The yellow colour of the lens of man and other primates

Abstract

SUMMARY1. Measurements have been made of the absorption spectra of the lenses of human, baboon (Papio), rhesus monkey (Macaca), squirrel monkey (Saimiri scurewr) and bush baby (Galago crassicaudatus).2. In all these species an absorption maximum was found between 365 and 368 nm.3. The pigment responsible for this absorption was water-soluble and aqueous extracts were examined. Protein-free aqueous extracts showed an additional maximum at 260 nm which could be only partially accounted for by the presence of ascorbic acid.4. Chromatography of the protein-free solution from human lenses yielded a fast-moving yellow component with a blue fluorescence. Its absorption spectrum was very similar to that of the original protein-free solution. A fast-moving yellow component from the baboon lens had a yellow fluorescence.5. The human lenses appeared to contain more of the yellow, watersoluble pigment at birth than in adult life. The concentration remains constant during adult life.6. There is evidence for the appearance of another pigment in the human lens in later adult life. It is not water-soluble and has an absorption maximum at about 330 nm.

Age and the transmittance of the human crystalline lens.

“…The problem of the different scales is considered below. While failing to note any variation in absorbance with age for wavelengths longer than 400 nm, Cooper & Robson (1969) reported both an increase in the absorbance in the UVA, and a systematic shift of the absorption maximum originally located at approximately 360 nm (cf. Fig.…”

The all-cone retina of the garter snake: spectral mechanisms and photopigment

“…Even in the highly pigmented lenses of primates and other diurnal mammals, there is little spectrally selective loss for wavelengths beyond about 500 nm (Cooper and Robson 1969;Yolton et al 1974). On the grounds that this would likely also be the case for the garter snake lens (even if it is somewhat pigmented), the spectral sensitivity functions obtained for high flicker rates were re-examined, this time only considering those wavelengths lying beyond 500 nm.…”

Spectral shifts of mammalian ultraviolet-sensitive pigments (short wavelength-sensitive opsin 1) are associated with eye length and photic niche evolution

“…Indeed, some diurnal mammal lenses transmit little to no UV light [30,31], but the lenses of certain nocturnal [18,30,31] and subterranean [4,20] mammals transmit UV light effectively, suggesting that photic niche (i.e. overall amount of light encountered by a species) may be influencing lens transmittance and ultimately SWS1 spectral tuning.…”