The Color-Sensitive Cones. In 1965 came experimental confirmation of a long expected result - there are three types of color-sensitive cones in the retina of the human eye, corresponding roughly to red, green, and blue sensitive detectors.
Most PGA Tour caddies make between $1000 and $1500 per week, but they also make a percentage of what the player wins in the tournaments. This usually equates to 5 percent of any finish outside the top 10. Players breaking into the top 10, but not winning, will share 7 percent of their prize with their caddies.
US PGA Championship 2015: Caddies for Rory McIlroy and Jordan Spieth could earn up to $180,000 in prize money. I'm a sports and sports business journalist with City A.M. Follow me for coverage of the industry behind sports and the money made by top athletes.