- Amphistium
"Amphistium" is a genus of fossil fish which has been identified as an early relative of the
Flatfish , and as aTransitional fossil . In a typical modern flatfish, the head is asymmetric with both eyes on one side of the head. In "Amphistium", the transition from the typical symmetric head of a vertebrate is incomplete, with one eye placed near the top of the head. [Matt Friedman, "The evolutionary origin of flatfish assymetry", "Nature" volume 454 number 7201 (10 July 2008) pages 209-212 doi: 10.1038/nature07108]"Heteronectes" is similar fossil.
References
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