When we think of color vision, we imagine the variety of colors that the human eye can see. Perhaps people think that color vision is a huge advantage for animals, as opposed to dichromatic or even monochromatic vision. If that were the case, why don't all animals have color vision? One thought to keep in mind is what the purpose of seeing color is for animals. We'll delve deeper into how color vision can play a role in the lives of animals and humans. The different groups of animals we will look at are marine animals, neotropical wild apes, primates, and humans. The first area addressed will be that of animals with monochromatic vision. We need to know what it means to have monochromatic vision before we can understand why animals have this certain type of vision. Monochromatic vision occurs because a cone of vision is missing. Leo Peichl stated that many marine mammals lack the S cone opsin and only have an L cone opsin (1520). Many of these animals include the harbor seal, toothed whale, ringed seal, eared seal, earless seal, and bottlenose dolphin. The lack of ability to see more colors doesn't just apply to marine mammals. There are two primates that suffer from this color blindness, namely the owl monkey and the bushbaby (Peichl 1520). In water, color vision is not so important. Animals are able to use different senses and instincts to overcome their inefficiencies. Echolocation is a tool marine mammals have to help them find food so they don't have to use their vision. Peichl thinks that because there is a low amount of light during the night and marine mammals have adapted to still be able to see, this leads him to think "color vision m...... middle of the paper ......logy 32.5 (2011): 1058-1075. Academic Search Web. April 9, 2014. Fedigan, Linda M., et al. "is not supported by long-term fitness data from wild neotropical monkeys." Plos ONE 9.1 (2014): 1-10. Academic Search Premier. Web. April 9, 2014. Hall, Richard J. “The Evolution of Colorless Color Vision.” Philosophy of Science 63.3 (1996): S125. Academic Search Premier. Web. April 9, 2014. Jacobs, Gerald H. and Jeremy Nathans. “The evolution of color vision in primates.” » Scientific American 300.4 (2009): 56-63. 2014. Peichl, Leo, Günther Behrmann and Ronald HH Kröger. “For whales and seals, the ocean is not blue: a loss of visual pigment in marine mammals*. » European Journal Of Neuroscience 13.8 (2001): 1520-1528. Premier Academic Research. Internet. April 9. 2014.