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Eric J, Warrant
D
D
B
L
D
D
Fig. lOA-F. Eye structure and depth in hyperiid amphipods. Amphipods from different depths
are shown at left: A Thamneus sp. (surface), C Parapronoe crustulum (200m), and E Phronima
sedentaria ( < 800 m). At right (B, D and F), their respective vertical distributions of anatomical
resolution (cycles deg· 1 ) are shown (here calculated as I/2Lif/>). Note how resolution in the
surface species is low and rather uniform throughout the visual field (B). In deeper species the
eye becomes more bilobed, with the dorsal lobe (viewing the downwelling light) dominating.
Resolution in the dorsal lobe increases with depth (D and F) and becomes more dorsally
directed. D dorsal; L lateral. (After Land 1989b)
Eric J, Warrant
D
D
B
L
D
D
Fig. lOA-F. Eye structure and depth in hyperiid amphipods. Amphipods from different depths
are shown at left: A Thamneus sp. (surface), C Parapronoe crustulum (200m), and E Phronima
sedentaria ( < 800 m). At right (B, D and F), their respective vertical distributions of anatomical
resolution (cycles deg· 1 ) are shown (here calculated as I/2Lif/>). Note how resolution in the
surface species is low and rather uniform throughout the visual field (B). In deeper species the
eye becomes more bilobed, with the dorsal lobe (viewing the downwelling light) dominating.
Resolution in the dorsal lobe increases with depth (D and F) and becomes more dorsally
directed. D dorsal; L lateral. (After Land 1989b)