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According to Comparative Vertebrate Neuroanatomy, the XYW classfication is used for cat retina. They roughly correspond to the M, P, K cells in primates, respectively.


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Short answer In terms of visual function, the low-tier primary visual cortex and high-tier frontal cortex are inactivated. The activity of the intermediate ventral stream and limbic regions are increased, apparently uncoupling low- and high-level vision processing from the system. Background The sleep stage where visualizations (dreaming) occur is called ...


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Short answer The visible spectrum has the highest energy in sunlight at the earth's surface, explaining the gross location of the visible spectrum in life on earth. The specific frequency range varies across species and can be explained by species-specific survival strategies. Background When you look at the solar light spectrum at the earth's surface the ...


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Most of the light from the sun doesn't actually reach the earth's surface due to the atmosphere. [source] So the light reaching earth includes near-UV, visible, near-IR and a band of radio waves. Seeing any other part of the spectrum would be impossible since it doesn't reach earth. You asked why we only see in the visible light range; this is due to ...


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This is my speculation, but there are no or few organic chemicals which can absorb radio waves having longer wave lengths. Eyes sense lights by absorbing light with organic chemicals, but to sense longer wave length, eyes might need more sophisticated devices like tuners. In addition, less than 100nm radio waves from the outer space are absorbed by the ...


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"Visible light" is the wavelength of the light that we can see, if human beings could see UV or IR, those wavelengths had been included in the "visible light" definition. Now, our Sun is brightest in yellow-green light, which (you guess?) is right in the midle of the "visible light" spectrum. So the only remaining question is: "Why can we only see that short ...


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These wavelengths happen to satisfy two conditions. First, shorter wavelength photons (EM radiation) tend to be dangerous for biology. Even UV light (<350nm) is already can damage DNA. That is due to the fact that bond energies in biological molecules tend to have values close to energy of short-wavelength EM radiation. These is why high-energy particles ...


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Short answer Skewed X-inactivation may lead to phenotypic manifestation of X-linked color blindness. Background What an interesting question! In a study by Jorgensen et al. (1992) two female identical twins that were heterozygotes for X-linked deuteranomaly were investigated. Phenotypically, deuteranomaly refers to anomalous trichromacy, i.e., reduced ...


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Seeing in animals is at some level using Gabor wavelets (MarĨelja 1980 and later authors). Your images reminds of a combination of two low frequency Gabor basis vectors. Apparently the nervous system does not have time to model the incoming image into Gabor components of other frequencies. Here is a picture of two low frequency Gabor basis vectors added. ...



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