“The crowding effect in tapeworm infections,” an article by Clark P. Read, appeared in the Journal of Parasitology (37: 174–178) in April 1951. It has been one of the most widely and frequently cited papers over the last 50 yr. When I began thinking about the “Defining the Field” series for the Journal, the “crowding effect” paper was an obvious choice.
On a personal note, I can vividly recall spending time with Read’s paper as a graduate student in the late 1950s and early 1960s. After all, even by that time it was a must read (no pun intended!), and I am certain that I have read or at least perused it more than one time since. While re-reading the paper just a few months ago, I became quite intrigued (as one with an ecological interest) by what I thought it had said when I first read it many...