Jester Jester A jester, court jester, or fool, was historically an entertainer during the medieval and Renaissance eras who was a member of the household of a nobleman or a monarch employed to entertain him and his guests. A jester was also an itinerant performer who entertained common folk at fairs and markets. Jesters are also modern-day entertainers who resemble their historical counterparts. Jesters in medieval times are often thought to have worn brightly coloured clothes and eccentric hats in a motley pattern and their modern counterparts usually mimic this costume. Jesters entertained with a wide variety of skills: principal among
Court jester hypothesis coined it. Westfall and Millar attribute the term to him (citing the 2001 paper) in a paper of their own from 2004. Michael Benton also credits Barnosky with coining the phrase. Since 2001, many researchers in evolution (such as Tracy Aze, Anthony Barnosky, Michael J. Benton, Douglas Erwin, Thomas Ezard, Sergey Gravilets, J.B.C. Jackson, Paul N. Pearson, Andy Purvis, Robert D. Westfall, and Constance I. Millar) have started to use the term "Court Jester hypothesis" to describe the view that evolution at a macro scale is driven by abiotic factors more than the biotic competition called the Red Queen hypothesis.