Evolution of human colour vision similar. Tritanopes are missing the short wavelength sensitive opsins and see short wavelength colours in a green hue and dim compared to other colours. They may also see some short wavelength colours as black. Other perception problems include distinguishing yellow from pink or purple colours being perceived as shades of red. Researchers have found that trichromacy has advantages over dichromacy or anomalous trichromacy at further distances. This is believed to occur because visual cues such as shape decrease for colour vision as distance increases for targets of a smaller size. Using tests for spotting fruit pieces in bushes at distances
Evolution of human colour vision place in Ancestral Boreoeutherian species with the 7 mutations on genetically reconstructed Boreoetherian short wavelength sensitive opsins. λmax values were shifted from a value of 357 to 411, an increase which indicated that human short wavelength sensitive opsins did indeed evolve from Ancestral Boreoeutherian species using these 7 mutations. Further analysis has shown that 4008 out of the 5040 possible trajectories were terminated prematurely due to nonfunctional pigments that were dehydrated. Mutagenesis results also reveal that ancestral human short wavelength sensitive opsin remained UV-sensitive until about 80 million years ago before gradually increasing its λmax by 20 75 million years