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  3. Hydrothermal vents along the mid-ocean ridges host ephemeral ecosystems of diverse fauna, including several crustacean spec

Hydrothermal vents along the mid-ocean ridges host ephemeral ecosystems of diverse fauna, including several crustacean spec

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问题          Hydrothermal vents along the mid-ocean ridges host ephemeral ecosystems
     of diverse fauna, including several crustacean species, some of which undergo
     development as larvae up to 1,000 meters above and 100 kilometers away from
     the vents. For example, vent crab Bythograea thermydron (at stage of
(5)   larvae) possess image-forming compound eyes with a visual pigment sensitive to
     the blue light of upper oceanic waters. As these larvae metamorphose into
     adulthood and begin to descend to and settle at the vents, they lose their image-
     forming optics and develop high-sensitivity naked-retina eyes. With maturation,
     the spectral absorbance of the visual pigment in these eyes also shifts towards
(10)  longer wavelengths and this progressive visual metamorphosis trades imaging
     for increased sensitivity, and changes spectral sensitivity to the dim, longer
     wavelengths of light existing at the bottom of the ocean. As hydrothermal vents
     produce light, vision may supplement thermal and chemical senses to orient
     post-larval settlement at vent sites.
选项 A、Adaptive Visual Metamorphosis in Deep-Sea Vent Crabs
B、Aspects of the General Anatomical Development of Deep-Sea Vent Crabs
C、New Research Directions in the Study of Deep-Sea Vent Crabs
D、Common Features of Optics of Lower Depth Oceanic Animals
E、Patterns of Anatomical Transformation in Lower Oceanic Creatures
答案A
解析
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