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(a) Individuals were reared for up to 132 days, at which age they show an adult visual phenotype, under either blue or red light conditions [4]. At two time points (118 and 132 dph), proportional cone opsin expression analyses revealed cone opsin expression differences between the light treatments but also between time points. (b) Proportional Quantum Catch (QC) of cone opsins in the two light treatments. (c) At 118 dph, a subset of individuals was exchanged between the light treatments. Expression of single cone opsins changed rapidly in response to novel light condition, whereas double cone opsin expression was not affected, as measured by qPCR. (d) Ambient light can affect rates of ontogenetic progression in opsin expression and could even be reverted to a previous ontogenetic state (modified from [16]).

(a) Individuals were reared for up to 132 days, at which age they show an adult visual phenotype, under either blue or red light conditions [4]. At two time points (118 and 132 dph), proportional cone opsin expression analyses revealed cone opsin expression differences between the light treatments but also between time points. (b) Proportional Quantum Catch (QC) of cone opsins in the two light treatments. (c) At 118 dph, a subset of individuals was exchanged between the light treatments. Expression of single cone opsins changed rapidly in response to novel light condition, whereas double cone opsin expression was not affected, as measured by qPCR. (d) Ambient light can affect rates of ontogenetic progression in opsin expression and could even be reverted to a previous ontogenetic state (modified from [16]).

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... Additionally, a recent study showed that opsin coexpression might be a novel mechanism for modulating color vision [22]. However, it is unclear whether the direction and extent of opsin expression plasticity is limited by ontogeny [23]. ...
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... This could be the case if ontogenetic changes occur gradually across the retina. Although such information is not available, plastic changes in opsin expression do appear to follow a dorsoventral pattern, with changes occurring earlier in the ventral versus the dorsal retina (Härer et al., 2019). Nevertheless, the observation that this phenotype is associated with clear water environments (in at least four of the five species, see above) also suggests a functional role. ...
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