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Ancient flatfish shows only partially migrated eyes

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From “Mystery of the Flatfish Head Solved” (ScienceDaily, June 25, 2012), we learn:

A new fossil discovery described in the latest issue of the Journal of Vertebrate Paleontology by Oxford University researcher Dr Matt Friedman finally solves the mystery. Friedman’s fossil fish, named Heteronectes (meaning ‘different swimmer’), was found in 50 million year old marine rocks from northern Italy. This study provides the first detailed description of a primitive flatfish, revealing that the migrated eye had not yet crossed to the opposite side of the skull in early members of this group. Heteronectes, with its flattened form, shows the perfect intermediate stage between most fish with eyes on each side of the head and specialized flatfishes where both eyes are on the same side.

Interesting. In living flatfish, the migration takes place during the fish’s lifetime. Here’s how it works:

North Pacific Halibut, a member of the Flounder Family of fish, are unique because they have a biological characteristic that only the Flounder Family has. When they are first hatched from the egg they swim upright and have one eye on each side of their head like all other species of fish. At about five weeks of age and one inch in length, one eye “migrates” over the top of the head so that both eyes are on the same side of the head. At this time the juvenile Halibut “lays over” on its’ side with both eyes on the upward or top side. As the fish grows the under side becomes white, the top side becomes a mottled darker variation of colors resembling the sea bottom, and their body flattens into an oval shape: thus the nickname “Flatfish”.

The fossil’s a great catch, but it’s unclear how it solves the “mystery.”

We know that the eyes migrate; they do so in every individual flatfish. The question of how an apparently complex developmental process is superintended over millions of years, with many accompanying adaptations required, and extinction the cost of failure – and how and why the process started – is still out there.

See the migration in developmental images:

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It is just a type and the fossil only shows a type. Its just a line of reasoning that there was a movement because its just about fossil sequence. Fossil sequence , even if accurate, is still not scientific evidence but only a line of reasoning about A-B. With another option the reasoning loses its power as persuasive. The other option here is just types of this creature were fossilized in a place of great diversity of its kind. Just like cichlids today. Or seals with different alignments in feet/leg structure. They are not from each other but living together at the same time. There is a logical flaw in evolutionism here where they place confidence in fossil sequences for info on origins. ID folk make the same error. EVEN if true its still just lines of reasoning. its not scientific evidence! General fossilization of diversity in a single event would also produce this SEQUENCE. Biology evidence or conclusions can;t be based on rocks. Robert Byers
We find irreducibly complex systems almost anywhere we look. This is certainly one of them! These types of systems are so incredibly complex and interrelated that I literally can't see how anyone in their right mind can think that they occurred through small gradual steps, each of which is more beneficial than the other - when it is obvious that there would be no benefit until the system is fully formed and functioning. All the "systems" of the body fall into this category I think, but especially the reproductive system seems an impossibility for evolution. Metamorphosis as well. tjguy

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