites in Kenya. And in terms of age and anatomy, they are intermediate between two other hominids found in the Middle Awash: the older Ardipithecus ramidus and the younger Au. afarensis (Lucy's species).
link
and the Nature
link ...
Quote:The origin of Australopithecus, the genus widely interpreted as ancestral to Homo, is a central problem in human evolutionary studies. Australopithecus species differ markedly from extant African apes and candidate ancestral hominids such as Ardipithecus, Orrorin and Sahelanthropus. The earliest described Australopithecus species is Au. anamensis, the probable chronospecies ancestor of Au. afarensis. Here we describe newly discovered fossils from the Middle Awash study area that extend the known Au. anamensis range into northeastern Ethiopia. The new fossils are from chronometrically controlled stratigraphic sequences and date to about 4.1-4.2 million years ago. They include diagnostic craniodental remains, the largest hominid canine yet recovered, and the earliest Australopithecus femur. These new fossils are sampled from a woodland context. Temporal and anatomical intermediacy between Ar. ramidus and Au. afarensis suggest a relatively rapid shift from Ardipithecus to Australopithecus in this region of Africa, involving either replacement or accelerated phyletic evolution.
<Setanta wondered why I was whoooooooohooooooooooing - now he understands>
Whooooooooooohooooooooooooooooo
~~~~~~~~~~
Kinda wish I was about 16 and just starting to really study science right now.
Tiktaliik didnt move on land, Ted Daeschler of the Philly Academy, and a member of the team, had already found the fossil of the first land walking relative of Tiktak. It comes from the upper Mid Devonian of about 10 to 20 million years later than this.
The thing that is not appreciated in all the "banner tape news" formats, where these kind of discoveries are almost expected to be daily reports, Ted ANS NOTHER COLLEAGUE FROM Harvard have been working on these types of creatures for over 10 years before theyve become overnight celebrities. The bullshit work in the badass climate and suroundings of Ellsmere, and the crappy road cuts of Upstate Pennsylvania , require a methodical earch plan and keen senses of stratigraphy. The redbeds where these fossils came from , are interpreted to be shallow braided streams that drained uplands. The ability to pick out the stream deposits from the mudbanks or wetlands, is important and imagine , they covered over 600 search acres last 2 years in a total of 12 weeks at 6 weeks per summer. Mosquitoes and midges, noseeums and polar bears were a problem. These guys lived sparely and were never really warm.
(Ive heard Ted tell his story that always buries the romance and the Indiana Jones stuff, beneath the reality of the harsh environment and the "realities" of the project budget.
No Creationist would even have a clue where to startr, how to start, or even why look. Theyd be busy trying to slash and burn what could be one of the greatest finds since archeopteryx..
(descending from soapbox and sitting down )
Farmerman, on or off the soap box works for me.
From Beth's first link:
Quote:AN EVOLUTIONARY missing link that was among the first fish to leave the sea and walk on land has been unearthed in the Canadian Arctic.
Tiktaalik roseae, which lived about 375 million years ago, has features that blur the distinction between fish and terrestrial limbed creatures.
They have allowed scientists to freeze-frame a process of adaptation to land that took tens of millions of years
I'm interested, because it's generally interesting, but especially because you said:
Quote:Tiktaliik didnt move on land, Ted Daeschler of the Philly Academy, and a member of the team, had already found the fossil of the first land walking relative of Tiktak. It comes from the upper Mid Devonian of about 10 to 20 million years later than this.
See? I don't know this. Tell me more. What's it called?
The team members were quite specific about the evolutionary advances this fish attained. However, there was no evidence that it hopped about on land, mostly because the ray fins hadnt developed the support bones that the later specimens that Daeschler fopund in upper Pa. Its a small thing but, newspapers want to glam up a find beyond its real truth. The fish had enough "missing link" advances that would demonstrate to just about anyone who saw it that this was a big jump in evo/devo.
The fact that it had a shoulder girdle and the attached ray bones that would later become the feet were there. So was the lack of the "plates" that keep a fish from turning its head. This guy could move its head about.(Ya have to recall that the earliest fish were placoderms and ostracoderm which were primitive armored fish that lived well into the Devonian. A special kindcalled Eusthenopteron had many of the features that tiktaliik had but had no shoulder girdle.
There was a big blank area until the Mid mississippean when some 'fish like' amphibians called Ichthyostega appeared in the "Old Red Sandstones" of England (remember the continents were still joined together) So, with these last fossils, we have a pretty good step-by-step appearance of various "water-to-land" features that, although the species are no more than distant cousins, they show remarkeable convergence of features. Its as if, a feature, once it appeared, began to be included into the developing body plan of more complex animals. The old paleo book by Colbert (an intro text I had used in undergrad work) has been slowly been filling in with new information. I looked up Eusthonopteron and , in his Book, Colbert stated that, "we shall probably never know the steps that evolution had made when fish evolved into land dwelling animals" Well ol Doc Colbert would be pleased to know that these guys, after mucking about for 2 and more years, have found some really compelling evidence.
Pardon me , I get all excited about these things (Im such a weenie) but the earliest fish like amphibian was Icthyostega. Im not sure what Daeschler had named his find from Heiner Pa. he mentioned it once at a seminar but Ive forgotten. It was a bit more primitive than Ichthyostega.
farmerman wrote:Pardon me , I get all excited about these things (Im such a weenie) but the earliest fish like amphibian was Icthyostega. Im not sure what Daeschler had named his find from Heiner Pa. he mentioned it once at a seminar but Ive forgotten. It was a bit more primitive than Ichthyostega.
Hehehheh. Yer many things I'm pretty sure, but *weenie* ain't one of them.
Thanks for the info. If I haven't used the word interesting too often about this subject, let me use it again! Damn right.
farmerman, I definitely 'get' papers glamming things up, but I'd never considered Nature a journal that went that way. Do you think I should be looking at things published in Nature more critically?
<Joeblow - thought of you tonight - went to New World/Kim Hoa and admired the bbq'd pig heads>
That got me snorking Beth... I mean that you thought of me and pig's heads together....
Yer sentimental, ain'tcha?
Heeheeeee.
Me, too.
You know me too well, Joeblow.
ehbeth. Nature doesnt usually take leaps without good data. If the Ellsmere crew had found indesputable evidence(like tracks) of tiktaliik on flood plain soils or something more definitive, then Id agree that this fish walked on land..as it is, were guilty of "functional projection'
The article in NAture was by the team, your article from the Times was by a science reporter, WHO WAS probably quoting from Nature. The reporter was only, paraphrasing, and he was insertinga bit more than the Nature article actually implied.
Daescler himself has said that this fish was a kind of structural intermediate that "may" have been a precursor to amphibians like icthyostega.In hi seminars hed never said that this one frequented night spots on land.
farmerman - one of my links was to the Nature article. That's why I asked.
Ive talked with the people at the Philly Academy and they really dont feel that this fish was a land hopper , its fins werent really equipped and Daeschlers later specimens from upstates Pa are definately those of a type just less developed than icthyostega. I obviously cannot argue that the articles title is a clear "catchphrase" but will stand firm on the knowledge imparted to me by one of the authors that they werent conveying that Tiktaliik was even able to crawl out on water. Daeschler was more saying that the fish could represent a bodyplan that would eventually lead to an obligate landweller.
One thing that this conversation has been good for is to make the point that most scientists arent quick to reach unsupportable conclusions , they know that some other data may fill in the gap even closer. Its the composition of the digits that has Daeschler convinced that walking (or hopping) on land came later, many of these lobe finned fidhes had as many as 8 proto digits and that fact states loudly that these were, in many cases natures "trial balloons"
