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That's certainly an important piece in the puzzle. If this has any 
bearing on Creationists, I'd also (strongly) recommend the book Why 
Darwin Matters by Michael Schermer.

martin weiss wrote:
> ISEN-ASTC-L is a service of the Association of Science-Technology Centers
> Incorporated, a worldwide network of science museums and related 
> institutions.
> ***************************************************************************** 
>
>
> From the New York Times, October 16 th
>
> This report presents further details for the evidence, from a fossil, 
> for the evolution of life forms from marine vertebrates into animals 
> that walked on land.
>
> Martin
>
>
> October 16, 2008
> Fish Fossil Yields Anatomical Clues on How Animals of the Sea Made It 
> to Land
> By JOHN NOBLE WILFORD
> In a new study of a fossil fish that lived 375 million years ago, 
> scientists are finding striking evidence of the intermediate steps by 
> which some marine vertebrates evolved into animals that walked on land.
>
> There was much more to the complex transition than fins evolving into 
> sturdy limbs. The head and braincase were changing, a mobile neck was 
> emerging and a bone associated with underwater feeding and gill 
> respiration was diminishing in size, a beginning of the bone’s 
> adaptation for an eventual role in hearing for land animals.
>
> The anatomy of this early transformation in life from water to land 
> had never before been observed with such clarity, paleontologists and 
> biologists said Wednesday in announcing the research.
>
> The scientists said in a report being published Thursday in the 
> journal Nature that the research exposed delicate details of the 
> creature’s head and neck, confirming and elaborating on its 
> evolutionary position as “an important stage in the origin of 
> terrestrial vertebrates.”
>
> In that case, the fish, a predator up to nine feet long, was a 
> predecessor of amphibians, reptiles and dinosaurs, mammals and 
> eventually humans. The fossil species was named Tiktaalik roseae, 
> nicknamed “fishapod” for its fishlike features combined with limbs 
> similar to those of tetrapods, four-legged land animals.
>
> The new research on the head skeleton of Tiktaalik (pronounced 
> tic-TAH-lick) was conducted at the Academy of Natural Sciences in 
> Philadelphia and the University of Chicago.
>
> “The braincase, palate and gill arch skeleton of Tiktaalik have been 
> revealed in great detail,” said Jason Downs, a research fellow at the 
> academy and lead author of the report. “By revealing new details of 
> the pattern of change in this part of the skeleton, we see that 
> cranial features once associated with land-living animals were first 
> adaptations for life in shallow water.”
>
> Several skeletons of the fish were excavated four years ago on 
> Ellesmere Island, in the Nunavut Territory of Canada, 700 miles above 
> the Arctic Circle, by a team led by Neil H. Shubin, an evolutionary 
> biologist at the University of Chicago and the Field Museum, and Ted 
> Daeschler of the Academy of Natural Sciences. The Devonian Age rocks 
> containing the fossils indicated that the fishapod lived in shallow 
> waters of a warm climate. It may have made brief forays on land.
>
> Since the discovery was reported in 2006, Dr. Downs and two specimen 
> preparators, C. Frederick Mullison of the academy and Bob Masek at 
> Chicago, spent more than a year prying deeply into the skulls of 
> several fishapod skeletons. The results were also analyzed by Dr. 
> Shubin and two other co-authors of the report, Dr. Daeschler and 
> Farish Jenkins Jr., an evolutionary biologist at Harvard.
>
> “Our work demonstrates that the head of these animals was becoming 
> more solidly constructed and, at the same time, more mobile with 
> respect to the body across this transition,” Dr. Daeschler said.
>
> Dr. Shubin said Tiktaalik was “still on the fish end of things, but it 
> neatly fills a morphological gap and helps to resolve the relative 
> timing of this complex transition.”
>
> For example, fish have no neck but “we see a mobile neck developing 
> for the first time in Tiktaalik,” Dr. Shubin said.
>
> “When feeding, fish orient themselves by swimming, which is fine in 
> deep water, but not for an animal whose body is relatively fixed, as 
> on the bottom of shallow water or on land,” he added. “Then a flexible 
> neck is important.”
>
> One of the most intriguing findings, scientists said, was the 
> reduction in size of a bony element that, in fish, links the 
> braincase, palate and gills and is associated with underwater feeding 
> and respiration. In more primitive fish, the bony part of what is 
> called the hyomandibula is large and shaped like a boomerang. In this 
> fossil species, the bone was greatly reduced, no bigger than a human 
> thumb.
>
> “This could indicate that these animals, in shallow-water settings, 
> were already beginning to rely less on gill respiration,” Dr. Downs 
> said, noting the specimen’s loss of rigid gill-covering bones, which 
> apparently allowed for increased neck mobility.
>
> In the transition from water to land, the researchers said, the 
> hyomandibula gradually lost its original functions and, in time, 
> gained a role in hearing. In humans, as in other mammals, the 
> hyomandibula, or stapes, is one of the tiny bones in the middle ear.
>
> As Dr. Daeschler said, “The new study reminds us that the gradual 
> transition from aquatic to terrestrial lifestyles required much more 
> than the evolution of limbs.”
>
...
-- 

           Wayne Watson (Watson Adventures, Prop., Nevada City, CA)

             (121.01 Deg. W, 39.26 Deg. N) GMT-8 hr std. time)
            
             "If /Stupidity/ got us into this mess, then why can't 
              it get us out?" -- /Will Rogers/
            
                    Web Page: <www.speckledwithstars.net/>

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