"Seeing Red" Questions


Mammal eye retinas have rod-shaped photoreceptors sensitive to any wavelength light. These rods allow black and white (gray scale) vision. Typically, mammals also have cone-shaped, color-sensing photoreceptors. Most mammals have dichromatic vision (having cones for blue and green light).

Read the article carefully then answer the questions in complete sentences on a separate sheet of paper.

  1. What could have happened many millions of years ago to cause one group of primates to start evolving into separate groups of New World and Old World primates?
  2. Describe how trichromatic vision is different from dichromatic vision.
  3. Traditionally, why did scientists think primates developed color vision?
  4. Why would monkeys prefer young, red leaves ?
  5. Howler monkeys started Gerald Jacobs thinking. Why?
  6. What are the names of the four Old World primates studied in Uganda?
  7. How do the diets of these trichromatic primates support Lucas' theory?
  8. What evidence from Neotropical primates does not support red color vision evolving for fruit eating?
  9. Describe how a simple genetic mutation might allow development of a trichromatic primate from dichromatic stock.
  10. The scientists mentioned in the article work at which three universities?
  11. List the three countries where the field studies took place and whether those areas are considered part of the New World or Old World.
  12. Compare and contrast placental and marsupial mammals.


Moffat, Anne Simon. "Seeing Red". Science. Jan 25, 2002. Vol 295. pp615.