Dan E Nilsson

..In contrast, the compound eyes in myriapods and chelicerates are likely to date back to ancestors with corneal lenses and probably without the ability to discriminate colour and polarization...

..Recent work on the expression of retinal transcription factors and other molecular cues delivers interesting but partly contradictory information on the early phases of eye evolution...

..Recent work on gene expression in specified cell types, together with comparative studies of developmental genes in cnidarians, now show some promise to a solution of the controversy...

..Photoreceptor cells of vertebrate eyes are fundamentally different from those of invertebrate eyes. New work on the brain of a ragworm now suggests that ancestral bilaterians possessed both types of photoreceptor cell...

..We argue that this may be useful in eyes serving a single visual task. The findings indicate that tailoring of complex receptive fields might have been one of the original driving forces in the evolution of animal lenses...

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..Unlike the upper lens-eye lens of T.cystophora, the same eye in C.bronzie did not display any significant optical power...

..They also hold a lens-like structure, but its optical power is minute. Optical modeling suggests spatial resolution, but only in one plane. These unique and intriguing traits support strong peripheral filtering...

..The data collected in this study support the idea that the visual system of box jellyfish is a collection of special purpose eyes...

..Here we expand this knowledge by demonstrating the presence of molecularly preserved melanin in intimate association with melanosome-like microbodies isolated from an argentinoid fish eye from the early Eocene of Denmark...